User-friendly interface for setting expressions on an SNMP agent

• US 6,085,237 A
• Filed: 05/01/1998
• Issued: 07/04/2000
• Est. Priority Date: 05/01/1998
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Durham, Sandra, Kavasseri, Ramanathan
• Primary Examiner(s): Meky, Moustafa M.
• Application Number:
  US09/071,821
• Time in Patent Office: 795 Days
• Field of Search: 709/200, 709/201, 709/202, 709/206, 709/220, 709/221, 709/222, 709/223, 709/224
• US Class Current: 709/221
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/046 comprising network management agents or mobile agents therefor

Abstract

Network communication between a management station and an expression management information base (MIB) on a simple network management protocol (SNMP) agent entails complex analysis and configuration during creation of the variables. In order to alleviate this concern, an interface is provided which accepts an expression from a user, parses the expression to determine if it is in proper form, creates SNMP set packets to set the expression on the expression MIB and sends the SNMP set packets to the expression MIB of the SNMP agent. Alternatively, a similar interface may be located within the SNMP agent or node, and requires no communication over the network in order to evaluate expressions.

Claims

1. A method for defining an expression on an SNMP agent having expression MIB including the steps of:

accepting the expression from a user;

parsing said expression to determining if it is in proper form for an expression;

creating SNMP set packets to set said expression on the expression MIB; and

sending said SNMP set packets to the expression MIB of the SNMP agent.

2. The method of claim 1, wherein said creating step includes the step of:

forming an expression SNMP set packet and assigning it said expression.

3. The method of claim 2, wherein said creating step further includes the step of:

forming an expression name status SNMP set packet and assigning it the value for create and wait.

4. The method of claim 2, wherein said creating step further includes the step of:

forming an expression name SNMP set packet and assigning it the expression'"'"'s name.

5. The method of claim 4, further including the step of:

prompting the user for the expression'"'"'s name.

6. The method of claim 2, wherein said creating step further includes the step of:

forming an expression value type SNMP set packet and assigning it the type of the value of the expression.

7. The method of claim 6, further including the step of:

prompting the user for the type of the value of the expression.

8. The method of claim 2, wherein said creating step further includes the step of:

forming an expression owner SNMP set packet and assigning it the entity that configured the expression.

9. The method of claim 2, wherein said creating step further includes the step of:

for each variable to be formed, forming a object status SNMP set packet and assigning it the value for create and wait, forming an object identifier SNMP set packet and assigning it the identification of the variable and forming an expression object identification wildcard SNMP set packet and setting it to true if said object identifier SNMP set packet is not fully qualified.

10. The method of claim 2, wherein said creating step further includes the step of:

forming an expression object status SNMP set packet and assigning it the value for active.

11. The method of claim 2, wherein said creating step further includes the step of:

forming an expression name status SNMP set packet and assigning it the value for active.

12. The method of claim 1, further including the steps of:

documenting said expression, its intended purpose, and how it should be used.

13. The method of claim 1, further including the step of:

saving said expression in a file for later use.

14. The method of claim 1, further including the step of:

determining if said expression is badly formed and generating error reports if it is so that the user may correct errors.

15. The method of claim 14, wherein said determining step includes the step of:

determining if said expression is syntactically correct and generating error reports if it is not so that the user has a chance to correct errors.

16. The method of claim 14, wherein said determining step includes the step of:

determining if said expression is semantically correct and generating error reports if it is not so that the user has a chance to correct errors.

17. The method of claim 1, further including the steps of:

finding out the types of all the object identifiers and sub-expressions within said expression; and

verifying that the types of the object identifiers and the sub-expressions logically fit the type of the result of said expression.

18. The method of claim 17, wherein said finding out step includes the step of:

finding out the types of all the object identifiers and sub-expressions within said expression by implicit inference using knowledge built into the interface.

19. The method of claim 17, wherein said finding out step includes the step of:

finding out the types of all the object identifiers and sub-expressions within said expression by accepting input from the user.

20. The method of claim 17, wherein said verifying step includes the step of:

verifying that the types of the object identifiers and the sub-expressions logically fit the type of the result of said expression, as defined by the expression MIB of the SNMP agent.

21. The method of claim 1, further including the step of:

initiating evaluation of the expression on said agent.

22. The method of claim 1, further including the step of:

retrieving and translating the results of said evaluation.

23. An interface for defining an expression on an SNMP agent or node having an expression MIB including:

an input block which accepts the expression from a user;

a parser which parses said expression to determine if it is in the proper form for an expression;

a creator which creates SNMP set packets to set said expression on the expression MIB; and

a sender which sends said SNMP set packets to the expression MIB of the SNMP agent.

24. The interface of claim 23, wherein said creator includes:

a set packet former which forms an expression SNMP set packet and assigns it said expression.

25. The interface of claim 23, wherein said creator includes:

a set packet former which forms an expression name status SNMP set packet and assigns it the value for create and wait.

26. The interface of claim 23, wherein said creator includes:

a set packet former which forms an expression name SNMP set packet and assigns it the expression'"'"'s name.

27. The interface of claim 26, further including:

a prompter which prompts the user for the expression'"'"'s name.

28. The interface of claim 23, wherein said creator further includes:

a set packet former which forms an expression value type SNMP set packet and assigns it the type of the value of the expression.

29. The interface of claim 28, further including:

a prompter which prompts the user for the type of the value of the expression.

30. The interface of claim 23, wherein said creator further includes:

a set packet former which forms an expression owner SNMP set packet and assigns it the entity that configured the expression.

31. The interface of claim 23, wherein said creator further includes:

a set packet former which, for each variable to be formed, forms a object status SNMP set packet and assigns it the value for create and wait, forms an object identifier SNMP set packet and assigns it the identification of the variable and forms an expression object identification wildcard SNMP set packet and sets it to true if said object identifier SNMP set packet is not fully qualified.

32. The interface of claim 23, wherein said creator further includes:

a set packet former which forms an expression object status SNMP set packet and assigns it the value for active.

33. The interface of claim 23, wherein said creator further includes:

a set packet former which forms an expression name status SNMP set packet and assigns it the value for active.

34. The interface of claim 23, further including a memory module which documents each expression, its intended purpose, and how it should be used.

35. The interface of claim 23, further including a memory module which saves expressions in a file for later use.

36. The interface of claim 23, further including an expression checker which determines if said expression is badly formed and generates error reports if it is so that the user may correct errors.

37. The interface of claim 23, wherein said expression checker further includes a syntax checker which determines if said expression is syntactically correct and generates error reports if it is not so that the user may correct errors.

38. The interface of claim 23, wherein said expression checker further includes a semantic checker which determines if said expression is semantically correct and generates error reports if it is not so that the user may correct errors.

39. The interface of claim 23, further including:

a type finder which finds out the types of all the object identifiers and sub-expressions within said expression; and

a type checker which verifies that the types of the object identifiers and the sub-expressions logically fit the type of the result of said expression.

40. The interface of claim 39, wherein said type finder uses implicit inference using knowledge built into the interface to find out all the object identifiers and sub-expressions within said expression.

41. The interface of claim 39, wherein said type finder accepts input from the user to find out the types of all the object identifiers and sub-expressions within said expression.

42. The interface of claim 39, wherein said type checker verifies that the types of the object identifiers and the sub-expressions logically fit the type of the result of said expression, as defined by the expression MIB.

43. The interface of claim 23, further including an evaluation initiator which initiates evaluation of the expression on said agent.

44. The interface of claim 23, further including a retriever/translator which retrieves and translates the results of said evaluation.