Method and filter system for filtering messages received via a serial data bus of a communication network by a user of the network

• US 20110125855A1
• Filed: 03/05/2009
• Published: 05/26/2011
• Est. Priority Date: 03/10/2008
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Ihle, Markus, Hartwich, Florian, Bailer, Franz, Horst, Christian
• Granted Patent: US 9,154,324 B2
• Time in Patent Office: Days
• US Class Current: 709/206
• CPC Class Codes: H04L 12/40032 Details regarding a bus interface enhancer
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 2012/40215 Controller Area Network CAN
• CPC Class Codes: H04L 63/0227 Filtering policies mail message filtering H04L51/212

Abstract

A method and a filter system for filtering messages which are received, via a serial data bus of a communications network, in a communication module of a user connected to the data bus. To allow particularly simple and efficient filtering of incoming messages, even when there is a large number of filtering criteria, it is proposed that the filter system includes a list in which multiple identifier pairs are stored which define a range delimited in each case by a first identifier and a second identifier. The identifier for an incoming message is compared at least to selected identifier pairs from the list, and a query is made concerning whether the identifier for the incoming message is greater than, or greater than or equal to, the selected first identifier, and is less than, or less than or equal to, the selected second identifier. The incoming message is forwarded to the application or rejected, depending on the configuration bit specification, if the identifier for the incoming message is within the range delimited by the first identifier and the second identifier.

Claims

1-14. -14. (canceled)

15. A method for filtering messages, which are received, via a serial data bus of a communication network, in a communication module of a user connected to the data bus, the method comprising:

using a filter system, the messages each having an identifier for identification, and the characteristics of the filter system being defined by message identifiers which are stored in at least one list of the filter system;

storing multiple identifier pairs in the at least one list of the filter system which define a range delimited in each case by a first identifier and a second identifier;

comparing the identifier for an incoming message to at least selected identifier pairs;

making a query concerning whether the identifier for the incoming message is greater than or equal to the selected first identifier and less than or equal to the selected second identifier; and

forwarding the incoming message to the application or rejected it if the identifier for the incoming message is within the range delimited by the first identifier and the second identifier.

16. The method of claim 15, wherein the identifier for an incoming message is compared to identifier pairs from the list until the identifier for the incoming message is within the range delimited by the first identifier and the second identifier of the identifier pair in the current query, or until the end of the list is reached.

17. The method of claim 15, wherein the identifier for an incoming message, beginning with a given identifier pair from the list, is compared to an identifier pair in the list immediately following the identifier pair of the preceding query until the identifier for the incoming message is within the range delimited by the first identifier and the second identifier of the identifier pair in the current query, or until the end of the list is reached.

18. The method of claim 15, wherein in addition to each identifier pair, associated filter type information is stored in the list of the filter system, an incoming message being one of forwarded to the application and rejected, depending on the filter type information of the identifier pair in the current query, if the identifier for the incoming message is within the range delimited by the first identifier and the second identifier in the current query.

19. The method of claim 15, wherein in addition to each identifier pair, associated forwarding information is stored in the list of the filter system, and wherein an incoming message is forwarded to a given buffer memory for retrieval by the application, depending on the forwarding information of the identifier pair in the current query, if the identifier for the incoming message is within the range delimited by the first identifier and the second identifier in the current query.

20. The method of claim 15, wherein the filter system has at least one further list containing message identifiers, the identifier for an incoming message being compared at least to selected identifiers from the further list, and a query being made concerning whether the identifier for the incoming message is equal to a selected identifier from the further list, and the incoming message is forwarded to the application or is rejected if the identifier for the incoming message is equal to the selected identifier from the further list.

21. The method of claim 20, wherein the first identifiers and second identifiers of the identifier pairs stored in the at least one list are used as identifiers in the at least one further list, and wherein an incoming message is forwarded to the application or is rejected if the identifier for the incoming message is one of equal to the first identifier and equal to the second identifier of a selected identifier pair.

22. The method of claim 15, wherein the filter system has at least one further list containing at least one of acceptance identifiers and acceptance masks, wherein the identifier for an incoming message is compared at least to at least one of selected acceptance identifiers and to selected acceptance masks from the further list, wherein a query is made concerning whether the identifier for the incoming message is equal to a selected acceptance identifier or is included by the acceptance mask, and wherein the incoming message is forwarded to the application or is rejected if the identifier for the incoming message is equal to the selected acceptance identifier or is included by the acceptance mask.

23. The method of claim 22, wherein the first identifiers and the second identifiers of the identifier pairs stored in the at least one list are used as at least one of acceptance identifiers and acceptance masks of the at least one further list, and wherein an incoming message is forwarded to the application or is rejected if the identifier for the incoming message is equal to the first identifier for a selected identifier pair or is included by the second identifier for the selected identifier pair.

24. A filter system for a communication module of a user which is connected to a serial data bus of a communication network, for filtering incoming messages received via the data bus, the messages each having an identifier for identification, comprising:

a filtering arrangement, including;

at least one list containing identifiers for messages via which the characteristics of the filter system are defined, wherein multiple identifier pairs are stored in the at least one list of the filter system which define a range delimited in each case by a first identifier and a second identifier; and

a query arrangement to compare the identifier for an incoming message at least to selected identifier pairs to determine whether the identifier for the incoming message is greater than or equal to the selected first identifier and is less than or equal to the selected second identifier;

wherein the filter system arrangement causes incoming messages to be forwarded to the application or rejected if the identifier for the incoming message is within the range delimited by the first identifier and the second identifier.

25. The filter system of claim 24, wherein the filter system has a memory element, which is one of a random access memory, a read-only memory, and a nonvolatile memory for storing the identifier pairs of the list.

26. The filter system of claim 25, wherein the memory element has a width of 32 bits.

27. The filter system of claim 24, wherein the filter system includes separate lists for standard 11-bit identifiers for CAN messages and for extended 29-bit identifiers for CAN messages.

28. The filter system of claim 24, wherein the filter system includes separate lists for CAN data frame messages and for CAN remote frame messages.