Apparatus for message filtering in a network using domain class

• US 5,644,571 A
• Filed: 06/04/1993
• Issued: 07/01/1997
• Est. Priority Date: 06/15/1992
• Status: Expired due to Term

• Current Assignee: Enterasys Networks Incorporated (Extreme Networks, Inc.)
• Original Assignee: Digital Equipment Corporation (HP Inc.)
• Inventors: Seaman, Michael J.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): HOM, SHICK C
• Application Number:
  US08/073,217
• Time in Patent Office: 1,488 Days
• Field of Search: 370/85.13, 370/85.14, 370/85.12, 370/85.1, 370/85.4, 370/85.6, 370/112, 370/60, 370/94.1, 370/60.1, 370/62
• US Class Current: 370/401
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge

Abstract

In an apparatus in a computer network, message filtering proceeds by generating respective class specifiers from a received message, using the message source field, message destination field, and type of message field. The class specifiers are used for generating a class specification, and a domain class is generated from the class specification. A domain list is generated to provide a list of ports to which a message directed to the domain class is to be forwarded. The message is forwarded to the ports listed in the domain list. The apparatus may be a bridge, router, etc.

Claims

1. In an apparatus in an area network, message filtering means to direct a received message to at least one port for transmission there-through comprising:

means for generating respective class specifiers for said received message from a contents of a message source field, a message destination field, and a type of message field;

means for generating a class specification from the class specifiers;

means for generating a domain class from the class specification, said domain class having fewer entries than said class specifiers;

means for generating a domain list from the domain class, said domain list having more entries than said domain class, said domain list representing a subarea in the area network to which a message is to be sent; and

means for generating a list of ports from the domain list, said list of ports selected to have said message transmitted there-through.

2. Message filtering means according to claim 1 wherein each of the generating means is provided by respective look-up means.

3. Message filtering means according to either claim 1 or claim 2 wherein the means for generating a class specification from the class specifiers, and the means for generating a domain class from the class specification, comprises a single look-up table.

4. Message filtering means according to either claim 1 or claim 2 wherein the means for generating a class specification from the class specifiers includes concatenating means.

5. Message filtering means according to claim 1 or claim 2 wherein the means for generating a class specification from the class specifiers comprises algorithmic logical combination means.

6. Message filtering means according to claim 1 or claim 2 further comprising dynamic filtering means, the dynamic filtering means output combined with the list of ports.

7. Message filtering means according to claim 3 wherein the means for generating a class specification from the class specifiers includes concatenating means.

8. Message filtering means according to claim 3 wherein the means for generating a class specification from the class specifiers comprises algorithmic logical combination means.

9. Message filtering means according to claim 3 further comprising dynamic filtering means, the dynamic filtering means output combined with the list of ports.

10. Message filtering means according to claim 4 further comprising dynamic filtering means, the dynamic filtering means output combined with the list of ports.

11. Message filtering means according to claim 5 further comprising dynamic filtering means, the dynamic filtering means output combined with the list of ports.

12. In an apparatus in an area network, a method of filtering messages comprising the steps of:

generating respective class specifiers from a message source field, a message destination field, and a type of message field;

generating a class specification from the class specifiers;

generating a domain class from the specification, said domain class having fewer entries than said class specifiers;

generating a domain list from the domain class, said domain list having more entries than said domain class, said domain list representing a subarea of the area network to which a message is to be sent; and

generating a list of ports from the domain list, said list of ports selected to have said message transmitted there-through.