Method and device for managing multicast groups

• US 7,908,354 B2
• Filed: 11/12/2009
• Issued: 03/15/2011
• Est. Priority Date: 06/26/2007
• Status: Expired due to Fees

• Current Assignee: Media Patents S.L.
• Original Assignee: Media Patents S.L.
• Inventors: Fernandez Gutierrez, Alvaro
• Primary Examiner(s): Lin, Kenny S
• Application Number:
  US12/617,711
• Publication Number:
  US 20100054249A1
• Time in Patent Office: 488 Days
• Field of Search: 709/223, 709/220
• US Class Current: 709/223
• CPC Class Codes: H04L 12/185 with management of multicast group membership

Abstract

A method for managing multicast traffic in a data network, and devices using said method. The hosts store for each multicast group an included source record and an excluded source record, and the network interfaces of the hosts send to the router a message containing information about the included source record and information about the excluded source record. The router also stores for each multicast group an included source record and an excluded source record, and updates them when it receives through its network interface a message from the hosts containing information about an included source list and/or information about an excluded source list. The devices are a router, host equipment and network equipment compatible with the method.

Claims

1. A process implemented in a multicast router having one or more downstream network interfaces and situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the multicast router storing for a downstream network interface and a multicast group address at least an INCLUDE record having an include source list containing a source or set of sources derived by data requests made by the one or more hosts and an EXCLUDE record having a requested list containing a source or set of sources and an exclude list containing a source or set of sources derived by data requests made by the one or more hosts, the process comprising modifying the INCLUDE record upon receiving a MODE_IS_INCLUDE type message from a host without modifying the EXCLUDE record.

2. A method for updating a state transition table of a multicast router in communication with one or more multicast group addresses and having one or more downstream network interfaces, the transition table storing for a particular downstream network interface and a particular multicast group address an INCLUDE record having an include source list containing a source or set of sources A and an EXCLUDE record having a requested list containing a source or set of sources X and an exclude list containing a source or set of sources Y, the method comprising:

receiving through the particular downstream network interface a MODE_IS_INCLUDE message having an include source list containing a source or set of sources B of the multicast group address and;

changing the INCLUDE record source list to contain the union of the sources or sets of sources A and B (A+B) without modifying the EXCLUDE record.

3. A process implemented in a multicast router having one or more downstream network interfaces and situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the multicast router storing for a downstream network interface and a multicast group address at least an INCLUDE record having an include source list containing a source or set of sources derived by data requests made by the one or more hosts and an EXCLUDE record having a requested list containing a source or set of sources and an exclude list containing a source or set of sources derived by data requests made by the one or more hosts, the process comprising modifying the EXCLUDE source record upon receiving a MODE_IS_INCLUDE type message from a host without modifying the INCLUDE record.

4. A method for updating a state transition table of a multicast router that receives multicast packets from one or more multicast group addresses and having one or more downstream network interfaces, the state transition table storing for a particular downstream network interface and a particular multicast group address an INCLUDE record having an include source list containing a source or set of sources A and an EXCLUDE record having a requested list containing a source or set of sources X and an exclude list containing a source or set of sources Y, the method comprising:

receiving through the particular downstream network interface a MODE_IS_EXCLUDE message having an exclude source list containing a source or set of sources B of the multicast group address and;

changing the EXCLUDE record source list to have a requested list containing the set of sources B minus the sources of B that are also in the set of sources Y (B−

Y) and an exclude list containing the intersection of the sets of sources Y and B (Y*B) without modifying the INCLUDE record.

5. A method for updating a state transition table of a multicast router that receives multicast packets from one or more multicast group addresses and having one or more downstream network interfaces, the state transition table storing for a particular downstream network interface and a particular multicast group address an INCLUDE record having an include source list containing a source or set of sources A and an EXCLUDE record having a requested list containing a source or set of sources X and an exclude list containing a source or set of sources Y, the method comprising:

receiving through the particular downstream network interface an ALLOW message containing a source or set of sources B of the multicast group address and;

changing the INCLUDE record source list to contain the union of the sources or sets of sources A and B (A+B) without modifying the EXCLUDE record.

6. A method for updating a state transition table of a multicast router that receives multicast packets from one or more multicast group addresses and having one or more downstream network interfaces, the state transition table storing for a particular downstream network interface and a particular multicast group address an INCLUDE record having an include source list containing a source or set of sources A and an EXCLUDE record having a requested list containing a source or set of sources X and an exclude list containing a source or set of sources Y, the method comprising:

receiving through the particular downstream network interface an ALLOW type message containing a source or set of sources B of the multicast group address and;

changing the INCLUDE record source list to contain the union of the sources or sets of sources A and B (A+B) without modifying the EXCLUDE record.

7. A method for updating a state transition table of a multicast router that receives multicast packets from one or more multicast group addresses and having one or more downstream network interfaces, the state transition table storing for a particular downstream network interface and a particular multicast group address an INCLUDE record having an include source list containing a source or set of sources A and an EXCLUDE record having a requested list containing a source or set of sources X and an exclude list containing a source or set of sources Y, the method comprising:

receiving through the particular downstream network interface an ALLOW type message containing a source or set of sources B of the multicast group address and;

changing the EXCLUDE record source list to have a requested list containing the union of the set of sources X and B (X+B) and an exclude list containing the set of sources Y minus the set of sources Y that are also in the set of sources B (Y−

B) without modifying the INCLUDE record.

8. A method for maintaining a state transition table of a multicast router that receives multicast packets from one or more multicast group addresses and having one or more downstream network interfaces, the state transition table storing for a particular downstream network interface and a particular multicast group address an INCLUDE record having an include source list containing a source or set of sources A and an EXCLUDE record having a requested list containing a source or set of sources X and an exclude list containing a source or set of sources Y, the method comprising:

receiving through the particular downstream network interface a BLOCK type message containing a source or set of sources B of the multicast group address and in response not modifying the INCLUDE or the EXCLUDE record.

9. A method for updating a state transition table of a multicast router that receives multicast packets from one or more multicast group addresses and having one or more downstream network interfaces, the state transition table storing for a particular downstream network interface and a particular multicast group address an INCLUDE record having an include source list containing a source or set of sources A and an EXCLUDE record having a requested list containing a source or set of sources X and an exclude list containing a source or set of sources Y, the method comprising:

receiving through the particular downstream network interface an BLOCK type message containing a source or set of sources B of the multicast group address and;

changing the EXCLUDE record source list to have a requested list containing the union of the set of sources X and the set of sources B minus the set of B sources that are also in the set of sources Y (X+(B−

Y)) and an exclude list containing the set of sources Y without modifying the INCLUDE record.