United States Patent  [n] Patent Number: 5,347,633
Ashfield et al.  Date of Patent: Sep. 13, 1994
1988, New York, N.Y., US pp. 8-17 W. S. Lai: "Packet Forwarding".
Computer Networking Symposium, Nov. 1986, Washington, D.C., US, pp. 189-195 P. A. Ligomenides et al.: "Local Rerouting in Computer Communication Networks".
Primary Examiner—Parshotam S. Lall
Assistant Examiner—Ayni Mohamed
Attorney, Agent, or Firm—Gerald R. Woods
An enhanced intervention list is used in a data communication network used to route messages from a source or originating user to a destination user in the network. The enhanced intervention list includes an intervention type field which defines how an intercepted distribution is to be processed. For an Associative Redirection intervention type, the message is redirected to a destination user identified in the intervention list. For a Predirecting Intervention type, the message is diverted to an intervening agent or program identified in the intervention list. After the message is processed by the intervening agent, it is routed to a user directory which identifies the destination node serving the destination user. For a Postdirecting Intervention type, the message is sent to the local user directory first and is then checked against the intervention list entries to see if intervention is still warranted. The enhancements to the intervention list provide greater flexibility in handling of intercepted messages.
5 Claims, 9 Drawing Sheets
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