US 20050138204 A1
A unified policy management system for an organization including a central policy server and remotely situated policy enforcers. A central database and policy enforcer databases storing policy settings are configured as LDAP databases adhering to a hierarchical object oriented structure. Such structure allows the policy settings to be defined in an intuitive and extensible fashion. Changes in the policy settings made at the central policy server are automatically transferred to the policy enforcers for updating their respective databases. Each policy enforcer collects and transmits health and status information in a predefined log format and transmits it to the policy server for efficient monitoring by the policy server. For further efficiencies, the policy enforcement functionalities of the policy enforcers are effectively partitioned so as to be readily implemented in hardware. The system also provides for dynamically routed VPNs where VPN membership lists are automatically created and shared with the member policy enforcers. Updates to such membership lists are also automatically transferred to remote VPN clients. The system further provides for fine grain access control of the traffic in the VPN by allowing definition of firewall rules within the VPN. In addition, policy server and policy enforcers may be configured for high availability by maintaining a backup unit in addition to a primary unit. The backup unit become active upon failure of the primary unit.
1. A computer network comprising:
a first edge device coupled to a first private network, the first edge device configured to create a first table with information of member networks reachable through the first edge device, the first table being stored in a first database;
a second edge device coupled to a second private network, the second edge device configured to create a second table with information of member networks reachable through the second edge device, the second table being stored in a second database;
wherein, the first and second edge devices enable secure communication between the first and second private networks, and the first edge device shares the first table with the second edge device and the second edge device shares the second table with the first edge device.
2. The computer network of
receiving a new route information;
storing the new route information in the first database; and
transmitting a portion of the new route information to the second edge device.
3. The computer network of
4. The computer network of
receiving the portion of the new route information;
accessing the first database based on the portion of the new route information;
retrieving the new route information from the first database; and
storing the retrieved route information in the second database.
5. The computer network of
6. The computer network of
7. The computer network of
8. The computer network of
9. In a computer network including a first edge device coupled to a first private network and a second edge device coupled to a second private network, the first and second edge devices enabling secure communication between the first and second private networks, a method for gathering membership information comprising:
creating a first table with information of member networks reachable through the first edge device,
storing the first table in a first database;
creating a second table with information of member networks reachable through the second edge device;
storing the second table in a second database;
sharing the first table with the second edge device; and
sharing the second table with the first edge device.
10. The method of
receiving a new route information;
storing the new route information in the first database; and
transmitting a portion of the new route information to the second edge device.
11. The method of
12. The method of
receiving the portion of the new route information;
accessing the first database based on the portion of the new route information;
retrieving the new route information from the first database; and
storing the retrieved route information in the second database.
13. The method of
14. The method of
15. The method of
16. The method of
This application claims the benefit of U.S. provisional applications 60/138,849, 60/138,850, 60/139,033, 60/139,034 60/139,035, 60/139,036, 60/139,038, 60/139,042, 60/139,043, 60/139,044, 60/139,047, 60/139,048, 60/139,049, 60/139,052, 60/139,053, all filed on Jun. 10, 1999, and U.S. provisional application 60/139,076, filed on Jun. 11, 1999, the contents of all of which are incorporated herein by reference.
The present invention relates to computer networks, and more particularly, to devices and methods for providing efficient configuration, management, and updating of virtual private networks extending over remote sites across the Internet.
The growth and proliferation of computers and computer networks allow businesses to efficiently communicate with their own components as well as with their business partners, customers, and suppliers. However, the flexibility and efficiencies provided by such computers and computer networks come with increasing risks, including security breaches from outside the corporation, accidental release of vital information from within it, and inappropriate use of the LAN, WAN, Internet, or extranet.
In managing the growth of computer networks as well as addressing the various security issues, network managers often turn to network policy management services such as firewall protection, Network Address Translation, spam email filtering, DNS caching, Web caching, virtual private network (VPN) organization and security, and URL blocking for keeping network users from accessing certain Web sites through use of the organization's ISP. Each policy management service, however, generally requires a separate device that needs to be configured, managed, and monitored. Furthermore, as an organization grows and spreads across multiple locations, the devices maintained also multiplies, multiplying the associated expenditures and efforts to configure, manage, and monitor the devices.
The solution to this problem is not as simple as just integrating multiple network policy management functions into a single device at each location and allowing each location to share its policy information with other locations. In fact, there are many obstacles and challenges in adopting such an approach. One of these challenges is devising a scheme for efficient configuration, management, and updating of VPNs extending over remote sites separated by the Internet. Typical Internet Protocol Security (IPSec) VPN tunnels are point-to-point entities with static reachability information, that is, information about which fellow VPN members they can reach for the networks behind each VPN gateway. Encrypting or otherwise tunneling traffic between many sites that have potentially different dynamic routing protocols over an IPSec tunnel can therefore be problematic. It may also be problematic to set up a fully meshed VPN where every site has full connectivity to every other site if there are a large number of sites. Furthermore, VPN definitions are typically an association of source and destination network addresses that allow unrestricted access between the networks in the VPN, and providing fine grained access control to such traffic may be difficult.
Accordingly, there remains a need in the art for a network management solution that overcomes these and other obstacles of the prior art.
The present invention is directed to a unified policy management system allowing the efficient configuration, management, and updating of VPNs extending over remote sites separated by the Internet. The system allows each endpoint in a VPN tunnel to aggregate and abstract out the reachability information of the networks associated with each endpoint. This information is then shared with all the other tunnel endpoints in the same VPN. Furthermore, the system provides a hierarchical organization of VPNs facilitating the creation of fully-meshed VPNs. In addition, access control rules may be defined for a VPN to allow users to have fine grain control over the traffic flowing through the VPN.
According to one embodiment of the invention, a computer network includes a first edge device coupled to a first private network and a second edge device coupled to a second private network. The first and second edge devices preferably act as VPN tunnel endpoints allowing secure communication between the first and second private networks. In addition, the first edge device is configured to create a first table with information of member networks reachable through the first edge device, and the second edge device is configured to create a second table with information of member networks reachable through the second edge device. The first and edge devices share their membership information with each other, allowing the creation of VPNs whose member lists are dynamically compiled.
In one particular aspect of the invention, the communication between the first and second private networks is managed according to a security policy associated with the member networks. The security policy is defined for a security policy group, referred to as a VPN cloud, providing hierarchical organization of the group. The VPN cloud includes member networks (hosts), users allowed to access the member networks, and a rule controlling access to the member networks. The hierarchical organization provided by the VPN clouds thus allows the network administrator to create fully meshed VPNs. The network administrator need no longer manually configure each possible connection in the VPN, but only need to create a VPN cloud and specify the sites, users, and rules to be associated with the VPN. Each connection is then configured based on the configuration specified for the VPN cloud. The hierarchical organization thus facilitates the setup of a VPN with a large number of sites.
In another aspect of the invention, the rule in the VPN is a firewall rule providing access control of the traffic among the member networks. Such firewall rules allow the administrator to have fine grained access control over the traffic that flows through the VPN, all within the realm of the encrypted access provided by such VPN.
These and other features, aspects and advantages of the present invention will be more fully understood when considered with respect to the following detailed description, appended claims and accompanying drawings wherein:
I. Unified Policy Management System Architecture
According to one example, local network 102 connects users and resources, such as workstations, servers, printers, and the like, at a first location of the organization, such as the organization's headquarters, and local network 104 connects users and resources at a second location of the organization, such as a branch office. Furthermore, local network 106 connects users and resources of a customer of the organization requiring special access to the organization's users and resources. Authorized dial-up network users 114 of the organization are respectively situated at remote locations from the first and second local networks, and also require special access to the organization's users and resources. Furthermore, web surfers 112 communicate with the organization's web server 120 over the public Internet 108 and access the organization's web site.
Local network 102 includes a policy server 122 for defining and managing network services and policies for the organization. The network policies are a set of rules and instructions that determine the network's operation, Such as firewall, VPN, bandwidth, and administration policies. The firewall policies decide the network traffic that is to be allowed to flow from the public Internet 108 into the local networks 102, 104, and the traffic that is to be blocked. The bandwidth policies determine the kind of bandwidth that is to be allocated to the traffic flowing through the local networks. The VPN policies determine the rules for implementing multiple site connectivity across the local networks. The administration policies decide the users that have access to administrative functions, the type of administrative functions allocated to these users, and the policy enforcers 124, 126 on which these users may exercise such administrative functions. The firewall, VPN, bandwidth, and administration policies for the entire organization are preferably stored in a policy-server database 130 maintained by the policy server 122.
Each local network 102, 104 also includes an edge device, referred to as a policy enforcer 124, 126, for controlling access to the network. Each policy enforcer 124, 126 manages the network policies and services for the users and resources of their respective local networks 102, 104, as permitted by the policy server 122. Respective portions of the policy server database 130 are copied to the policy enforcer databases 132, 134 for allowing the policy enforcers to manage the network policies and services for the local networks 102, 104.
According to one embodiment of the invention, the policy server 122 and policy enforcers 124, 126 may be implemented in a similar fashion as the FORT KNOX series of policy routers made by Alcatel Internetworking, Inc., of Milpitas, Calif.
II. Object Model for Network Policy Management
According to one embodiment of the invention, the policy server database 130 and policy enforcer databases 132, 134 are LDAP databases adhering to a unified hierarchical object oriented structure. The LDAP directory service model is based on entries where each entry is a collection of attributes referenced by a distinguished name (DN). Each of the attributes includes a type and one or more values. The type is typically a mnemonic string, such as “o” for organization, “c” for country, or “mail” for email address. The values depend on the type of attribute. For example, a “mail” attribute may contain the value “firstname.lastname@example.org.” A “jpegPhoto” attribute may contain a photograph in binary JPEG/JFIF format. Additional details of the LDAP directory service model are defined in RFC 1777 “The Lightweight Directory Access Protocol” (W. Yeong, T. Howes, and Kille, Network Working Group, March 1995) and “LDAP Programming: Directory-enabled Applications with Lightweight Directory Access Protocol” (T. Howes, and M. Smith, Macmillan Technical Publishing, 1997), incorporated herein by reference.
The entries in the LDAP database are preferably arranged in a hierarchical tree-like structure reflecting political, geographic, and/or organizational boundaries. Entries representing countries appear at the top of the tree. Below them are entries representing states or national organizations. Below the states or national organizations may be entries representing people, organization units, printers, documents, and the like.
As illustrated in
Users 206 are preferably associated with a user domain providing a secure and efficient means of authenticating the user. Each user domain has a single policy enforcer who is authorized to authenticate the user. Thus, user domains ensure that the authenticating agent is generally located in the same local network as the user. This helps eliminate the cost of network dependency or network latency during the user authentication process. It should be noted, however, that users may also constitute authorized dial-up users 114 and users from the customer network 106. These users contact a remote authenticating agent which proxies the authentication back to the appropriate policy enforcer.
Hosts 208 are the various networks present in an organization. For instance, a particular LAN subnet may be specified as a host in the system. Hosts 208 are preferably organized based on their physical locations within the organization. A host's physical location is identified by the device (policy enforcer) 204 associated with the host.
Services 210 reflect the various services provided by the policy server 122. Such services include, for example, multimedia streaming/conferencing, information retrieval, security and authentication, database applications, mail applications, routing applications, standard communication protocols, and the like. Attributes associated with each service preferably include a service name, description, type (e.g. HTTP, HTTPS, FTP, TELNET, SMTP, Real Networks, and the like), and group.
Devices 204 are the policy enforcers 124, 126 at the edge of a particular local network. Each device/policy enforcer preferably includes users 206 and a host/network 208 that is managed by the policy enforcer.
Time 220 is another dimension in controlling access to the network resources. Various time objects covering a range of times may be created and used in creating the firewall policies.
Similar to resources, network policies are also preferably defined in terms of objects for a more efficient and intuitive definition of the policies. Policies are defined by the administrators and implemented by the policy enforcers 124, 126 on the network traffic flowing between the public Internet 108 and the local networks 102 and 104.
According to one embodiment of the invention, a policy object 222 includes a bandwidth policy 224, firewall policy 226, administration policy 228, and VPN policy 230. The VPN policy 230 defines a security policy for the member networks and includes one or more VPN clouds 232. Each VPN cloud 232 is an individual VPN or a group of VPNs defining a security policy group which includes a list of sites 234 and users 236 who can communicate with each other. A site is preferably a set of hosts/networks physically located behind one of the policy enforcers 124, 126. In other words, a site is a definition of a network which includes the policy enforcer that is associated with it. The policy enforcers for the sites act as VPN tunnel endpoints once the hosts under the sites start communicating. These communications are governed by a set of rules 238 configured for each VPN cloud. The rules 238 may govern, among other things, VPN access permissions and security features such as the level of encryption and authentication used for the connectivity at the network layer.
The object oriented structure of
III. Policy-Based Network Architecture
Referring again to the management module 302, the management module 302 preferably includes four sub-modules aiding in the centralized control, namely, a centralized management sub-module 306, policy management sub-module 308, secure role-based management sub-module 310, and multiple site connectivity management sub-module 312.
The centralized management sub-module 306 enables a network administrator to install and manage individual policy enforcers from a central location. The network administrator preferably uses a web-based graphical user interface to define the policy enforcer's network configuration and monitor various aspects of the device, such as device health, device alarms, VPN connection status, and the like.
The policy management sub-module 308 provides the network administrator with the ability to create policies that span multiple functional aspects of the policy enforcer (e.g. firewall, bandwidth management, and virtual private networks), multiple resources (e.g. users, hosts, services and time), and multiple policy enforcers.
The secure role-based management sub-module 310 provides role-based management to enable administrators to delegate administrative responsibilities to other administrators. This sub-module preferably provides for maximum security when it comes to accessing the management functions.
The multiple site connectivity management sub-module 312 allows the network administrator to set-up secure communication channels between two or more remote sites. In doing so, this sub-module leverages the centralized management sub-module 306, policy management sub-module 308, dynamic routing capabilities of the policy enforcers 124, 126, and the management infrastructure to provide virtual private networks across the enterprise with fine grained access control.
Once connected, the policy server installation wizard 404 invokes the interactive user interface to assist the administrator in setting up the policy server 122. Among other things, the policy server installation wizard 404 prompts the administrator to specify a server name, server IP address, and router IP address. Furthermore, the policy server installation wizard 404 prompts the administrator to select one of various default policies for creating default firewall, VPN, bandwidth, and administrator policies. These policies are then replicated on each new policy enforcer registering with the policy server 122.
The centralized management sub-module 306 further includes a policy enforcer installation wizard 406 providing an interactive user interface to aid the installation of the policy enforcers 124, 126. As with the installation of the policy server 122, the access to the wizard 406 is preferably web-based using the network administrator's personal computer.
Once connected, the policy enforcer installation wizard 406 invokes the interactive user interface to assist the network administrator in setting up a particular policy enforcer 124, 126. Among other things, the policy enforcer installation wizard 464 prompts the administrator to specify the policy server IP address, policy enforcer IP address, and router IP address. The policy enforcer then registers with the policy server 122 by invoking a URL on the policy server with basic bootstrap information of its own. The registration of the policy enforcer allows the initialization of the policy enforcer's database 132, 134 with the configuration information, as well as the monitoring of the policy enforcer's status and health by the policy server 122.
Prior to registering the policy enforcer with the policy server 122, the network administrator preferably pre-registers the policy enforcer on the policy server. Such pre-registering allows the creation of a placeholder node on the policy server for the policy enforcer data for when the policy enforcer does in fact register. In this regard, the centralized management sub-module 306 includes a configuration interface 410 allowing the pre-registration of a new policy enforcer.
Referring again to
Referring again to
Selection of the users tab 718 a causes a display of the user groups 722 defined for the system. New users may be added to the group by selecting a particular group and defining various attributes of the user such as a login name, full name, policy enforcer to which the user belongs, authentication scheme, password, and the like.
Selection of the devices tab 718 b causes a display of various device management icons for managing the policy server 122 and the policy enforcers 124, 126 as is illustrated in
The administrator may view information on all the policy enforcers 124, 126 by selecting icon 758. Information on a specific policy enforcer may be viewed by selecting a specific policy enforcer 760 under a particular device group 761. Such information includes system settings information 762, URL blocking information 764, spam list information 766, and the like, that is specific to the selected policy enforcer. For instance, selection of the policy enforcer's URL blocking information 764 icon causes a display of various categories 768 of URLs that the network administrator may select to block for the selected policy enforcer.
Selection of the hosts tab 718 c causes a display of various hosts (networks) of the system as is illustrated in
Selection of the services tab 718 d causes a display of various service groups supported by the policy server 122 as is illustrated in
Each service is associated with a name 784, description 786, and service type 788 (e.g. HTTP, HTTPS, FTP, TELNET, SMTP, Real Networks, and the like) Furthermore, each service is associated with a service group 790. Based on the type of service, additional information may also be specified for the service. For instance, for an HTTP service, the administrator may specify whether URL blocking 792 is to be enabled.
Selection of the time tab 718 e causes a display of various time group icons 794 covering a range of times to be used in the firewall policies as is illustrated in
Referring again to
Selection of a firewall tab 720 a causes a display of all the firewall policies defined for a particular policy domain including one or more policy enforcers. The network administrator decides the domain to which a policy enforcer is to belong during pre-registration of the policy enforcer. The interface allows the network administrator to view, add, and modify the various policies from the policy server 122 and effectuate the changes on the policy enforcers 124, 126 without the need to make such changes individually in each policy enforcer.
According to one embodiment of the invention, each firewall policy includes a policy identifier (ID) attribute 724 for identifying a particular policy rule in the list of policies. An order number attribute 726 for the policy rule indicates the sequence in which the policy is to be applied. In this regard, the policy enforcer 124, 126 for the local network takes one rule at a time, in sequence, compares it against the network traffic, and preferably applies the first rule that matches the network traffic.
Each firewall policy also includes a description attribute 728 for describing the firewall policy to be applied. For instance, the description may indicate that the policy allows spam blocking, URL blocking, VPN key management, and the like. An action flag attribute 730 indicates whether traffic is to be allowed or denied for the indicated policy. An active flag attribute 732 indicates whether the policy has been activated or de-activated. Thus, the network administrator may create a policy and activate it at a later time. A policy that has been de-activated preferably has no effect on the network traffic.
Each firewall policy further includes a user attribute 734, source attribute 736, service attribute 738, destination attribute (not shown), and time attribute (not shown). Each of these attributes is preferably represented by a group name or a resource name. The name acts as a pointer to an entry in the group root object 202 or resource root object of the LDAP database 130, 132, or 134.
Preferably, the user attribute 734 indicates the user groups and users that are eligible for the policy. The source attribute 736 indicates a point of origination of the network traffic associated with the user. The services attribute 738 indicates the services to the allowed or denied by the policy. The destination attribute indicates a specific LAN, WAN, DMS segment or specific hosts where the specified services are to be allowed or denied. For example, to configure SMTP pop services on a mail server, the host may be the IP address where the mail server is running, and the services specified is SMTP. The time attribute indicates a time slot in which the policy is to be effective, In addition to the above, each firewall policy also includes an authentication attribute (not shown) indicating an authentication scheme for the policy (e.g. none, LDAP, SecurID, RADIUS, WinNT, or all).
As illustrated in
Referring again to
Selection of the administration tab 720 d allows the display, addition, and modification of various administrative policies allowing a head network administrator to delegate administrative responsibilities to other administrators. In this regard, the head network administrator specifies administration policies that determine which users have access to what functions, and for what devices. Preferably the administration policies include similar attributes as the firewall rules except for the specification of a role attribute. Extra administrative privileges may be afforded to certain users depending on their role.
IV. Virtual Private Network Having Automatic Reachability Updating
Referring again to
Referring again to
The users in the VPN cloud are the users who may access the hosts associated with the sites 234. The users access the hosts as VPN clients using VPN client software installed in each user's personal computer as is described in further detail below.
Each VPN cloud 270 further includes a firewall rules node 276 including firewall rules to be applied all the connections in the cloud. The rules may govern, among other things, VPN access permissions, security features such as the level of encryption and authentication used for the connectivity at the network layer.
The hierarchical organization provided by the VPN clouds thus allows the network administrator to create fully meshed VPNs where every site within a VPN cloud has full connectivity with every other site. The network administrator need no longer manually configure each possible connection in the VPN, but only need to create a VPN cloud and specify the sites, users, and rules to be associated with the VPN. Each connection is then configured based on the configuration specified for the VPN cloud. The hierarchical organization thus facilitates the setup of a VPN with a large number of sites.
The network administrator preferably adds a new VPN cloud by actuating an add button 280. In response, the policy server 122 automatically creates the sites node 272, users node 274, and rules node 276 under the VPN cloud. The administrator then specifies the sites and users in the VPN.
According to one embodiment of the invention, the rules node 276 initially includes a default VPN rule 278 corresponding to the policy settings selected by the network administrator during setup of the policy server 122. The default VPN rule 278 allows unrestricted access between the hosts in the VPN.
The administrator may implement the access control within the VPN cloud by deleting the default rule 278 and adding specific firewall rules to the VPN. Such firewall rules allow the administrator to have fine grained access control over the traffic that flows through the VPN, all within the realm of the encrypted access provided by such VPN. The firewall rules are applied to the cleartext packet after it is decrypted or before it is encrypted.
According to one embodiment of the invention, the administrator selects the default rule 278 to effectuate such changes to the default rule. Selection of the default rule invokes a graphical user interface similar to the one illustrated in
Once a VPN cloud is configured, VPN membership information is dynamically created by the policy enforcers 124, 126 in the VPN. In this regard, each VPN site includes a tag identifying the hosts included in the site. At runtime, the policy enforcers 124, 126 for the respective sites associate IP addresses to the tag identifying the hosts in each site. This allows the IP addresses to be dynamically discovered without requiring static configuration of the IP addresses.
After the creation of the membership tables, any changes in the routing information is detected and notified to the member policy enforcers using a publish/subscribe process. The actual changes are retrieved by a policy enforcer by querying the LDAP database on the particular network that corresponds to the changed routing information.
When a network administrator wishes to add a new route to the private local network 102 connected to policy enforcer 124, the administrator submits, in step 241, the new route to a gated module 252 in the policy enforcer 124. This is typically done by configuring a downstream of the policy enforcer to have an additional network. This information is then propagated by standard routing protocols to the gated module 252 of the policy enforcer 124. For example, the policy server 122 may publish the new route to the policy enforcer 124 with which the new route is to be associated. The route may be specified, for example, by an LDAP statement such as “LAN_Group@PR1,” which specifies a new route from a policy enforcer PR1 to a LAN named LAN_Group. The gated module 252, in step 242, writes the new route to a kernel 253 of the policy enforcer including a VPN driver 254 so that the policy enforcer 124 can properly direct appropriate messages along the new route. Furthermore, the gated module 252, in step 243, writes the new route to its LDAP database 132.
The gated module 252 also provides, in step 244, the name of the new route to a distinguished name monitor (DNMonitor) daemon 255 configured to listen for updates in the LDAP database 132. The DNMonitor in turn notifies, in steps 245 a, 245 b, a VPN daemon 256 and a policy deployment point (PDP) engine 257 of the change in the LDAP database 132. The PDP engine then updates the modules that enforce the policies, with the change.
The VPN daemon 256, in step 246, uses the route name to access the LDAP database 132 to get the complete route information, a list of all VPNs to which the new route belongs, and a list of all other policy routers connected to those VPNs. In step 247, the VPN daemon 256 proceeds to send the new route name to each of the other policy routers.
When policy router 126 receives a new route name from policy router 124, its network daemon 258, in step 248, accesses the LDAP database 132 in the sending policy router 124 to obtain the complete new route information. If the new route belongs to more than one VPN and has different parameters for the different VPNs, routers on the different VPNs retrieve different information corresponding to the individual VPNs.
In step 249, the network daemon 258 writes the new route information obtained in its own LDAP database 134 and provides it to its own DNMonitor module. As in the sending policy router 124, the DNMonitor module 259 in the receiving policy router 126 provides the new route information to its PDP engine 260 for updating its kernel 265 with the latest changes.
V. Virtual Private Network Having Automatic Updating of Client Reachability Information
Remote users communicate over the public Internet 108 with the other members of the VPN behind policy enforcers 124, 126, upon presenting appropriate credentials. These remote users access the private networks as VPN clients 140 using a VPN client software. According to one embodiment of the invention, the system allows the remote user to download a self-extracting executable which, upon execution, installs both the VPN client software and VPN reachability information unique to the remote user in the user's remote terminal.
Each policy enforcer 124, 126 preferably maintains a copy of the self-extracting executable of the VPN client software including a setup program and VPN reachability configuration template. The setup program allows the VPN client software to be installed on the VPN client 140. When downloading the self-extracting executable, the configuration template is replaced with the VPN reachability information that is specific to the downloading user.
According to another embodiment of the invention, the system allows the VPN client 140 to download a self-extracting executable which, upon execution, only installs the VPN reachability information that is unique to the user. According to this embodiment, the VPN client software is already installed on the VPN client 140. In this scenario, the setup program allows the installation of the reachability information that is specific to the downloading user, on the VPN client 140.
According to a third embodiment of the invention, the system allows the VPN client 140 to automatically download the VPN reachability information each time it connects to the policy enforcer 124, 126. Thus, VPN reachability information is kept up-to-date for each VPN client 140. Once a VPN session is established, the connection between the VPN client 140 and the policy enforcer is assumed to already be secure. The VPN client preferably makes a common gateway interface (CGI) query to a web server running on the policy enforcer, and downloads the current VPN reachability information from the corresponding LDAP database.
The self-extracting executable 290 preferably includes an executable setup file 292 for installing the VPN client software and/or the VPN configuration information. The setup file 292 preferably forms a static portion 298 of the self-extracting executable since this information does not change based on the downloading VPN client. The self-extracting executable 290 further includes VPN configuration file templates for the VPN reachability information 294 and the VPN client's preshared key information 296. The VPN reachability information 294 and the VPN client's preshared key 296 preferably form a dynamic portion 299 of the self-extracting executable 290 since this information changes based on the downloading VPN client. The self-extracting executable 290 is then saved as a template file in the policy enforcers 124, 126 and is ready to the downloaded by the remote users.
In step 334, the policy enforcer replaces the dynamic portion 299 of the self-extracting executable 290 with the VPN reachability information and preshared key that is unique to the VPN client. The newly generated self-extracting executable is then downloaded to the VPN client 140 in step 336. When the executable is run, it either installs the VPN client software and/or the VPN reachability information.
Similar techniques may also be used for downloading a new and updated copy of the VPN configuration information to the VPN client each time the client connects to the policy enforcer and negotiates a session key. In addition, the user may obtain the latest configuration of the VPN network by expressly requesting the policy enforcer for such information. Thus, the VPN client need not be reinstalled and reconfigured each time updates are made to the VPN reachability information.
VI. Integated Policy Enforcer
According to one embodiment of the invention, the functionalities of the policy enforcer 124, 126 for policy enforcement are partitioned for effective hardware implementation. However, it should be apparent to one skilled in the art that some or all of the functionalities may be implemented in software, hardware, or various combinations thereof.
In practice, an incoming packet is matched against the stream table 506 for determining if a matching entry already exists in the table. If not, a new entry is added. The stream table preferably includes enough portions of the packet to uniquely identify a stream. For example, in enforcing policies on IP layer three through layer four traffic, the stream table may store a source IP, destination IP, source port, destination port, and protocol number of the incoming packet.
The protocol classification engine 508 takes the new stream and obtains a detailed protocol decode for the stream. The policy engine 510 is then queried for the policy rules to be applied to the stream. Based on the policy rules returned by the policy engine 510, the packet forwarding module 504, IPSec engine 502, and/or the bandwidth management module 514 process the streams accordingly. The processing may be recursive until the packets in the stream have had all the actions specified by the policy rule set applied to them.
The policy enforcer also includes a statistics module 512 for collecting statistics on the packets forwarded through the local network as well as other status and resource usage information, and provides the same in logs and archives for sending to the policy server 122. According to one embodiment of the invention, the statistics module 512 keeps running byte counts of the packets passing through the network 102, 104. These byte counts may be automatically sorted by classes, such as classes based on certain resources (e.g. users, hosts, services), as well as by bytes that are blocked by policies and exceptions, such as firewall policies. In this regard, the statistics module 512 maintains in a cache a state table including a list of resources involved for each connection allowed through the firewall. For every packet flowing through the connection, the statistics module increments the packet and byte count for each of the resources in the list. The statistics module 512 then forwards the organized information to the policy server 122 which enters the information directly into tables organized by classes and aged out periodically.
A resource engine 604 maintains an up-to-date mapping of resource group names to member mappings. A policy rules database buffer 608 stores a current policy rule set to be applied by the policy engine 510. The policy rules stored in the buffer 608 are preferably in the original group-based rule specification format. Thus, the buffer 608 stores a rule created for a group in its group-based form instead of instantiating a rule for each member of the group.
A decision engine 606 includes logic to serve the incoming policy decision requests in the policy request table 602 by matching it against the policy rule set in the policy rules database buffer 608 based on the actual membership information obtained from the resource engine 604. The relevant group-based rule matching the traffic is then identified and decision bits in the stream table set for enforcing the corresponding actions. The decision bits thus constitute the set of actions to be performed on the packets of the stream. All packets matching the streams are then processed based on these decision bits. The decision engine may also specify an access control list (ACL) including a set of rules that allow/deny traffic, a DiffServ standard for providing a quality of service level to the traffic, and/or VPN implementation information.
Thus, the protocol classification engine 508 provides extensive layer three through layer seven protocol decode and packet classification, including complete identification of dynamic streams using a dynamically updated signature database compiled from scripted protocol definitions. As new protocols are defined in the future and/or users create their own custom applications with custom protocols, a need may arise to add recognition of these protocols to the protocol classification engine. The described protocol classification engine architecture allows such additions by simply adding a new scripted definition of the new protocol to the protocol classification engine without having to change the design each time a new protocol is added. This allows for custom protocol support and future protocol extensibility.
VII. Network Policy Logs and Statistics Aggregation
Referring again to
According to one embodiment of the invention, each policy enforcer 124, 126 maintains a log file with information collected about the flow of traffic through the policy enforcer as well as the status and usage of resources associated with the policy enforcer. All the log files follow a predefined common log format, preferably designed to create compact logs.
A user ID field 828 identifies the user transmitting the packet. The user ID may be mapped to an entry in the LDAP database 130, 132, or 134 for obtaining additional details about the user.
A status field 830 indicates the status of an operation and may include a result code, error code, and the like. For example, for a packet filter service, the status field may include a result code “p” if the packet was passed or code “b” if the packet was blocked.
An operation field 832 indicates codes for a type of operation conducted by the service. For instance, operations for a VPN service may include sending packets and receiving packets.
Operations for an FTP service may include GET and PUT operations. Operations for an HTTP service may include GET and POST operations.
In addition to the above, each log entry includes an in-bytes field 832 indicative of the number of bytes the policy enforcer received as a result of the activity, and an out-bytes field 834 indicative of the number of bytes transferred from the policy enforcer. Furthermore, a duration field 836 indicates the duration (e.g. in seconds) of the activity.
Certain fields of a particular log entry may be left blank if not applicable to a particular service. For instance, for an FTP download. Where there is no outgoing traffic, the out-bytes field is left blank. Furthermore, additional fields may be added based on the type of service being logged. For instance, for an HTTP activity, the URL that is accessed is also logged in the log entry. The additional fields are preferably appended to the end of the standard log format.
A person skilled in the art should recognize that additions, deletions, and other types of modifications may be made to the log format without departing from the spirit and the scope of the invention as long as the log format common to all the policy enforcers and is aimed in creating compact logs.
The log files created by the policy enforcers 124, 126 are transferred to the policy server 122 based on archive options set by the policy server. In this regard, the network administrator specifies a threshold size for the logs created by the policy enforcers upon selection of the policy server archive option 752 of
Once the policy server 122 receives the logs, it is stored in the archive database 318 preferably taking the form of an SQL database. The policy server reports module 316 queries this database to generate reports for each policy enforcer 124, 126. In addition, the logs may be exported in a format that may be interpreted by commercially available products such as WEBTRENDS, manufactured by WebTrends Corporation of Portland, Oreg.
The reports created by the reports module 316 include summary usage reports for the various resources including policy enforcers, users, services, hosts, and VPNs. For instance, the reports may include VPN summary reports, bandwidth summary reports, packet filter reports, and the like, for each policy enforcer.
The reports preferably show usage of each of the resources over a period time. The start and the end date for the report may be specified by the user. The user may further drill down on the time dimension and on the resource dimension for viewing specific times and specific resources. For instance, in creating the packet filter reports, the user may indicate a start and end time, source IP address, source port, destination IP address, and destination port. All packets meeting these criteria are then fetched from the archive database 318 and shown in a packet report.
VIII. Method for Selective LDAP Database Synchronization
According to one embodiment of the invention, the databases 130, 132, 134 in the unified policy management system of
The policy server 122 preferably stores the policy management information for all the policy enforcers in the policy server database 130. This information is organized in the databases 130 as one or more DNs with corresponding attributes. Appropriate portions of the policy server database are then copied to the policy enforcer databases 132, 134.
The policy server 122 may further maintain branch 268 storing information used only by the applications running on the server and not shared with any of the policy enforcers 124, 126. Likewise, policy enforcers 124, 126 may maintain a portion of branch 268 containing information used only by the applications on each of the policy enforcers and not shared elsewhere. Typically, the data stored in branch 268 is dynamically generated and used by the applications running on the corresponding server or agent.
Branch 270 is preferably only included in the LDAP tree for the policy server database 130 and stores logged policy management changes that may be propagated to the policy enforcers 124, 126. Such changes may include, for example, addition, deletion, or modifications of a user on a device, VPN cloud, bandwidth policy, or firewall policy made by the network administrator via the various graphical user interfaces described above. Such changes result in the updating of the policy database 130 where the corresponding DN of the LDAP tree is added, deleted, or modified. The policy server 122 further creates a log of the changes and stores them in branch 270 for later distribution to the policy enforcers 124, 126.
In step 422, the change made the administrator is reflected in the policy server database 130. In this regard, branches 264 and 266 of the LDAP tree are modified accordingly to reflect the change in the policy setting. Additionally, in step 424, the policy server 122 creates a log of the changes for the administrator for later processing and sending to the appropriate policy agent. In step 426, the policy server 122 updates the administrator's log DN 270 d to reflect the change. In the above example and as illustrated in
In step 428, the policy server 122 checks whether the changes made by the administrator are to be propagated to the appropriate policy enforcers 124, 126. As discussed above, the changes are preferably propagated upon actuation of an apply button from the administrator's graphical user interface.
If the apply button has been actuated, the policy server creates, in step 430, a log for each policy enforcer to whom the change is to be transmitted. In this regard, the policy server 122 collects all the changes made by the administrator as reflected in the values 270 g, 270 h of the apply attribute 270 f of the administrator's log DN 270 d. These changes are processed for each policy enforcer belonging to the administrator's domain. Such processing preferably involves picking the relevant changes and suitably modifying the DNs for the policy enforcer's LDAP. Such suitable modifications may be necessary, for instance, due to the differences in the tree structures in the policy server database 130 and the policy enforcer databases 132, 134. For instance, a change in the administrator's log may contain a DN that specifies the domain name of the policy enforcer. In applying this change to the policy enforcer, the domain name would not be specified in the DN since the policy enforcer's tree structure does not include a domain name.
The changes suitably modified for each policy enforcer's LDAP are then stored in a device log. Each policy enforcer's log DN 270 e is then modified to reflect the change to the transmitted to the particular policy enforcer. In the above example and as illustrated in
In step 432, the apply attribute 270 f for the administrator's log DN 270 d is then deleted from the LDAP tree. In step 434, the changes collected for each policy enforcer, as reflected in the values 270 j, 270 k of the apply attribute 270 i of the policy enforcer's log DN 270 e, are transmitted to the policy enforcer for updating its database 132, 134. The changes are sent to the policy enforcers preferably over the HTTPS channel.
In step 436, the policy server 122 checks whether the updates have been successful. In this regard, the policy server 122 waits to receive an acknowledgment from the policy enforcer that the updates have been successfully completed. Upon a positive response from the policy enforcer, the policy server 122 deletes the apply attribute 270 e for the policy enforcer's log DN 270 e. Otherwise, if the update was not successful (e.g. because the policy enforcer was down), the apply log is re-sent the next time another apply function is invoked. Alternatively, the failed policy enforcer transmits a request to the policy server 122 of the log of non-applied changes when it rejoins the network (e.g. by rebooting).
IX. State Transition Protocol for High Availability Units
According to one embodiment of the invention, the policy server 122, policy enforcers 124, 126, as well as other network devices may be configured for high availability by maintaining a backup unit in addition to a primary unit.
The primary unit 902 and the backup unit 904 are each similarly connected to other components 910, 912, 914 via ports 920 a, 920 b, 922 a, 922 b, 924 a, 924 b, respectively. These components 910, 912, 914 may be hubs, switches, connectors, or the like. Because the primary unit 902 and backup unit 904 provide similar services and functions and may be used interchangeably, each unit is preferably connected to the same components 910, 912, 914.
The parallel port cable 908 is preferably a conventional laplink cable designed to connect two parallel ports and allow communications between them. The primary unit 902 and the backup unit 904 preferably communicate with each other via TCP packets over the high-availability ports 906 a, 906 b. A point-to-point connection preferably exists between the primary unit 902 and the backup unit 904 over the high-availability ports 906 a, 906 b.
The primary unit 902 is preferably responsible for checking the status of its network ports for problems or failures. For example, if the primary unit 902 detects that one of its network ports is inoperable, e.g. port 922 a, the primary unit 902 then checks whether the corresponding port 922 b in the backup unit 904 is operational. Upon determining that the corresponding port 922 b in the backup unit 904 is operational, the primary unit 902 sends a request to the backup unit 904 to take over the system functions as the active unit. The primary unit 902 then relinquishes its role as the active unit and shuts itself down, allowing the backup unit 904 to take on the responsibilities of the primary unit 902. When the primary unit 902 restarts operation, the backup unit 904 receives a request from the primary unit 902 to relinquish its role as the active unit.
When the primary unit 902 is active and does not detect any defects in its ports, it continuously listens on the high-availability port 906 a to keep track of the status of the backup unit 904. The primary unit 902 continues to listen on the high-availability port 906 a for signals coming from the backup unit 904. When the backup unit 904 is up and running, it connects to the primary unit 902. Once the connection is made, the backup unit 904 begins sending heartbeats to the primary unit 902. The backup unit 904 continuously sends heartbeats to the primary unit 902 in predetermined intervals. According to one embodiment of the invention, the backup unit 904 sends a “Keep Alive” packet including a KEEP_ALIVE command to the primary unit 902 every one second.
The primary unit 902 responds to the “Keep Alive” packet by changing the command field of the packet to a KEEP_ALIVE_RESP command and re-transmitting the packet to the sender. If the backup unit 904 does not receive a response back from the primary unit 902 for a predetermined period of time (e.g. one second) for one “Keep Alive” packet, the backup unit 904 begins preparing to take over the active role. Preferably, the predetermined period should not be greater less than two consecutive “Keep Alive” packets.
Upon taking the role of the active unit, the backup unit 904 attempts to reestablish a connection with the primary unit 902 at regular intervals to determine whether the problem or failure in the primary unit has been cured. If the problem or failure has been cured, the backup unit 904 relinquishes its control to the primary unit 902 after setting the IP addresses of all the network interface cards to the assigned value.
In situations where the backup unit 904 takes over the active role from the primary unit 902, an alert/alarm is sent to the network administrator indicating such a change. In addition, if the primary unit 902 does not receive heartbeats from the backup unit 904, an alert/alarm is sent to the administrator indicating that the backup unit has failed.
A situation may arise when both the primary unit 902 and the backup unit 904 are fully functional, and the backup unit 904 desires to take over the active role. In this case, the backup unit 904 transmits a shut-down command to the primary unit 902 which then relinquishes control. The backup unit 904 continues its role as the active unit until the primary unit 902 transmits a request to the backup unit 904 to relinquish its active role.
According to one embodiment of the invention, the initial status determination protocol of each high availability unit as a primary, backup, or stand-alone unit relies on a self-discovery process.
In step 942, unit X searches the network for a backup unit. If the backup unit is detected, as inquired in step 944, unit X connects to the backup unit and initializes as the primary unit in step 946. If, on the other hand, unit X does not detect any other units in the network within a predetermined time, unit X initializes as a stand-alone unit in step 948.
Once the primary and secondary units have been initialized, configuration changes of the primary unit are also transferred to the backup unit in order to keep the two units synchronized. The configuration information is preferably stored in an LDAP database such as the central policy server database 130 or policy agent databases 124, 126.
In step 956, the primary unit is checked to determine whether it is functional. If it is, the primary unit is likewise updated with the configuration change. Otherwise, if the primary unit is not functional, the backup unit takes on the active role and becomes the active unit in step 958. The primary unit may become non-functional and thus, inactive, due failures in the CPU board, the network interface card, or power supply.
In step 960, the backup unit tags the changes to transfer them to the primary once the primary becomes functional. Once the primary unit becomes functional, the primary unit is updated with the tagged changes maintained by the backup unit as is reflected in step 962.
According to one embodiment of the invention, software updates on the primary and backup units are also synchronized so as to update the primary and backup units serially in a single cycle without the need for multiple update cycles. Thus, the network administrator need not duplicate the efforts of updating the backup unit with the same information as the primary unit.
Although the present invention has been described in detail with reference to the preferred embodiments thereof, those skilled in the art will appreciate that various substitutions and modifications can be made to the examples described herein while remaining within the spirit and scope of the invention as defined in the appended claims.
For example, the unified policy management system of