Tag echo discovery protocol to detect reachability of clients

• US 6,694,369 B1
• Filed: 03/30/2000
• Issued: 02/17/2004
• Est. Priority Date: 03/30/2000
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: 3Com Corporation (HP Inc.)
• Inventors: Connery, Glenn, Binder, James, Vepa, RamKrishna
• Primary Examiner(s): Wiley, David
• Assistant Examiner(s): DELGADO, MICHAEL A
• Application Number:
  US09/539,923
• Time in Patent Office: 1,419 Days
• Field of Search: 709/221, 709/228, 709/223, 709/225, 709/220, 370/254, 370/401, 370/466, 370/255, 713/1
• US Class Current: 709/228
• CPC Class Codes: H04L 43/50 Testing arrangements

Abstract

A method for detecting reachability of client computers communicatively coupled in a computer network to a server computer. A plurality of identifier tags are resident in the memory of the server. The server generates a data packet comprising an I.C.M.P. echo packet and selects a first identifier tag from among the plurality of identifier tags resident in memory, the first identifier tag being chosen to correspond to a first client computer. The server inserts the first identifier tag into the proper data segment of the echo packet and forwards the packet to the first client. After a predetermined time awaiting a responsive ping from the client, the server determines if the client is tag-compliant or non tag-compliant.

Claims

1. In a server computer comprising a processor, a memory, said server computer communicatively coupled to a plurality of client computers in a network, a method for detecting reachability of client computers comprising:

storing a first reachability file comprising a plurality of records, wherein each record indicates a status of each “

compliant”

client computer;

storing a second reachability file comprising a plurality of records, wherein each record indicates a status of each “

non-compliant”

client computer

generating a first data packet with an I.C.M.P. packet for a data payload;

selecting a first identifier tag from among a select plurality of identifier tags stored within said first reachability file or said second rechability file;

inserting said first identifier tag into a proper data segment of said first data packet, thereby forming a first tagged ping packet;

transmitting said first tagged ping packet to a first client computer;

determining whether said first client computer is “

compliant”

or “

non-compliant”

from a response to said first tagged ping packet;

moving one of said plurality of records of said first reachability file, corresponding to said first client computer, to said second reachability file if said first client computer is determined to be “

non-compliant”

; and

moving one of said plurality of records of said second reachability file, corresponding to said first client computer, to said first reachability file if said first client computer is determined to be “

compliant”

.

2. The method for detecting reachability of clients according to claim 1, further comprising deriving said first identifier tag from an incoming message prior to inserting said first identifier tag into said first data packet.

3. The method for detecting reachability of clients according to claim 1, further comprising:

receiving a subsequent message containing an incoming identifier tag;

searching said first reachability file for said incoming identifier tag;

determining the status of said incoming identifier tag from said first reachability file;

providing said incoming identifier tag is “

compliant”

, re-transmitting said subsequent message; and

providing incoming identifier tag is “

non-compliant”

, removing said incoming identifier tag from said subsequent message and re-transmitting said subsequent message without an identifier tag.

4. The method for detecting reachability of clients according to claim 1, further comprising:

receiving a subsequent message lacking an identifier tag;

generating an identifier tag from data contained in said subsequent message;

determining the status of said generated identifier tag comparing said generated identifier tag to said select plurality of identifier tags stored within in said first reachability file or said second reachability file;

providing said generated identifier tag is “

compliant”

, inserting said generated identifier tag into said subsequent message and re-transmitting said subsequent message; and

providing said generated identifier tag is “

non-compliant”

, re-transmitting said subsequent message without an identifier tag.

5. The method for detecting reachability of clients according to claim 1, further comprising:

receiving a subsequent message lacking an identifier tag;

inserting a universal identifier tag into a proper data segment of said message; and

re-transmitting said subsequent message.

6. The method for detecting reachability of clients according to claim 1, wherein:

said memory comprises a cache type memory;

said method further comprises;

selecting a first priority record from said select plurality of records in said first reachability file or said second reachability file; and

storing said first priority record in said cache type memory.

7. The method for detecting reachability of clients according to claim 6, wherein said cache type memory is static.

8. The method for detecting reachability of clients according to claim 6, wherein said cache type memory is dynamic, said server computer further comprising a cache management algorithm and a first set of attributes corresponding to said first priority identifier tag in said cache type memory.

9. The method for detecting reachability of clients according to claim 1, wherein said network comprises a heterogeneous mix of “

compliant” and

“

non-compliant”

client computers.

10. The method for detecting reachability of clients according to claim 1, wherein said identifier tag is an 802.1 q/P identifier tag.

11. A networked server system comprising:

a server computer comprising;

a server memory for storing a first and second reachability file each comprising a plurality of records, wherein each record comprises a tag identifier corresponding to one of a plurality of client computers;

a server processor operatively connected to said server memory, for performing a process comprising;

selecting a first identifier tag from among a select plurality of identifier tags stored within said first reachability file or said second rechability file;

inserting said first identifier tag into a proper data segment of said first data packet, thereby forming a first tagged ping packet;

transmitting said first tagged ping packet to a first client computer;

determining whether said first client computer is “

compliant”

or “

non-compliant”

from a response to said first tagged ping packet;

moving one of said plurality of records of said first reachability file, corresponding to said first client computer, to said second reachability file if said first client computer is determined to be “

non-compliant”

;

moving one of said plurality of records of said second reachability file, corresponding to said first client computer, to said first reachability file if said first client computer is determined to be “

compliant”

;

receiving a subsequent message containing an incoming identifier tag;

determining the status of said incoming identifier tag by comparing said incoming identifier tag to a select plurality of identifier tags stored within said first reachability file or said second reachability file;

providing said incoming identifier tag is “

compliant”

, re-transmitting said subsequent message; and

providing said incoming identifier tag is “

non-compliant”

, removing said incoming identifier tag from said subsequent message and re-transmitting said subsequent message without an identifier tag; and

at least one transmission port operatively connected to said server processor; and

said first client computer comprising;

a client processor; and

a client transmission port operatively connected to said client processor; and

a transmission means operatively connecting said at least one transmission port of said server to said transmission port of said client.

12. The server computer system according to claim 11, wherein said processor performs said process further comprises deriving said first identifier tag from an incoming message prior to inserting said first identifier tag into said first data packet.

13. The server computer system according to claim 11, wherein said processor performs said process farther comprising:

receiving a subsequent message lacking an identifier tag;

generating an identifier tag from data contained in said subsequent message;

determining the status of said generated identifier tag by comparing said generated identifier tag to a select plurality of identifier tags stored within said first reachability file or said second reachability file;

providing said generated identifier tag is “

compliant”

, inserting said generated identifier tag into said subsequent message and re-transmitting said subsequent message; and

providing said generated identifier tag is “

non-compliant”

, re-transmitting said subsequent message without an identifier tag.

14. The server computer system according to claim 11, wherein process further comprises:

receiving a subsequent message lacking an identifier tag;

inserting a universal identifier tag into a proper data segment of said subsequent message; and

re-transmitting said subsequent message.

15. The server computer system according to claim 11, wherein:

said server computer further comprises a cache type memory; and

said process further comprises;

selecting a first priority record from said plurality of records; and

storing said first priority record in said cache type memory.

16. The server computer system according to claim 15, wherein said cache type memory further comprises a first set of attributes, said first set of attributes corresponding to said first priority identifier tag.

17. The server computer system according to claim 11, wherein said systems network comprises a heterogeneous mix of “

compliant” and

“

non-compliant”

client computers.

18. The server computer system according to claim 12, wherein said identifier tag is an 802.1 q/P identifier tag.

19. A computer-readable medium containing a plurality of instructions which when executed cause a server computer to implement a method for detecting reachability of a client computer comprising:

generating a first data packet within said server computer, said data packet having an I.C.M.P. packet for a data payload;

selecting a first identifier tag from among a plurality of identifier tags stored in a select one of a first or second reachability file;

inserting a first identifier tag into a proper data segment of said first data packet, thereby forming a first tagged ping packet;

transmitting said first tagged ping packet to a first client computer;

determining an updated status of said first client computer as “

compliant”

or “

non-compliant”

from a response to said first tagged ping packet;

moving one of a plurality of records of said first reachability file, corresponding to said first client computer, to said second reachability file if said first client computer is determined to be “

non-compliant”

;

moving one of a plurality of records of said second reachability file, corresponding to said first client computer, to said first reachability file if said first client computer is determined to be “

non-compliant”

.

20. The computer-readable medium according to claim 19, further comprising deriving said first identifier tag from an incoming message prior to inserting said first identifier tag into said first data packet.

21. The computer-readable medium according to claim 19, further comprising:

receiving a subsequent message containing an incoming identifier tag;

determining the status of said incoming identifier tag by comparing said incoming identifier tag to said select plurality of identifier tags stored within said first reachability file or said second reachability file;

providing said incoming identifier tag is “

compliant”

, re-transmitting said subsequent message; and

providing said incoming identifier tag is “

non-compliant”

, removing said incoming identifier tag from said subsequent message and re-transmitting said subsequent message without an identifier tag.

22. The computer-readable medium according to claim 19, further comprising:

receiving a subsequent message lacking an incoming identifier tag;

generating a generated identifier tag for said subsequent message from data in said subsequent message;

comparing said generated identifier tag to said select plurality of identifier tags stored within said first reachability file or said second reachability file;

determining the status of said generated identifier tag by comparing said generated identifier tag to said select plurality of identifier tags in said first reachability file or said second reachability file;

providing said generated identifier tag is “

compliant”

, inserting said generated identifier tag into said subsequent message and re-transmitting said subsequent message; and

providing said generated identifier tag is “

non-compliant”

, re-transmitting said subsequent message without an identifier tag.

23. The computer-readable medium according to claim 19, further comprising:

receiving a subsequent message lacking an incoming identifier tag;

inserting a universal identifier tag into a proper data segment of said subsequent message; and

re-transmitting said subsequent message.

24. The computer-readable medium according to claim 19, further comprising:

selecting a first priority record from said select plurality of records stored within said first reachability file or said second reachability file; and

storing said first priority record in a cache type memory.

25. The computer-readable medium according to claim 24, said cache type memory is static.

26. The computer-readable medium according to claim 24, wherein said cache type memory is dynamic, and further comprising a cache management algorithm and a first set of attributes corresponding to said first priority identifier tag in said cache type memory.