WO2002079903A9 - Measurement, and utilization of network latency in protocols - Google Patents
Measurement, and utilization of network latency in protocolsInfo
- Publication number
- WO2002079903A9 WO2002079903A9 PCT/US2001/050418 US0150418W WO02079903A9 WO 2002079903 A9 WO2002079903 A9 WO 2002079903A9 US 0150418 W US0150418 W US 0150418W WO 02079903 A9 WO02079903 A9 WO 02079903A9
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- network
- time
- monitoring
- server
- web
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/06—Generation of reports
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/12—Discovery or management of network topologies
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/08—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
- H04L43/0852—Delays
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/08—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
- H04L43/0852—Delays
- H04L43/0864—Round trip delays
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/50—Network service management, e.g. ensuring proper service fulfilment according to agreements
- H04L41/5003—Managing SLA; Interaction between SLA and QoS
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/50—Network service management, e.g. ensuring proper service fulfilment according to agreements
- H04L41/5003—Managing SLA; Interaction between SLA and QoS
- H04L41/5009—Determining service level performance parameters or violations of service level contracts, e.g. violations of agreed response time or mean time between failures [MTBF]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/50—Network service management, e.g. ensuring proper service fulfilment according to agreements
- H04L41/5061—Network service management, e.g. ensuring proper service fulfilment according to agreements characterised by the interaction between service providers and their network customers, e.g. customer relationship management
- H04L41/507—Filtering out customers affected by service problems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/08—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
- H04L43/0823—Errors, e.g. transmission errors
- H04L43/0829—Packet loss
Definitions
- the invention relates to data communications monitoring and analysis, and more particularly to techniques for analyzing the performance of network servers and WAN networks.
- the invention relates to techniques for measuring network latency using transaction-based protocols such as HTTP.
- the World Wide Web has emerged as an important if not essential part of modern everyday life for many individuals and business throughout the world. We can now use the World Wide Web to obtain information, perform transactions such as shopping and procurement, exchange information with one another, and for a wide variety of other uses and applications.
- response latency i.e., time delay between when a client makes a request and the time the client receives the requested information
- response latency can depend on a number of complex factors only some of which may relate to server performance and others of which relate to general network latency, it may be desirable to analyze the different factors involved in the latency of a particular request to determine the principle causes.
- a business model centering around offering third party server performance monitoring services would have a distinct advantage if the performance monitoring to be done remotely (e.g., over the Internet) without the need to disturb or otherwise modify the server being monitored and which could measure and report on actually prevailing network conditions. In other situations, local monitoring is desirable but more accurate monitoring of additional parameters would be highly desirable.
- the present invention offers a solution to this problem by providing a monitoring capability for transaction-based protocols based on round-trip network latency time.
- One aspect of remote monitor subscription-based service provided by the invention employs a network of monitors on Internet backbones around the world to simulate visits to any Web site and to report performance results.
- the service allows Web managers to test the performance ("health") of their Web sites from a visitor's perspective by monitoring the availability and response times for URLs, customer transactions, external content providers and more.
- the new service goes beyond simple monitoring of a Web site. It allows Web managers to quickly detect, respond to and prevent Web site performance problems related to Internet congestion, ISP service level, external content provider performance, overall Web site design and internal Web site component failure.
- Such a remote monitor service package may use independent servers strategically placed around the world to determine how a Web site is performing and to simulate a visitor's experience at any given moment.
- this service allows Web managers to react to problems before their customers experience any dissatisfaction, yet creates only a negligible (or no) load on their Web infrastructure. Because it is a hosted service, Web managers can sign up and begin monitoring their site almost immediately without installation or maintenance headaches.
- Web managers can keep a vigilant watch on critical site performance metrics such as the time it takes to serve Web pages and the success of visitors' transactions on the site, for example form submissions* searches and purchases. They can also monitor their service level agreements with external services, such as credit card approval, advertising or news. Using such remote monitoring capability, Web managers can compare their site's availability to their competitors' and check performance from key servers around the world to determine where geographic bottlenecks may be occurring.
- An example network monitoring system provided by a preferred embodiment of the invention detects, responds to and prevents performance problems. For example, a monitor may be used to deliver actionable information to help Web managers detect, respond to and prevent Web site performance problems. Using such a monitor, Web managers set acceptable thresholds for the performance of desired Web site activities.
- a "trigger level" for performance is exceeded, a message alert is sent to their pager, cell phone or e-mail. For example, a message could be sent when a Web page takes more than 6 seconds to load or a transaction fails to complete. This quick response makes it possible to take corrective action before a situation turns critical.
- Web managers can respond quickly.
- the alerts from the remote monitor can include information to help pinpoint the source of the problem.
- Web managers can also log on to their account from any Web browser to troubleshoot a problem using a web-enabled console and easily drill down to the detail level of the problem, as well as review extensive online reports.
- Network monitor can provide numerous reports, which allow the Web manager to analyze whether performance problems are occurring outside the firewall, and if so, devise solutions. Those might include, e.g., working with an ISP to achieve better backbone peering or setting up distributed caching solutions.
- Subscription Packages and Pricing Subscription packages for remote monitor can be designed to be flexible so that Web managers can monitor one URL or monitor their entire e-business.
- Service packages can include monitoring site availability, response time and/or transactions with data gathered from a single remote location or multiple locations worldwide.
- a basic subscription might, for example, measure availability and response time for five URLs from one location every 30 minutes.
- a more comprehensive subscription package could include a number of monitors measuring transaction performance from various monitoring locations throughout the world as often as every five minutes.
- An aspect provided by the invention separates the initial web server reply from all subsequent HTTP replies to a given client's HTTP transaction request.
- TCP network transport
- TCP gathered network transport
- One way to monitor such parameters is to connect a network adapter card onto the network the server and client are operating upon and placing the network adapter card into promiscuous mode.
- a network adapter card operating in promiscuous mode can be used to monitor transaction-based protocol traffic remotely and break down response time into various components.
- Transaction-based protocols generally employ a client that sends out requests, working with a server that services those requests by providing a reply that can span one or more data packets. There can be many requests between the client and the server over the life of a particular session. When we monitor these requests, we are able to get detailed information about how time is spent on the network while the transaction completes.
- round-trip network latency calculations can be applied to transaction-based protocols such as HTTP. Determining the amount of network latency is beneficial because this time, although calculated as part of the total transaction time, does not represent time spent on the client or the server. When analyzing web server response time or performance, this round- trip latency can be determined and utilized.
- Knowing the round-trip network latency value is beneficial to web masters and network administrators. For example, if web response time is slow, and the round-trip network latency value is high, addressing slow responsiveness requires that the problem be addressed on the network ⁇ not on the web server. Conversely, if the round-trip network latency value is low, slow response is best addressed by looking at web server performance.
- Additional features and advantages provided in accordance with aspects of a remote monitor system and method provided by the present invention include: • Detailed reports showing IT managers how factors such as customer location, ISP connectivity, backbone peering issues, network infrastructure and other variables are affecting site performance
- Remote Monitor uses a unique in-depth process to tell why a site is not responding. For example, Remote Monitor can verify that page content is correct, retrieval time is acceptable, and back-end databases are responding properly.
- Remote Monitor doesn't flood a server operator with data from dozens of servers around the world — it isolates issues and provides specific information showing exactly what is affecting user performance:
- Monitor availability This includes URL availability, file checking, IP throughput and HTTP response time. You'll know at all times whether a URL is available or not, and you'll find out about downtime before your customers do.
- Monitor page load time Your site may be up, but if a page or data takes too long to load, your site might as well be down. With Remote Monitor, you get alerts immediately whenever thresholds are crossed.
- Remote Monitor can send alerts to a pager, cell phone or e-mail as soon as your defined response time thresholds are crossed.
- Monitor connectivity With Remote Monitor in place, you can accurately assess which parts of your network are affecting user performance. You can focus on the parts of your network that are critical to performance, instead of investing time and money where it's not really needed. For example, if users in Dallas experience slow response times, you may need to implement an additional data center in Texas rather than adding additional bandwidth to your data center on the West Coast.
- Monitor applications With Remote Monitor in place, you can accurately assess which parts of your infrastructure are affecting end user experience. By monitoring certain applications and seeing results over time, you can determine which applications may be affecting performance.
- Monitor third parties Track the performance of services you are paying for — such as services from third party vendors, including web hosting, ad servers, load-balancing solutions, content servers, and cache server vendors.
- a monitor allows measurement for the availability and response time of a URL, Ping, DNS request, FTP transfer, or URL sequence (transaction)
- a subscription-based service that uses a global network of servers to monitor web site performance from outside the firewall, from a user perspective.
- Remote monitoring agents are strategically distributed on major backbone segments around the world to simulate the end- user's experience of your web site at any given moment. Without independent monitors located away from your infrastructure, there is no way to accurately assess how your e-business is performing.
- Performance Reports are stored online (e.g., with 45 days data) for easy viewing and provide the knowledge you need to prevent problems from recurring.
- Remote monitor can tell you how your content and application partners are performing.
- Remote Monitor has the ability to detect the presence of certain strings of content, such as "file not found", or specific URLs to ensure that that content partners are performing as agreed. In the event of a content or application partner failure, customers are able to immediately identify the source of a problem.
- Remote monitor tell you how your cache server vendors are performing.
- Remote Monitor monitors cache servers by setting up a URL monitor for the cached content (e.g., HTTP://www.yoursite.akamai.com). In this manner, remote monitor can report on your cache servers performance in each geographic location.
- Remote Monitor's infrastructure is based on secure VPN technology.
- Remote Monitor can be tailored to your needs by purchasing one or more packages that focus on availability, response times, global monitoring and transaction monitoring.
- the architecture of Remote Monitor is based on a central server, database, data collection agents, and web console. Users access this data via a browser connected to the central server. This location also hosts the database and serves as the data collection point.
- the data collection agents are themselves strategically placed around the globe in major metropolitan locations with top backbone providers. All configuration and reporting data are available from the web browser interface.
- Remote Monitor is designed to be extremely easy to configure and use. Its focus is monitoring the critical performance parameters (availability, responsiveness, and throughput) of web front-end components. With Remote Monitor, the web operation administrator can immediately:
- Remote Monitor can be provided as a service, so the customer does not have to install or manage any software or hardware components. Access to reports, current status, and user configuration can be through a web browser interface accessible from any platform over the Internet.
- Alert options allow the web operations administrator full control of when to be notified of site performance problems.
- Alert options include the ability to specify a response threshold for unacceptable performance as well as options to ensure that content is accurately delivered. Additionally, notifications can be configured so that they are sent only when performance/availability problems occur on more than one data collection agent. This minimizes false alerts that may occur due to regional/vendor network issues when most end users can still access the web site.
- alert notifications When alert notifications are sent, they include the relevant details about the problems currently occurring, including a traceroute to pinpoint network problems if Remote Monitor is unable to reach the site. This allows web operators to quickly identify and fix the problem based on their pager messages.
- Remote Monitor was designed to collect detailed performance reporting and help provide feedback for better site design. Reports highlight where time is spent when retrieving a web page or performing a transaction (such as purchasing a book). With Remote Monitor's intuitive drill-down reporting, users can quickly assess if the site contains too many large images, or if the problem is poor network connectivity. This allows the web team to immediately focus on areas that will improve site performance and enhance end users' experiences.
- Remote Monitor measures time spent retrieving partner content separately from the time spent retrieving onsite content. Reports that highlight partner time allow the web team to quickly pinpoint performance issues related to third- party content. Remote Monitor can help manage third-party content providers like ad servers and ensure that SLAs are being met.
- monitoring the web components in your data center can be supplemented with monitoring site performance from a user's perspective. Inside the firewall, one can monitor the critical data center components that comprise your Web systems.
- Remote Monitor uses a global network of global servers to monitor your site's performance outside the firewall, from the end- user's perspective.
- the combination can provide an integrated solution for monitoring and managing the web site.
- the user will have a single console to use for configuring all monitoring activities on the web system, a single place to configure and generate alerts, and an integrated data repository for all management data and reports.
- Console provides a real-time view into the status of one or more monitored web system components. This lets you "drill down” into any current problems for further information on the recent history surrounding the situation.
- Holistix provides other real-time benefits through action plans that can be programmed to send an alert (for example, a pager alert or an SNMP trap) under a variety of conditions, correct the problem automatically, or some combination of these or other remedial steps.
- an alert for example, a pager alert or an SNMP trap
- Remote Monitor can identify which component is contributing to the problem.
- Remote Monitor can monitor both the supplier and consumer sides of distributed content publishing and correlate the management data in a central database. Either side can then use the Console to understand or troubleshoot problems in the total content delivery system. Remote Monitor can export performance, status, and availability data so that business partners or consumers can render this information within their own management and reporting tools.
- Figure 2 is a block diagram of an example monitor system
- Figure 3 shows example network transactions
- Figure 4 illustrates the various latencies within an example network transaction
- Figure 5 shows an example detailed web page request time breakdown
- Figure 6 shows an example round-trip network latency calculation
- Figure 7 is a flowchart of example steps performed by the Figure 2 network monitor;
- Figure 8 shows an example connect time metric bucket breakdown;
- Figure 9 shows an example network monitor architecture
- Figures 10A-10C show example web page-based reports.
- Figure 1 shows an example overall network monitor system S provided by an example preferred embodiment of this invention.
- System S monitors the performance of a server 14 with one or a plurality of network monitors 16 via a network 12.
- Network 12 may comprise, for example, the global Internet or
- network monitors 16 are located remotely from server 14, and are coupled to server 14 via the same network 12 that clients (not shown) of server 14 use to communicate with the server.
- An advantage of locating the network monitors 16 remotely from server 14 is that the network monitors in
- the network device(s) 16 report monitoring results to a centralized database 20 for reporting purposes.
- Database 20 can be used to alert the operator of server 14 to performance degradation conditions through 5 various means such as, for example, initiating a page or cell phone call to the operator's portable or stationary alerting device 18a, and providing reports 18b in hardcopy or via electronic means (e.g., e-mail, via a reporting web site, or the like).
- TCP/IP Protocol/Internet Protocol
- IETF RFC 791 and 793
- the invention is not limited to HTTP and TCP/IP, but can be used with any transaction-based network communications protocol. Such protocols of the type currently in wide spread use on the Internet are described here for purposes of illustration only.
- one or more network monitors 16 are coupled to network 12.
- Network monitors 16 are used to monitor network communications between server 14 and client 10.
- network monitors 16 are located remotely from both server(s) 14 and client 10.
- network monitors could be located at the site of a network monitoring service that offers network monitoring on a subscription or other basis to the operator of server 14 and any number of additional servers 14.
- network monitor 16 is coupled to the subnetwork 13 that server(s) 14 are coupled to so as to facilitate monitoring of traffic between the server(s) 14 and client(s) 10.
- one or more network monitors 16 could be placed locally with server 14 and/or client 10.
- network monitor 16 could be equipped with sophisticated traffic monitoring functionality (e.g., such as that possessed by national security agencies) to allow it to monitor traffic on the Internet 12.
- network monitors 16 are located in a distributed fashion at various nodes or other geographical presence points of network 12. For example, if server 14 serves clients 10 located worldwide, network monitors 16 can be distributed throughout the world. For example, a network monitor 16a could be located in California, another network monitor 16b could be located in New York, a further network monitor 16c could be located in London, yet another network monitor 16d could be located in Tokyo, etc. Such a distributed system of network monitors 16 provide a capability to monitor actual network conditions prevailing throughout network 12, and can be used to measure the speed and other performance of server 14 throughout network 12. While a plurality of network monitors 16 distributed network 12 provides certain advantages, the invention is not limited to a plurality of monitors but can be used with only a single network monitor.
- network monitor(s) 16 can operate passively by monitoring the data communications traffic between server 14 and client 10. For example, a network monitor 16 can listen to network 12 (subnetwork 13) to detect requests for web pages or other information from a client 10 to server 14, and may monitor the response provided by the server to the client. Using such monitoring techniques, network monitor 16 can determine speed performance and other parameters associated with server 14 and/or network 12. Network monitor 16 can be co-located with server 14 so as to obtain geographic network latencies, packet loss, etc. Network monitor 16 can monitor requests from a number of different clients 10 located at different points within network 12 so as to measure performance degradation resulting from network congestion or other network-related factors as opposed to performance degradation resulting from the performance of server 14. In this way, system S can determine whether slowdowns are the result of problems within server 14, problems within network 12, or both.
- network monitor(s) 16 can themselves initiate requests to server 14 and receive responses from the server ⁇ or other software on the same or different computer that supports the network monitor(s) 16 can impersonate a web browser to initiate such requests.
- network monitor(s) 16 act as clients in this active mode, they add to the loading of server 14 which may be undesirable under heavy loading conditions.
- network monitor(s) 16 do not initiate too many requests, such active mode can be used to supplement (or in some cases as a substitute for) passive monitoring of data communications traffic between client 10 and server 14.
- network monitor(s) 16 could trigger real-time events based upon percent packet loss or other determinations.
- a server 14 operator can subscribe to the network monitoring services by completing a web-based form, and by providing a URL, IP address or other network address or other locator to the network monitor(s) 16, and providing some form of payment (e.g., credit card, billing address or the like).
- Network monitor(s) 16 can begin monitoring the performance of remotely located server 14 substantially immediately, and provide reporting also via network 12 to report and display 18. In this way, a new business can be supported that uses the existing network 12 infrastructure and one or a number of network monitors 16 to monitor the performance of any number of servers 14 communicating over network 12 with any number of clients 10.
- While remote location of network monitor(s) 16 provides certain advantages as described above, it also creates certain challenges. In particular, it is a challenge to provide useful performance diagnostic information based only on observation of traffic flowing over network 12. More specifically, it may be important in offering such network monitoring services to diagnose whether performance degradations are due to problems at or within server 14, problems existing within network 12, or both.
- the example embodiment solves this problem by calculating network round-trip latency based on communications flowing back and forth between client 10 and server 14. In other words, by monitoring certain parameters (described in detail below) in connection with the transaction-based protocols used by server 14 to communicate with client 10, network monitor(s) 16 of the example embodiment can deduce which portions of overall network delays are due to latency existing within server 14 and which part of the overall delay is due to transport over the network 12. Such deduced information is very useful in helping the operator of server 14 to isolate problems of slow response when, for example, a web browser user requests a web page from server 14 and has to wait a long time to receive the page.
- one or more additional object fetches e.g., inline graphics or the like
- each initiated by the client 10's browser parsing the web page delivered in phase B and transmitting an additional request for a particular object to server 14 (phases Cl-CN)
- latency (a synonym for delay) is an expression of how much time it takes for a packet of data to get from one designated point to another.
- network latency is measured when a packet is sent and a reply or acknowledgment packet comes back to the sender. This round-trip time is considered the network latency.
- the contributors to network latency include:
- Propagation This is simply the time it takes for a packet to travel between one place and another at the speed of light.
- Transmission The medium itself (whether fiber optic cable, wireless, or some other) introduces some delay.
- the size of the packet introduces delay in a round trip since a larger packet will take longer to receive and return that a short one.
- Each gateway node takes time to examine and possibly change packet headers
- Network monitor 16 can get the network transport time (Tn), web processing time, web client processing time (Tc), retransmit time, dropped packets, and network latency when it is co-located with the server 14 or when it is remotely located.
- Tn network transport time
- Tc web client processing time
- retransmit time time
- dropped packets packets
- network latency network latency
- a remote monitoring device can send a request to server 14 and receive a response, or it can monitor a request sent by another client 10 and log both the time at which the client sends the request and the time at which the client receives the response.
- the remote monitor can determine ⁇ T S + ⁇ T n .
- the present invention solves this problem by carefully monitoring different aspects of various transactions and deriving a measure of round-trip network latency. This round-trip latency parameter can be subtracted from the total latency to derive a measure of web server processing time ⁇ T S and the total network latency ⁇ T n .
- a transaction-based protocol such as HTTP for example, uses a network transport protocol (e.g., TCP) to establish a session (e.g., a connection) between a web client and the web server.
- TCP network transport protocol
- the time spent for this connection to complete may be termed TCP connect time (see Figure 5, block 50).
- This time calculation generally includes network latency and other possible network-induced delays that could occur.
- the remaining time, once these other factors are discounted, is the TCP connect processing time ( Figure 5, block 54) spent on the server (a type of web server processing time ⁇ Ts related to establishing a TCP connection).
- the web client After the TCP connection is established, the web client typically sends an HTTP request to server 14 and receives the associated HTTP reply that comes back from the server 14. We call this the initial web server response time (Figure 5, block 56). From this point until the point when all of the packets in the HTTP reply are sent back to the client 10 may be called the Remaining HTTP Content Time ( Figure 5, block 62). Dividing the HTTP transaction into these distinct parts lays the foundation for breaking down the overall response time.
- the initial web server response time includes, for example, web page setup, web page generation, and content server access time in a web-server based context.
- network monitor 16 continuously calculates the minimum round-trip network latency as shown in Figure 6. As shown in Figure 6, various characteristics/features of the transport protocol can be used to determine minimum network latency from which round-trip network latency can be derived:
- TCP network transport
- TCP network transport
- remote monitor 16 it is also possible using the remote monitor 16 provided by the example embodiment of this invention to, under some circumstances, determine the amount of time a client spends processing requests from server 14. For example, sometimes a client 10 can't process transmissions from a server 14 fast enough and the network transport (TCP) on the client 10 employs flow control to slow down the server 14. Network monitor 16 can determine this and provide measurements and reports that, take this effect into account.
- TCP network transport
- the remaining HTTP content time is logically separated from the initial web server response time because negligible web server application processing time is spent during this period.
- the web server does all the required processing necessary to generate all web page data to be sent to the client. This time includes web page setup, web page generation, and content server access. All web page content is then passed down to the network transport (TCP) protocol.
- TCP network transport
- any web server application processing time is negligible and is therefore attributable to the network transport protocol.
- Web page content delivery delays are attributable to the following conditions:
- FIG. 7 shows an example flowchart used to perform a network monitoring operation in accordance with an example preferred embodiment of this invention.
- a monitoring device 16 including, for example, a network adapter card programmed to operate in the so-called promiscuous mode is used to monitor the TCP and HTTP (or other transaction- based) protocol exchanges between the client 10 and a server 14 (or the same techniques could be used for monitoring peer-to-peer communications).
- monitoring device 16 first calculates the TCP connect time (block 102) by, for example, calculating the time from when the SYN packet is sent by client 10 to server 14 until the time the server replies with a SYN ACK (acknowledgment) packet. If the monitoring device 16 is co- located with server 14, then this measurement directly indicates how quickly server 14 can initiate an TCP session. When this same measurement is taken with monitoring device 16 being located remotely from server 14, the time calculation will also include network latency, other possible network-induced delays that could occur, and TCP connect processing time spent on the web server.
- the TCP connection does not actually complete until the final acknowledgment (ACK) is sent by the client to the server 14. It is possible to separate an initial TCP connect time from a final TCP connect time to include this last acknowledgment if necessary (particularly if monitoring is co-located with the web server).
- network monitor 16 also begins continually tracking round-trip network latency, packet loss and retransmission timing (block 103). Such tracking can begin at the same time as block 102 begins to monitor, and can continue through the actual TCP disconnect (which completes in block 111). Calculate Initial Server Response Time
- Measuring device 16 also calculates an initial server response time parameter (block 104).
- This initial server response time is the amount of time used for an HTTP Get or Post request from client 10 until server 14 replies with an HTTP OK (or some other HTTP response). If monitoring device 16 is co-located with server 14, then this calculation represents how quickly the web server can turn around a client request.
- Such a response time measurement when taken locally at the server 14, reflects all of the actual web server application processing time for the request.
- Server 14 gathers all of the information to be sent to client 10 before the initial reply to the client. This information gathering time includes, for example, web page setup, web page generation and accessing any necessary content servers. Once all of the data is ready to be sent to client 10, it is all handed to the network transport layer (TCP) on server 14 to then be transmitted to client 10.
- TCP network transport layer
- the time calculation will also include network latency, other possible network induced delays that could occur, and of course, the web server processing time itself.
- the distinction is blurred between the actual web server processing time, network latency, and other network-induced factors.
- HTTP requests sent from the client 10 to the server 14 can be for static or dynamic web content. It is useful to be able to distinguish between the two.
- Replies to dynamic content requests usually include requests for information from a back-end database, and this can take a significant amount of time if the database query or the connection to the database is slow.
- An initial reply is often delayed when dynamic content is requested by the client 10 and is reflected in the delayed response time to the client. Since static content generation time is quicker, it makes sense to create at least two separate initial server response time categories ⁇ one for static and one for dynamic content pages.
- the step of block 104 can examine the HTTP header reply. If the reply indicates that there is a "content length" with a number of bytes immediately following, then this is handled as a static page.
- server 14 uses HTTP 1.0 reply instead of an HTTP 1.1 reply, it can be presumed that the content of the page is static since HTTP 1.0 does not support dynamic content. All other content that does not meet these conditions can be assumed to be dynamic.
- the network monitor 16 can determine whether all data has been delivered from the server (decision block 110) using various techniques. One technique is to detect whether the client 10 has issued another HTTP Get or Post request. The issuance of the second client 10 request indicates that the previous request is complete. This assumes, that over a given TCP session, there cannot be more than one request outstanding at a time. Another technique that network monitor 16 can use to determine server 14 has completely satisfied the request of client 10 is to monitor whether the TCP connection is closed by either client 10 or server 14 (see Figure 3, phase D).
- the ⁇ (time delay) between HTTP reply packet and the last sent packet with user data from the server 14 to the client 10 can be used to determine remaining HTTP content time. For example, once all HTTP reply data for an individual Get or Post request has been received, block 110 may wait for either the next Get or Post request OR a TCP disconnect sequence. If the next Get or Post request occurs, then we go back to block 104 and calculate the next 'Initial Server Response Time'. If a TCP disconnect sequence begins, we continue to monitor the TCP disconnect until it completes in block 111, then we derive the final calculations for min network latency, web server processing time, client time, network transport time, etc. in block 112.
- the network transport time as described above is the time from the initial web server HTTP reply packet until all content is delivered to the web client 10.
- the network transport time from server 14 to client 10 also initially includes HTTP client processing time spent by client 10. Any HTTP client processing time that occurred during this time needs to be subtracted.
- any transport retransmission time of the client Get or Post request sent to server 14 needs to be included as network transport time.
- this time is discounted as web server processing time since the server 14 presumably did not receive the request.
- the time taken during the retransmit instead gets included as network transport time.
- the resulting values can be reported (block 114).
- the remaining HTTP content time calculation includes network latency as well as possible network-induced delays that could occur during the transmission of the data, regardless of whether the network monitor 16 is local or remote from server 14 (see Figure 6).
- This remaining HTTP content time parameter includes, in addition to client processing time, the following:
- the remaining HTTP content time is categorized as network transport time.
- the server 14 application delivers all client web page data to the network transport, the remaining HTTP content time starts as soon as the first packet is sent to client 10. All time spent delivering the remaining HTTP content is attributed to the network transport factors listed above ⁇ not the application running on server 14.
- network monitor 16 derives estimated network latency (see Figure 6) by continuously computing round-trip times for data that is sent and acknowledged by the remote peer.
- Network monitor 16 can, for example, time stamp both TCP data packet and TCP bit flag (SYN or FIN) packet requests when they are sent to the remote peer.
- Network monitor 16 can then compute how long it takes for the packet to be acknowledged by the remote peer and then derive an estimated network latency time for one round trip. There can be multiple round trips for a TCP session. The value of the minimum network latency time for the duration of the TCP session is continuously kept to determine the final minimum network latency time once the TCP session is terminated (block 111).
- Another calculation that can provide a snapshot of the network latency time is the examination of TCP slow start algorithms employed by web server for congestion avoidance. The value obtained will be used in the same manner as described in the retransmission time calculation above. If this value is less than any previous network latency time, then this value may be used instead.
- a network latency time measurement can be obtained when the web server 14's TCP stack employs the slow start algorithm. This is calculated for the first HTTP Get or Post request for a TCP session sent to the web server for which the web server sends at least three data packets in response to this HTTP request.
- a time stamp is made of the acknowledgment (ACK) sent to server 14 for the second data packet sent from the server in its initial HTTP reply (provided packet 1 or 2 from the server is the TCP negotiated MSS size).
- a slow start algorithm on the server prevents packet 3 from being sent until packet 2 is acknowledged by client 10.
- Second, a time stamp is made of the third data packet sent from the web server that can be sent once the client 10 sends an ACK of packet 2. The ⁇ between these two time stamps is a very accurate network latency time calculation.
- the HTTP total time is the time from the Get or Post request from client 10 until all of the data is sent from the server 14 to the client 10. This time calculation will include network latency as well as possible network induced delays. These delays should occur during transmission of the data regardless of whether the network monitor 16 is local to or remote from server 14. Alternatively, this same HTTP total time can also be determined by adding together the network transport time, web server processing time and web client processing time parameters.
- Web server processing time is the amount of time spent responding to the Get or Post request from the client 10.
- the web server processing time can be determined easily when measured on the same network as server 14 because no network-induced delays need to be accounted for (network-induced delays would rarely occur in this instance).
- the initial server response time parameter described above accurately measures the web server response time.
- TCP flow control prevents server 14 from sending any more data until client 10 is ready.
- the TCP protocol header window size advertised by the client 10 to the server 14 is zero (the client 10 has room for zero more bytes of data).
- client 10 actually the web client application, not to be confused with the TCP stack on client 10, in the example embodiment
- the TCP flow control mechanism increases the window size advertised to server 14.
- Such client processing time may, thus feature, in one example:
- the ⁇ T between the first TCP zero byte window packet in the TCP window update by the client 10 and the (following this) first non-zero byte TCP window update by the client 10 is the HTTP client processing time that can be subtracted to obtain a another measure of network latency.
- HTTP client processing time when HTTP client processing time is measured at the locale of server 14, the actual client may not necessarily be the end user's desk top machine.
- proxy servers on their behalf (e.g., AOL), and in this situation, it may be a proxy server advertising a zero byte window rather than the actual client desk top machine.
- packet loss i.e., the number of times it is believed that TCP packets have been dropped from the sending side of an HTTP session (either the client 10 or the server 14).
- a dropped packet typically means a packet was sent out initially and the packet originator had to re-send the packet.
- packets being lost (dropped) between server 14 and client 10 may be more likely to occur (at least in the context of a web server) since a greater abundance of data is sent from the web server to the client.
- Block 103 considers a packet to be lost if the sequence number in the TCP header sent out is less than or equal to any previous sequence number that was sent.
- the sender could be re-transmitting previously transmitted data, but more information is required.
- On the Internet for example, it is very normal that packets arrive out of order because of the nature of IP layer routing. If network monitor 16 is not co-located with server 14, additional checks using the IP Header Sequence IDs and inter-packet timing information can be used to differentiate between TCP packets that arrive out of order because of Internet routing issues and TCP packets that are truly lost or dropped.
- the initial HTTP Get or Post client 10 request requires an immediate server 14 reply.
- This data packet reply can be retransmitted even though it does not arrive, necessarily, as out-of-order data. It is possible to determine that this is a retransmit condition by looking carefully at the HTTP reply from the server 14. If the reply arrives after a TCP delayed ACK (acknowledge) timer that server 14 would have fired to generate a naked delayed ACK (to the initial HTTP Get or Post packet) with no accompanying data and if no naked delayed ACK came from the server 14 it can be deduced that this is a TCP retransmitted packet.
- TCP delayed ACK acknowledgenowledge
- the "to web server” and “to web client” retransmission times for those packet losses can be calculated (block 103) independently.
- the retransmission time is calculated from the point the original packet was sent out by the web server 14 until the retransmitted packet actually left the server.
- the retransmission time is calculated by using the older of the following two time stamps:
- the ⁇ T (time differential) between this time stamp and the retransmitted frame time stamp is the retransmission time.
- the device sending the retransmitted data may do so in a manner that is not conducive to the efficient use of the network. For example, sometimes the sender fears its data got lost and tries to retransmit the packet data to the client too quickly.
- Duplicate (or gratuitous) data is a packet that is sent for no good reason because the remote peer has already sent an acknowledgment for this retransmitted data.
- network monitor 16 is located remotely from server 14, notifying a network administrator when this situation becomes severe (i.e., lots of duplicate data sent from the web server) can be very useful. It may be that the web server 14 has a retransmit timer that is too aggressive and it needs to be tuned.
- too much duplicate data being sent from the client 10 may mean that the TCP delayed acknowledgment timer set too passively and needs to be a bit more aggressive.
- HTTP data size Another parameter of interest is HTTP data size or average size. This parameter is the total amount of HTTP payload data that is sent from the server 14 to the client 10 that resulted from an HTTP Get or Post request. Both the HTTP send and HTTP receive data totals are kept, but the only one that is of use is the HTTP receive data. Average page size calculations could be made using this value as well.
- the average hop count calculation could be used for comparative purposes.
- average hop count could be used to contrast the apparent network distance between various measuring locations and the server 14 that is being monitored.
- the average hop count is calculated by looking at every IP packet that comes from server 14 to obtain the "time to live” (TTL) field in the IP header.
- TTL time to live
- the average TTL value is calculated once the TCP session closes, and can be used for comparison purposes to other sites accessing the same web server 14.
- the average TTL value received by the network monitor 16 does not reflect the actual number of hops from the web server 14 to the web client 10.
- TCP/IP stacks start the TTL field (which is decremented by one with each hop on the Internet) with different values depending upon how the server 14's TCP stack is configured.
- this calculation can be used for comparison purposes only when connecting to the same web server 14 site.
- we can inject TCP packets destined to server 14 (using web server port number) using a mechanism much like traceroute.
- the benefit of this approach is that the ICMP time-exceeded datagrams should come back to client 10 for the TCP packets sent to server 14.
- the generated ICMP echo request packets to server 14 are discarded for security reasons by many web sites and networks.
- Report information gathered by the network monitor 16 for various metrics can be placed into specific "buckets" for use by another platform or application (block 114).
- Each of these "buckets” can be divided into groupings of time or quantity. Groups will represent a range of acceptable to unacceptable metric values. For example, if a metric is collecting the amount of time taken to make an HTTP connection from a web client 10 to a web server 14, one might create a "bucket” with the breakdown of possible connect times as shown in Figure 8. In the Figure 8 example, one might consider all except the last "bucket" of four seconds or higher to be perfectly acceptable connect times for the client 10. However, if the percentage of four seconds or higher started to represent ten percent of the users, then this might be problematic.
- network monitor 16 may calculate in remote and co-located modes:
- DNS time An additional parameter (DNS time) could be used to calculate the time form when an initial DNS request goes out until the reply comes back. This calculation could be implemented by network monitor 16 if desired by simply decoding DNS requests and monitoring the time between a request and an associated response.
- FIG. 9 shows an example architecture for a network monitor 16 provided in the example embodiment.
- a promiscuous mode adapter/card receiver 16a is coupled to network 12 to be monitored.
- Promiscuous mode adapter/card receiver receives transaction-based protocol requests and responses comprising the data traffic flowing back and forth through network 12 between client 10 and server 14.
- protocol analyzer 16b which analyzes the various characteristics of the received protocol information in accordance with the features discussed above.
- a real time clock 16c coupled to receiver 16a and/or protocol analyzer 16b allows a real time stamp to be associated with each piece of protocol being analyzed by protocol analyzer 16b.
- Analyzer 16b logs the time at which receiver 16a receives various pieces of protocol having the characteristics described above.
- This logged information may be stored on a data logger 16d.
- protocol analyzer 16b determines that a particular transaction or series of transactions has completed, it requests a latency calculator 16e to access the information logged by data logger 16d and calculate, in response thereto, the various latencies described above. These calculated latencies are provided to a reporting arrangement 16e for reporting, e.g., over network 12 to a centralized data facility 20 and/or to other reporting destinations.
- Terry is dealing with increasingly complex Web systems that are susceptible to performance degradation. They include an array of critical components behind his firewall and many variables outside it that he can't necessarily control. As he sits inside his Chicago data center without a remote monitoring solution in place, Terry lacks the answers to several critical questions. For instance:
- a remote monitor provided in accordance with the present invention could show Terry how his site is performing from an end-user's point of view — and help him determine what's affecting user experience. That's because such a remote monitor can use a global server network to monitor his site's availability, response times and transactions from beyond his data center. Without such a remote monitor, Terry doesn't know how people are experiencing his Web site from an office across the street, much less in London.
- a status screen shows him that although the average response time for his home page is under the 6 second threshold he set for it, response time from London is dragging — critically. Calm and collected, Terry clicks for location details and sees (see Figure 10B) that according to his London monitor, his home page is moving quite slowly.
- the remote monitor display can display availability and response time for Terry's home page from multiple remote monitoring locations. Availability is fine across the board.
Abstract
Description
Claims
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU2001297721A AU2001297721A1 (en) | 2000-12-21 | 2001-12-20 | Measurement, and utilization of network latency in protocols |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/740,804 | 2000-12-21 | ||
US09/740,804 US7937470B2 (en) | 2000-12-21 | 2000-12-21 | Methods of determining communications protocol latency |
Publications (3)
Publication Number | Publication Date |
---|---|
WO2002079903A2 WO2002079903A2 (en) | 2002-10-10 |
WO2002079903A3 WO2002079903A3 (en) | 2003-01-09 |
WO2002079903A9 true WO2002079903A9 (en) | 2004-05-13 |
Family
ID=24978149
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2001/050418 WO2002079903A2 (en) | 2000-12-21 | 2001-12-20 | Measurement, and utilization of network latency in protocols |
Country Status (3)
Country | Link |
---|---|
US (1) | US7937470B2 (en) |
AU (1) | AU2001297721A1 (en) |
WO (1) | WO2002079903A2 (en) |
Families Citing this family (245)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6108637A (en) | 1996-09-03 | 2000-08-22 | Nielsen Media Research, Inc. | Content display monitor |
US6993591B1 (en) * | 1998-09-30 | 2006-01-31 | Lucent Technologies Inc. | Method and apparatus for prefetching internet resources based on estimated round trip time |
US7281040B1 (en) * | 2000-03-07 | 2007-10-09 | Cisco Technology, Inc. | Diagnostic/remote monitoring by email |
US8392552B2 (en) | 2000-09-28 | 2013-03-05 | Vig Acquisitions Ltd., L.L.C. | System and method for providing configurable security monitoring utilizing an integrated information system |
AU2001296925A1 (en) | 2000-09-28 | 2002-04-08 | Vigilos, Inc. | Method and process for configuring a premises for monitoring |
CA2422519A1 (en) * | 2000-09-28 | 2002-04-04 | Vigilos, Inc. | System and method for dynamic interaction with remote devices |
US7627665B2 (en) * | 2000-09-28 | 2009-12-01 | Barker Geoffrey T | System and method for providing configurable security monitoring utilizing an integrated information system |
US7577701B1 (en) * | 2001-01-22 | 2009-08-18 | Insightete Corporation | System and method for continuous monitoring and measurement of performance of computers on network |
US7082465B1 (en) * | 2001-03-27 | 2006-07-25 | Cisco Technology, Inc. | Web based management of host computers in an open protocol network |
US7792948B2 (en) * | 2001-03-30 | 2010-09-07 | Bmc Software, Inc. | Method and system for collecting, aggregating and viewing performance data on a site-wide basis |
US7461369B2 (en) * | 2001-03-30 | 2008-12-02 | Bmc Software, Inc. | Java application response time analyzer |
US7506047B2 (en) * | 2001-03-30 | 2009-03-17 | Bmc Software, Inc. | Synthetic transaction monitor with replay capability |
US7197559B2 (en) * | 2001-05-09 | 2007-03-27 | Mercury Interactive Corporation | Transaction breakdown feature to facilitate analysis of end user performance of a server system |
US7827257B2 (en) * | 2001-06-19 | 2010-11-02 | Intel Corporation | System and method for automatic and adaptive use of active network performance measurement techniques to find the fastest source |
US20030023716A1 (en) * | 2001-07-25 | 2003-01-30 | Loyd Aaron Joel | Method and device for monitoring the performance of a network |
US7117521B2 (en) * | 2001-08-31 | 2006-10-03 | Intel Corporation | Method to measure the perceived quality of streaming media |
US7437450B1 (en) * | 2001-11-30 | 2008-10-14 | Cisco Technology Inc. | End-to-end performance tool and method for monitoring electronic-commerce transactions |
US7106757B2 (en) * | 2001-12-19 | 2006-09-12 | Intel Corporation | System and method for streaming multimedia over packet networks |
US7480715B1 (en) | 2002-01-25 | 2009-01-20 | Vig Acquisitions Ltd., L.L.C. | System and method for performing a predictive threat assessment based on risk factors |
US20030167335A1 (en) * | 2002-03-04 | 2003-09-04 | Vigilos, Inc. | System and method for network-based communication |
US20030206172A1 (en) * | 2002-03-05 | 2003-11-06 | Vigilos, Inc. | System and method for the asynchronous collection and management of video data |
JP4267462B2 (en) | 2002-04-08 | 2009-05-27 | インターナショナル・ビジネス・マシーンズ・コーポレーション | Method and system for problem determination in distributed enterprise applications |
US20030221000A1 (en) * | 2002-05-16 | 2003-11-27 | Ludmila Cherkasova | System and method for measuring web service performance using captured network packets |
US8392499B2 (en) * | 2002-05-16 | 2013-03-05 | Hewlett-Packard Development Company, L.P. | System and method for relating aborted client accesses of data to quality of service provided by a server in a client-server network |
WO2004001555A2 (en) | 2002-06-25 | 2003-12-31 | International Business Machines Corporation | Method and system for monitoring performance of application in a distributed environment |
US7286527B2 (en) * | 2002-07-26 | 2007-10-23 | Brocade Communications Systems, Inc. | Method and apparatus for round trip delay measurement in a bi-directional, point-to-point, serial data channel |
WO2004012126A2 (en) * | 2002-07-29 | 2004-02-05 | Opinionlab, Inc. | System and method for providing substantially real-time access to collected information concerning user interaction with a web page of a website |
US7478121B1 (en) | 2002-07-31 | 2009-01-13 | Opinionlab, Inc. | Receiving and reporting page-specific user feedback concerning one or more particular web pages of a website |
US7370285B1 (en) * | 2002-07-31 | 2008-05-06 | Opinionlab, Inc. | Receiving and reporting page-specific user feedback concerning one or more particular web pages of a website |
US7167912B1 (en) * | 2002-08-09 | 2007-01-23 | Cisco Technology, Inc. | Method and apparatus for detecting failures in network components |
EP1536597B1 (en) * | 2002-09-06 | 2015-01-21 | Fujitsu Limited | Radio network control apparatus |
US20040111510A1 (en) * | 2002-12-06 | 2004-06-10 | Shahid Shoaib | Method of dynamically switching message logging schemes to improve system performance |
JP3801559B2 (en) | 2002-12-26 | 2006-07-26 | ソニー株式会社 | COMMUNICATION DEVICE AND METHOD, RECORDING MEDIUM, AND PROGRAM |
US7454494B1 (en) * | 2003-01-07 | 2008-11-18 | Exfo Service Assurance Inc. | Apparatus and method for actively analyzing a data packet delivery path |
US20040156370A1 (en) * | 2003-02-07 | 2004-08-12 | Lockheed Martin Corporation | System for evolutionary adaptation |
US7292723B2 (en) * | 2003-02-26 | 2007-11-06 | Walker Digital, Llc | System for image analysis in a network that is structured with multiple layers and differentially weighted neurons |
US7543051B2 (en) * | 2003-05-30 | 2009-06-02 | Borland Software Corporation | Method of non-intrusive analysis of secure and non-secure web application traffic in real-time |
US7827487B1 (en) | 2003-06-16 | 2010-11-02 | Opinionlab, Inc. | Soliciting user feedback regarding one or more web pages of a website without obscuring visual content |
WO2005017715A2 (en) * | 2003-08-15 | 2005-02-24 | International Business Machines Corporation | Method and system for monitoring performance of processes across multiple environments and servers |
US7640359B1 (en) * | 2003-09-19 | 2009-12-29 | At&T Intellectual Property, I, L.P. | Method, system and computer program product for facilitating the design and assignment of ethernet VLANs |
US20050066036A1 (en) * | 2003-09-19 | 2005-03-24 | Neil Gilmartin | Methods, systems and computer program products for facilitating the design and analysis of virtual networks based on total hub value |
US7624187B1 (en) | 2003-09-19 | 2009-11-24 | At&T Intellectual Property, I, L.P. | Method, system and computer program product for providing Ethernet VLAN capacity requirement estimation |
US8949380B2 (en) * | 2003-09-29 | 2015-02-03 | Eqapez Foundation, L.L.C. | Method and system for distributing images to client systems |
US8291061B2 (en) * | 2003-10-08 | 2012-10-16 | Hewlett-Packard Development Company, L.P. | Method and system for business-oriented web services management |
US7349985B2 (en) * | 2003-11-24 | 2008-03-25 | At&T Delaware Intellectual Property, Inc. | Method, system and computer program product for calculating a VLAN latency measure |
US20060004697A1 (en) * | 2004-06-09 | 2006-01-05 | Lipsky Scott E | Method and system for restricting the display of images |
US20060013231A1 (en) * | 2004-06-22 | 2006-01-19 | Sbc Knowledge Ventures, Lp | Consolidated ethernet optical network and apparatus |
US20060029016A1 (en) * | 2004-06-29 | 2006-02-09 | Radware Limited | Debugging application performance over a network |
GB2417391B (en) | 2004-08-18 | 2007-04-18 | Wecomm Ltd | Transmitting data over a network |
US9621473B2 (en) | 2004-08-18 | 2017-04-11 | Open Text Sa Ulc | Method and system for sending data |
JP3931988B2 (en) * | 2004-08-26 | 2007-06-20 | 日本電気株式会社 | Network quality measuring method and measuring apparatus |
US7958208B2 (en) * | 2004-09-22 | 2011-06-07 | At&T Intellectual Property I, L.P. | System and method for designing a customized switched metro Ethernet data network |
US8738759B2 (en) * | 2004-09-23 | 2014-05-27 | Hewlett-Packard Development Company, L.P. | System and method for service response monitoring |
EP1679835A1 (en) * | 2005-01-07 | 2006-07-12 | Koninklijke KPN N.V. | Method, device and system for predicting a data session time |
KR20060084040A (en) * | 2005-01-17 | 2006-07-21 | 삼성전자주식회사 | Apparatus and method for dynamic qos management |
US7826376B1 (en) * | 2005-01-25 | 2010-11-02 | Symantec Operating Corporation | Detection of network problems in a computing system |
JP2006279466A (en) * | 2005-03-29 | 2006-10-12 | Fujitsu Ltd | System, program, and method for monitoring |
US7685270B1 (en) * | 2005-03-31 | 2010-03-23 | Amazon Technologies, Inc. | Method and apparatus for measuring latency in web services |
US8284679B1 (en) * | 2005-04-22 | 2012-10-09 | At&T Intellectual Property Ii, L.P. | Method and apparatus for detecting service disruptions in a packet network |
US20060259348A1 (en) * | 2005-05-10 | 2006-11-16 | Youbet.Com, Inc. | System and Methods of Calculating Growth of Subscribers and Income From Subscribers |
EP1739557A1 (en) * | 2005-06-30 | 2007-01-03 | Nortel Networks Limited | Method for analyzing browsing and device for implementing the method |
CN1925431A (en) * | 2005-08-31 | 2007-03-07 | 华为技术有限公司 | Method for file host-host protocol service significance testing |
US20070140306A1 (en) * | 2005-12-16 | 2007-06-21 | International Business Machines Corporation | Identifying existence and rate of jitter during real-time audio and video streaming |
JP2007201564A (en) * | 2006-01-23 | 2007-08-09 | Nec Corp | Estimate system, terminal, estimate method, and program |
JP2007221207A (en) * | 2006-02-14 | 2007-08-30 | Hitachi Ltd | Managing apparatus and communication system |
US8892737B2 (en) * | 2006-03-06 | 2014-11-18 | Vmware, Inc. | Network sniffer for performing service level management |
US7693996B2 (en) * | 2006-03-06 | 2010-04-06 | Vmware, Inc. | Service level management system |
US7519734B1 (en) * | 2006-03-14 | 2009-04-14 | Amazon Technologies, Inc. | System and method for routing service requests |
US20070299965A1 (en) * | 2006-06-22 | 2007-12-27 | Jason Nieh | Management of client perceived page view response time |
US8717911B2 (en) | 2006-06-30 | 2014-05-06 | Centurylink Intellectual Property Llc | System and method for collecting network performance information |
US8477614B2 (en) | 2006-06-30 | 2013-07-02 | Centurylink Intellectual Property Llc | System and method for routing calls if potential call paths are impaired or congested |
US8289965B2 (en) | 2006-10-19 | 2012-10-16 | Embarq Holdings Company, Llc | System and method for establishing a communications session with an end-user based on the state of a network connection |
US8488447B2 (en) | 2006-06-30 | 2013-07-16 | Centurylink Intellectual Property Llc | System and method for adjusting code speed in a transmission path during call set-up due to reduced transmission performance |
US8194643B2 (en) | 2006-10-19 | 2012-06-05 | Embarq Holdings Company, Llc | System and method for monitoring the connection of an end-user to a remote network |
US9094257B2 (en) | 2006-06-30 | 2015-07-28 | Centurylink Intellectual Property Llc | System and method for selecting a content delivery network |
US8775237B2 (en) | 2006-08-02 | 2014-07-08 | Opinionlab, Inc. | System and method for measuring and reporting user reactions to advertisements on a web page |
US8130793B2 (en) | 2006-08-22 | 2012-03-06 | Embarq Holdings Company, Llc | System and method for enabling reciprocal billing for different types of communications over a packet network |
US8531954B2 (en) | 2006-08-22 | 2013-09-10 | Centurylink Intellectual Property Llc | System and method for handling reservation requests with a connection admission control engine |
US7843831B2 (en) | 2006-08-22 | 2010-11-30 | Embarq Holdings Company Llc | System and method for routing data on a packet network |
US7684332B2 (en) | 2006-08-22 | 2010-03-23 | Embarq Holdings Company, Llc | System and method for adjusting the window size of a TCP packet through network elements |
US8064391B2 (en) | 2006-08-22 | 2011-11-22 | Embarq Holdings Company, Llc | System and method for monitoring and optimizing network performance to a wireless device |
US8274905B2 (en) | 2006-08-22 | 2012-09-25 | Embarq Holdings Company, Llc | System and method for displaying a graph representative of network performance over a time period |
US8238253B2 (en) | 2006-08-22 | 2012-08-07 | Embarq Holdings Company, Llc | System and method for monitoring interlayer devices and optimizing network performance |
US8144587B2 (en) | 2006-08-22 | 2012-03-27 | Embarq Holdings Company, Llc | System and method for load balancing network resources using a connection admission control engine |
US8199653B2 (en) | 2006-08-22 | 2012-06-12 | Embarq Holdings Company, Llc | System and method for communicating network performance information over a packet network |
US8223655B2 (en) * | 2006-08-22 | 2012-07-17 | Embarq Holdings Company, Llc | System and method for provisioning resources of a packet network based on collected network performance information |
US8307065B2 (en) | 2006-08-22 | 2012-11-06 | Centurylink Intellectual Property Llc | System and method for remotely controlling network operators |
US8619600B2 (en) | 2006-08-22 | 2013-12-31 | Centurylink Intellectual Property Llc | System and method for establishing calls over a call path having best path metrics |
US8407765B2 (en) | 2006-08-22 | 2013-03-26 | Centurylink Intellectual Property Llc | System and method for restricting access to network performance information tables |
US8224255B2 (en) | 2006-08-22 | 2012-07-17 | Embarq Holdings Company, Llc | System and method for managing radio frequency windows |
US8537695B2 (en) | 2006-08-22 | 2013-09-17 | Centurylink Intellectual Property Llc | System and method for establishing a call being received by a trunk on a packet network |
US8576722B2 (en) | 2006-08-22 | 2013-11-05 | Centurylink Intellectual Property Llc | System and method for modifying connectivity fault management packets |
US8189468B2 (en) | 2006-10-25 | 2012-05-29 | Embarq Holdings, Company, LLC | System and method for regulating messages between networks |
US9479341B2 (en) | 2006-08-22 | 2016-10-25 | Centurylink Intellectual Property Llc | System and method for initiating diagnostics on a packet network node |
EP1895459A1 (en) * | 2006-08-31 | 2008-03-05 | Opinionlab, Inc. | Computer-implemented system and method for measuring and reporting business intelligence based on comments collected from web page users using software associated with accessed web pages |
US7716321B2 (en) * | 2006-11-01 | 2010-05-11 | Sony Corporation | Method and system for providing recommendations for internet content providers |
US8255873B2 (en) * | 2006-11-20 | 2012-08-28 | Microsoft Corporation | Handling external content in web applications |
US7779133B2 (en) * | 2007-01-04 | 2010-08-17 | Yahoo! Inc. | Estimation of web client response time |
US8214483B2 (en) * | 2007-02-28 | 2012-07-03 | Red Hat, Inc. | Method and system for continuous availability subscription service |
US8578337B2 (en) * | 2007-02-28 | 2013-11-05 | Red Hat, Inc. | Method and system for quality assurance subscription service |
US7694189B2 (en) * | 2007-02-28 | 2010-04-06 | Red Hat, Inc. | Method and system for remote monitoring subscription service |
US9946982B2 (en) * | 2007-02-28 | 2018-04-17 | Red Hat, Inc. | Web-based support subscriptions |
US9135075B2 (en) * | 2007-03-09 | 2015-09-15 | Hewlett-Packard Development Company, L.P. | Capacity planning for computing systems hosting multi-tier application based on think time value and resource cost of composite transaction using statistical regression analysis |
US7779127B2 (en) * | 2007-03-09 | 2010-08-17 | Hewlett-Packard Development Company, L.P. | System and method for determining a subset of transactions of a computing system for use in determing resource costs |
US8159961B1 (en) | 2007-03-30 | 2012-04-17 | Amazon Technologies, Inc. | Load balancing utilizing adaptive thresholding |
US7921410B1 (en) * | 2007-04-09 | 2011-04-05 | Hewlett-Packard Development Company, L.P. | Analyzing and application or service latency |
CA2689479A1 (en) * | 2007-06-04 | 2008-12-11 | Bce Inc. | Methods and systems for validating online transactions using location information |
US9306812B2 (en) * | 2007-07-05 | 2016-04-05 | Rpx Clearinghouse Llc | System and method for providing network application performance management in a network |
US8949405B2 (en) * | 2007-08-08 | 2015-02-03 | Google Inc. | Content server latency determination |
US8429544B2 (en) * | 2007-08-08 | 2013-04-23 | Google Inc. | Content server latency demonstration |
JP5039479B2 (en) * | 2007-08-20 | 2012-10-03 | キヤノン株式会社 | Data communication apparatus, control method thereof, and program |
US8392529B2 (en) | 2007-08-27 | 2013-03-05 | Pme Ip Australia Pty Ltd | Fast file server methods and systems |
US8271836B2 (en) * | 2007-09-27 | 2012-09-18 | Microsoft Corporation | Capturing diagnostics in web browser applications |
US7917446B2 (en) * | 2007-10-31 | 2011-03-29 | American Express Travel Related Services Company, Inc. | Latency locator |
US8326970B2 (en) * | 2007-11-05 | 2012-12-04 | Hewlett-Packard Development Company, L.P. | System and method for modeling a session-based system with a transaction-based analytic model |
US9904969B1 (en) | 2007-11-23 | 2018-02-27 | PME IP Pty Ltd | Multi-user multi-GPU render server apparatus and methods |
US8319781B2 (en) | 2007-11-23 | 2012-11-27 | Pme Ip Australia Pty Ltd | Multi-user multi-GPU render server apparatus and methods |
US8548215B2 (en) | 2007-11-23 | 2013-10-01 | Pme Ip Australia Pty Ltd | Automatic image segmentation of a volume by comparing and correlating slice histograms with an anatomic atlas of average histograms |
US10311541B2 (en) | 2007-11-23 | 2019-06-04 | PME IP Pty Ltd | Multi-user multi-GPU render server apparatus and methods |
US9019287B2 (en) | 2007-11-23 | 2015-04-28 | Pme Ip Australia Pty Ltd | Client-server visualization system with hybrid data processing |
US8326971B2 (en) * | 2007-11-30 | 2012-12-04 | International Business Machines Corporation | Method for using dynamically scheduled synthetic transactions to monitor performance and availability of E-business systems |
JP5056438B2 (en) * | 2008-01-29 | 2012-10-24 | 富士通株式会社 | Packet analysis method |
US7958190B2 (en) * | 2008-03-07 | 2011-06-07 | Fluke Corporation | Method and apparatus of end-user response time determination for both TCP and non-TCP protocols |
US7865455B2 (en) * | 2008-03-13 | 2011-01-04 | Opinionlab, Inc. | System and method for providing intelligent support |
US8340477B2 (en) * | 2008-03-31 | 2012-12-25 | Intel Corporation | Device with automatic image capture |
US20090245114A1 (en) * | 2008-04-01 | 2009-10-01 | Jayanth Vijayaraghavan | Methods for collecting and analyzing network performance data |
US8068425B2 (en) | 2008-04-09 | 2011-11-29 | Embarq Holdings Company, Llc | System and method for using network performance information to determine improved measures of path states |
US8589541B2 (en) | 2009-01-28 | 2013-11-19 | Headwater Partners I Llc | Device-assisted services for protecting network capacity |
US8832777B2 (en) | 2009-03-02 | 2014-09-09 | Headwater Partners I Llc | Adapting network policies based on device service processor configuration |
US7860973B2 (en) * | 2008-06-27 | 2010-12-28 | Microsoft Corporation | Data center scheduler |
US7925785B2 (en) * | 2008-06-27 | 2011-04-12 | Microsoft Corporation | On-demand capacity management |
US20090327460A1 (en) * | 2008-06-27 | 2009-12-31 | Microsoft Corporation | Application Request Routing and Load Balancing |
EP3068107B1 (en) * | 2008-09-05 | 2021-02-24 | Pulse Secure, LLC | Supplying data files to requesting stations |
US8224976B2 (en) * | 2008-12-24 | 2012-07-17 | Juniper Networks, Inc. | Using a server's capability profile to establish a connection |
US9980146B2 (en) | 2009-01-28 | 2018-05-22 | Headwater Research Llc | Communications device with secure data path processing agents |
US9565707B2 (en) | 2009-01-28 | 2017-02-07 | Headwater Partners I Llc | Wireless end-user device with wireless data attribution to multiple personas |
US10237757B2 (en) | 2009-01-28 | 2019-03-19 | Headwater Research Llc | System and method for wireless network offloading |
US9706061B2 (en) | 2009-01-28 | 2017-07-11 | Headwater Partners I Llc | Service design center for device assisted services |
US9572019B2 (en) | 2009-01-28 | 2017-02-14 | Headwater Partners LLC | Service selection set published to device agent with on-device service selection |
US10798252B2 (en) * | 2009-01-28 | 2020-10-06 | Headwater Research Llc | System and method for providing user notifications |
US9009296B1 (en) | 2009-08-07 | 2015-04-14 | Google Inc. | System and method of determining latency |
EP2288080B1 (en) * | 2009-08-18 | 2012-01-18 | ABB Technology AG | Analysing a communication performance of an IED |
US8886746B2 (en) * | 2009-09-09 | 2014-11-11 | Rockwell Automation Technologies, Inc. | Diagnostic module for distributed industrial network including industrial control devices |
US8584123B2 (en) * | 2009-10-08 | 2013-11-12 | International Business Machines Corporation | Linking transactions |
US8316126B2 (en) | 2009-10-08 | 2012-11-20 | International Business Machines Corporation | Stitching transactions |
US9117013B2 (en) | 2009-10-08 | 2015-08-25 | International Business Machines Corporation | Combining monitoring techniques |
US10157117B2 (en) * | 2009-10-08 | 2018-12-18 | International Business Machines Corporation | Processing transaction timestamps |
US8817653B2 (en) * | 2009-10-30 | 2014-08-26 | At&T Intellectual Property I, L.P. | Detecting irregular retransmissions |
EP2497034A4 (en) | 2009-11-04 | 2013-07-31 | Cedexis Inc | Internet infrastructure survey |
US8332232B2 (en) * | 2009-11-05 | 2012-12-11 | Opinionlab, Inc. | System and method for mobile interaction |
CA2927532C (en) * | 2009-12-10 | 2016-08-09 | Royal Bank Of Canada | Synchronized processing of data by networked computing resources |
WO2011123643A2 (en) | 2010-04-01 | 2011-10-06 | Enphase Energy, Inc. | Method and apparatus for managing installation information |
US8407340B2 (en) * | 2010-04-09 | 2013-03-26 | Microsoft Corporation | Page load performance analysis |
US10447767B2 (en) * | 2010-04-26 | 2019-10-15 | Pure Storage, Inc. | Resolving a performance issue within a dispersed storage network |
US9021362B2 (en) * | 2010-07-19 | 2015-04-28 | Soasta, Inc. | Real-time analytics of web performance using actual user measurements |
US8499065B2 (en) * | 2010-09-30 | 2013-07-30 | The Nielsen Company (Us), Llc | Methods and apparatus to distinguish between parent and child webpage accesses and/or browser tabs in focus |
US8589558B2 (en) * | 2010-11-29 | 2013-11-19 | Radware, Ltd. | Method and system for efficient deployment of web applications in a multi-datacenter system |
US8543868B2 (en) * | 2010-12-21 | 2013-09-24 | Guest Tek Interactive Entertainment Ltd. | Distributed computing system that monitors client device request time and server servicing time in order to detect performance problems and automatically issue alerts |
US8886795B2 (en) * | 2011-01-27 | 2014-11-11 | Hewlett-Packard Development Company, L.P. | Method and system for determining response time of a server |
US9524351B2 (en) * | 2011-03-10 | 2016-12-20 | Microsoft Technology Licensing, Llc | Requesting, responding and parsing |
US9077627B2 (en) | 2011-03-28 | 2015-07-07 | Hewlett-Packard Development Company, L.P. | Reducing impact of resource downtime |
US20120263058A1 (en) * | 2011-04-15 | 2012-10-18 | Jds Uniphase Corporation | Testing shaped tcp traffic |
US20120278459A1 (en) * | 2011-04-26 | 2012-11-01 | Cisco Technology, Inc. | Throttling bursty cpu utilization due to bursty tcp flows |
US8782162B1 (en) * | 2011-07-20 | 2014-07-15 | Google Inc. | System for merging and comparing real-time analytics data with conventional analytics data |
US8782166B1 (en) * | 2011-07-20 | 2014-07-15 | Google Inc. | System for generating a site pathing report based on real-time analytics data |
US8489679B2 (en) * | 2011-08-16 | 2013-07-16 | Fluke Corporation | Method and apparatus for monitoring network traffic and determining the timing associated with an application |
US8972569B1 (en) * | 2011-08-23 | 2015-03-03 | John J. D'Esposito | Remote and real-time network and HTTP monitoring with real-time predictive end user satisfaction indicator |
US8745245B1 (en) * | 2011-09-15 | 2014-06-03 | Google Inc. | System and method for offline detection |
US9386127B2 (en) | 2011-09-28 | 2016-07-05 | Open Text S.A. | System and method for data transfer, including protocols for use in data transfer |
US8937864B2 (en) * | 2011-12-06 | 2015-01-20 | Cisco Technology, Inc. | Channel quality aware transport flow compensation |
TWI539296B (en) * | 2011-12-12 | 2016-06-21 | 和沛科技股份有限公司 | Method for triggering computing process for migration location of virtual machines and application program for the same |
US8996661B1 (en) * | 2012-02-09 | 2015-03-31 | Instart Logic, Inc. | Smart packaging for mobile applications |
DE102012101881B4 (en) * | 2012-03-06 | 2013-11-21 | Softing Ag | Method for determining the topology of a serial asynchronous data bus |
US9167021B2 (en) | 2012-03-30 | 2015-10-20 | Citrix Systems, Inc. | Measuring web browsing quality of experience in real-time at an intermediate network node |
WO2013149207A1 (en) | 2012-03-30 | 2013-10-03 | Bytemobile , Inc. | Measuring web browsing quality of experience in real-time at an intermediate network node |
CN103379041B (en) * | 2012-04-28 | 2018-04-20 | 国际商业机器公司 | A kind of system detecting method and device and flow control methods and equipment |
US9729414B1 (en) | 2012-05-21 | 2017-08-08 | Thousandeyes, Inc. | Monitoring service availability using distributed BGP routing feeds |
US10230603B2 (en) | 2012-05-21 | 2019-03-12 | Thousandeyes, Inc. | Cross-layer troubleshooting of application delivery |
US9183564B2 (en) * | 2012-06-29 | 2015-11-10 | Yahoo! Inc. | Framework for marketplace analysis |
US8972509B2 (en) * | 2012-07-27 | 2015-03-03 | Adobe Systems Incorporated | Automated rich-content messaging |
US9893971B1 (en) * | 2012-12-31 | 2018-02-13 | Juniper Networks, Inc. | Variable timeouts for network device management queries |
US9509802B1 (en) | 2013-03-15 | 2016-11-29 | PME IP Pty Ltd | Method and system FPOR transferring data to improve responsiveness when sending large data sets |
US8976190B1 (en) | 2013-03-15 | 2015-03-10 | Pme Ip Australia Pty Ltd | Method and system for rule based display of sets of images |
US10070839B2 (en) | 2013-03-15 | 2018-09-11 | PME IP Pty Ltd | Apparatus and system for rule based visualization of digital breast tomosynthesis and other volumetric images |
US11244495B2 (en) | 2013-03-15 | 2022-02-08 | PME IP Pty Ltd | Method and system for rule based display of sets of images using image content derived parameters |
US9411787B1 (en) | 2013-03-15 | 2016-08-09 | Thousandeyes, Inc. | Cross-layer troubleshooting of application delivery |
US10540803B2 (en) | 2013-03-15 | 2020-01-21 | PME IP Pty Ltd | Method and system for rule-based display of sets of images |
US11183292B2 (en) | 2013-03-15 | 2021-11-23 | PME IP Pty Ltd | Method and system for rule-based anonymized display and data export |
US9037643B2 (en) * | 2013-03-15 | 2015-05-19 | Edgecast Networks, Inc. | Dynamic tag management for optimizing content delivery |
US9288128B1 (en) * | 2013-03-15 | 2016-03-15 | Google Inc. | Embedding network measurements within multiplexing session layers |
US10320628B2 (en) * | 2013-06-19 | 2019-06-11 | Citrix Systems, Inc. | Confidence scoring of device reputation based on characteristic network behavior |
US20150005968A1 (en) * | 2013-07-01 | 2015-01-01 | Enernoc, Inc. | Apparatus and method for determining device participation in an energy management program |
US8788703B1 (en) * | 2013-08-05 | 2014-07-22 | Iboss, Inc. | Content caching |
US8972513B2 (en) | 2013-08-05 | 2015-03-03 | Iboss, Inc. | Content caching |
US10362081B2 (en) | 2013-08-30 | 2019-07-23 | Citrix Systems, Inc. | Methods and systems for quantifying the holistic quality of experience for internet multimedia |
WO2015081988A1 (en) * | 2013-12-03 | 2015-06-11 | Telefonaktiebolaget Lm Ericsson (Publ) | Performance metric of a system conveying web content |
US9608874B2 (en) * | 2013-12-05 | 2017-03-28 | At&T Intellectual Property I, L.P. | Methods and apparatus to identify network topologies |
US9900393B2 (en) * | 2014-01-08 | 2018-02-20 | Veex Inc. | Systems and methods for dynamically managing capabilities on network monitoring devices |
CN104767837B (en) * | 2014-01-08 | 2018-08-24 | 阿里巴巴集团控股有限公司 | A kind of method and device of identification agent IP address |
US10212194B2 (en) * | 2014-01-20 | 2019-02-19 | Google Llc | Server controlled throttling of client to server requests |
US9887914B2 (en) * | 2014-02-04 | 2018-02-06 | Fastly, Inc. | Communication path selection for content delivery |
US20150271071A1 (en) | 2014-03-18 | 2015-09-24 | Fluke Corporation | Methods and apparatus to determine network delay with location independence |
US9854053B1 (en) * | 2014-03-24 | 2017-12-26 | Amazon Technologies, Inc. | Providing faster data access using multiple caching servers |
US20150281261A1 (en) * | 2014-03-26 | 2015-10-01 | International Business Machines Corporation | Detecting proxy-based communications |
US9766681B2 (en) * | 2014-06-17 | 2017-09-19 | Empire Technology Development Llc | Operations related to a retransmission buffer |
US10732994B2 (en) * | 2014-06-30 | 2020-08-04 | Mark Spence | Distributed process framework |
US10296973B2 (en) * | 2014-07-23 | 2019-05-21 | Fortinet, Inc. | Financial information exchange (FIX) protocol based load balancing |
JP6199844B2 (en) * | 2014-10-31 | 2017-09-20 | 日本電信電話株式会社 | Suspicious part estimation device and suspected part estimation method |
US9877214B1 (en) * | 2014-12-03 | 2018-01-23 | Sprint Spectrum L.P. | Passive quality of experience measurements |
US9959332B2 (en) * | 2015-01-21 | 2018-05-01 | Futurewei Technologies, Inc. | System and method for massively parallel processor database |
US10050831B2 (en) | 2015-02-26 | 2018-08-14 | Verisign, Inc. | Query latency of a DNS service |
US10135890B2 (en) * | 2015-03-06 | 2018-11-20 | Sony Interactive Entertainment LLC | Latency-dependent cloud input channel management |
US9794372B2 (en) * | 2015-04-07 | 2017-10-17 | At&T Intellectual Property I, L.P. | Connection management service |
US9847926B2 (en) * | 2015-04-15 | 2017-12-19 | Teachers Insurance And Annuity Association Of America | Presenting application performance monitoring data in distributed computer systems |
US11599672B2 (en) | 2015-07-31 | 2023-03-07 | PME IP Pty Ltd | Method and apparatus for anonymized display and data export |
US9984478B2 (en) | 2015-07-28 | 2018-05-29 | PME IP Pty Ltd | Apparatus and method for visualizing digital breast tomosynthesis and other volumetric images |
US9954759B2 (en) | 2015-07-29 | 2018-04-24 | International Business Machines Corporation | Detecting proxy-based communications |
US10838510B2 (en) | 2016-02-12 | 2020-11-17 | Hewlett Packard Enterprise Development Lp | Generating modified keyboard data received from a client device to reduce unintended key repetition |
US20170295099A1 (en) * | 2016-04-11 | 2017-10-12 | Arista Networks, Inc. | System and method of load balancing across a multi-link group |
WO2017196216A1 (en) * | 2016-05-12 | 2017-11-16 | Telefonaktiebolaget Lm Ericsson (Publ) | A monitoring controller and a method performed thereby for monitoring network performance |
US10659325B2 (en) | 2016-06-15 | 2020-05-19 | Thousandeyes, Inc. | Monitoring enterprise networks with endpoint agents |
US10671520B1 (en) | 2016-06-15 | 2020-06-02 | Thousandeyes, Inc. | Scheduled tests for endpoint agents |
US11188941B2 (en) | 2016-06-21 | 2021-11-30 | The Nielsen Company (Us), Llc | Methods and apparatus to collect and process browsing history |
WO2018010824A1 (en) * | 2016-07-15 | 2018-01-18 | Telefonaktiebolaget Lm Ericsson (Publ) | Determining a service level in a communication network |
US10412198B1 (en) * | 2016-10-27 | 2019-09-10 | F5 Networks, Inc. | Methods for improved transmission control protocol (TCP) performance visibility and devices thereof |
US10554598B2 (en) * | 2016-12-09 | 2020-02-04 | Microsoft Technology Licensing, Llc | Accessibility processing when making content available to others |
US11144423B2 (en) | 2016-12-28 | 2021-10-12 | Telefonaktiebolaget Lm Ericsson (Publ) | Dynamic management of monitoring tasks in a cloud environment |
US10412616B1 (en) | 2017-07-11 | 2019-09-10 | Sprint Communications Company, L.P. | Equalized data latency for user applications in a wireless data network |
EP3673591B1 (en) | 2017-08-24 | 2021-07-21 | Telefonaktiebolaget LM Ericsson (publ) | Method and apparatus for enabling active measurements in internet of things (iot) systems |
US10909679B2 (en) | 2017-09-24 | 2021-02-02 | PME IP Pty Ltd | Method and system for rule based display of sets of images using image content derived parameters |
US10461992B1 (en) * | 2017-09-26 | 2019-10-29 | Amazon Technologies, Inc. | Detection of failures in network devices |
CN108011778B (en) * | 2017-11-30 | 2020-08-04 | 北京润科通用技术有限公司 | Method and device for acquiring message transmission delay time |
US11223689B1 (en) | 2018-01-05 | 2022-01-11 | F5 Networks, Inc. | Methods for multipath transmission control protocol (MPTCP) based session migration and devices thereof |
CN108418656B (en) * | 2018-01-17 | 2021-01-08 | 南京航空航天大学 | LwIP delay ACK timer period self-adaption method based on data statistics |
GB2568325B (en) * | 2018-01-25 | 2020-05-20 | Spatialbuzz Ltd | Examining latency in communications networks |
US10848402B1 (en) | 2018-10-24 | 2020-11-24 | Thousandeyes, Inc. | Application aware device monitoring correlation and visualization |
US11032124B1 (en) | 2018-10-24 | 2021-06-08 | Thousandeyes Llc | Application aware device monitoring |
US11050652B2 (en) | 2018-11-01 | 2021-06-29 | Microsoft Technology Licensing, Llc | Link fault isolation using latencies |
US10567249B1 (en) | 2019-03-18 | 2020-02-18 | Thousandeyes, Inc. | Network path visualization using node grouping and pagination |
US11496365B2 (en) * | 2019-06-17 | 2022-11-08 | Cyxtera Data Centers, Inc. | Automated access to racks in a colocation data center |
US10805144B1 (en) * | 2019-06-18 | 2020-10-13 | Cisco Technology, Inc. | Monitoring interactions between entities in a network by an agent for particular types of interactions and indexing and establishing relationships of the components of each interaction |
WO2021050269A1 (en) * | 2019-09-10 | 2021-03-18 | Arris Enterprises Llc | User interface for configuring device-specific iot applications |
US11461213B2 (en) * | 2019-10-31 | 2022-10-04 | Microsoft Technology Licensing, Llc | Mitigating slow instances in large-scale streaming pipelines |
WO2021167659A1 (en) * | 2019-11-14 | 2021-08-26 | Trideum Corporation | Systems and methods of monitoring and controlling remote assets |
US11553032B2 (en) * | 2021-05-05 | 2023-01-10 | Jpmorgan Chase Bank, N.A. | System and method for toolchain integration in application availability monitoring |
Family Cites Families (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4789948A (en) | 1985-09-13 | 1988-12-06 | Hughes Aircraft Company | Method and apparatus for determining communications link quality and receiver tracking performance |
US4918623A (en) | 1985-10-04 | 1990-04-17 | Codex Corporation | Testing the performance of a communication line between two modems using modem processor |
US5095444A (en) | 1989-12-21 | 1992-03-10 | Legent Corporation | System and method for measuring inter-nodal transmission delays in a communications network |
US5870561A (en) * | 1996-03-15 | 1999-02-09 | Novell, Inc. | Network traffic manager server for providing policy-based recommendations to clients |
US5787253A (en) | 1996-05-28 | 1998-07-28 | The Ag Group | Apparatus and method of analyzing internet activity |
US5781703A (en) | 1996-09-06 | 1998-07-14 | Candle Distributed Solutions, Inc. | Intelligent remote agent for computer performance monitoring |
US6014381A (en) * | 1996-09-13 | 2000-01-11 | Sony Corporation | System and method for distributing information throughout an aircraft |
US6046980A (en) | 1996-12-09 | 2000-04-04 | Packeteer, Inc. | System for managing flow bandwidth utilization at network, transport and application layers in store and forward network |
US6035418A (en) | 1996-12-13 | 2000-03-07 | International Business Machines Corporation | System and method for improving resource utilization in a TCP/IP connection management system |
US5732218A (en) | 1997-01-02 | 1998-03-24 | Lucent Technologies Inc. | Management-data-gathering system for gathering on clients and servers data regarding interactions between the servers, the clients, and users of the clients during real use of a network of clients and servers |
CA2202572C (en) * | 1997-04-14 | 2004-02-10 | Ka Lun Eddie Law | A scaleable web server and method of efficiently managing multiple servers |
US6047322A (en) | 1997-05-27 | 2000-04-04 | Ukiah Software, Inc. | Method and apparatus for quality of service management |
US6006260A (en) | 1997-06-03 | 1999-12-21 | Keynote Systems, Inc. | Method and apparatus for evalutating service to a user over the internet |
US6006264A (en) * | 1997-08-01 | 1999-12-21 | Arrowpoint Communications, Inc. | Method and system for directing a flow between a client and a server |
US6018516A (en) | 1997-11-14 | 2000-01-25 | Packeteer, Inc. | Method for minimizing unneeded retransmission of packets in a packet communication environment supporting a plurality of data link rates |
US6078953A (en) * | 1997-12-29 | 2000-06-20 | Ukiah Software, Inc. | System and method for monitoring quality of service over network |
US6012096A (en) * | 1998-04-23 | 2000-01-04 | Microsoft Corporation | Method and system for peer-to-peer network latency measurement |
WO2000019664A2 (en) * | 1998-09-30 | 2000-04-06 | Netscout Service Level Corporation | Managing computer resources |
US6138157A (en) | 1998-10-12 | 2000-10-24 | Freshwater Software, Inc. | Method and apparatus for testing web sites |
US6078957A (en) | 1998-11-20 | 2000-06-20 | Network Alchemy, Inc. | Method and apparatus for a TCP/IP load balancing and failover process in an internet protocol (IP) network clustering system |
CN1700657A (en) * | 1998-11-24 | 2005-11-23 | 尼克桑公司 | Apparatus and method for collecting and analyzing communications data |
US6789050B1 (en) * | 1998-12-23 | 2004-09-07 | At&T Corp. | Method and apparatus for modeling a web server |
US6560648B1 (en) * | 1999-04-19 | 2003-05-06 | International Business Machines Corporation | Method and apparatus for network latency performance measurement |
US6662223B1 (en) * | 1999-07-01 | 2003-12-09 | Cisco Technology, Inc. | Protocol to coordinate network end points to measure network latency |
US6449739B1 (en) | 1999-09-01 | 2002-09-10 | Mercury Interactive Corporation | Post-deployment monitoring of server performance |
-
2000
- 2000-12-21 US US09/740,804 patent/US7937470B2/en active Active
-
2001
- 2001-12-20 WO PCT/US2001/050418 patent/WO2002079903A2/en not_active Application Discontinuation
- 2001-12-20 AU AU2001297721A patent/AU2001297721A1/en not_active Abandoned
Also Published As
Publication number | Publication date |
---|---|
WO2002079903A3 (en) | 2003-01-09 |
AU2001297721A1 (en) | 2002-10-15 |
US7937470B2 (en) | 2011-05-03 |
US20020120727A1 (en) | 2002-08-29 |
WO2002079903A2 (en) | 2002-10-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7937470B2 (en) | Methods of determining communications protocol latency | |
US6738813B1 (en) | System and method for monitoring performance of a server system using otherwise unused processing capacity of user computing devices | |
US6973490B1 (en) | Method and system for object-level web performance and analysis | |
US6625648B1 (en) | Methods, systems and computer program products for network performance testing through active endpoint pair based testing and passive application monitoring | |
US7277938B2 (en) | Method and system for managing performance of data transfers for a data access system | |
US6928471B2 (en) | Method and apparatus for measurement, analysis, and optimization of content delivery | |
US8135828B2 (en) | Cooperative diagnosis of web transaction failures | |
US6041041A (en) | Method and system for managing data service systems | |
EP1367771B1 (en) | Passive network monitoring system | |
US7313141B2 (en) | Packet sequence number network monitoring system | |
US6941358B1 (en) | Enterprise interface for network analysis reporting | |
US20060029016A1 (en) | Debugging application performance over a network | |
US7693742B1 (en) | System, method and computer program product for a network analyzer business model | |
JP4065398B2 (en) | Method and apparatus for measuring internet router traffic | |
Luo et al. | Design and Implementation of TCP Data Probes for Reliable and Metric-Rich Network Path Monitoring. | |
US6297823B1 (en) | Method and apparatus providing insertion of inlays in an application user interface | |
WO2002082727A1 (en) | Method for collecting a network performance information, computer readable medium storing the same, and an analysis system and method for network performance | |
Marshak et al. | Evaluating web user perceived latency using server side measurements | |
US10382290B2 (en) | Service analytics | |
Repp et al. | A cross-layer approach to performance monitoring of web services | |
Darst et al. | Measurement and management of internet services | |
Borzemski et al. | An Empirical Study of Web Quality: Measuring the Web from Wroclaw University of Technology Campus. | |
Shan et al. | A case study of IP network monitoring using wireless mobile devices | |
JP3611823B2 (en) | Network performance monitoring apparatus and method | |
Agrawal et al. | Monitoring infrastructure for converged networks and services |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A2 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PH PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG UZ VN YU ZA ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A2 Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
AK | Designated states |
Kind code of ref document: A3 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PH PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG UZ VN YU ZA ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A3 Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8642 |
|
122 | Ep: pct application non-entry in european phase | ||
COP | Corrected version of pamphlet |
Free format text: PAGES 1/11-11/11, DRAWINGS, REPLACED BY NEW PAGES 1/11-11/11; DUE TO LATE TRANSMITTAL BY THE RECEIVING OFFICE |
|
NENP | Non-entry into the national phase |
Ref country code: JP |
|
WWW | Wipo information: withdrawn in national office |
Country of ref document: JP |