Device and method for forwarding multicast traffic in a hybrid device

• US 20070058646A1
• Filed: 08/25/2005
• Published: 03/15/2007
• Est. Priority Date: 08/25/2005
• Status: Abandoned Application

• Current Assignee: Nokia Siemens Networks GmbH & Company KG (Nokia Corporation)
• Original Assignee: Siemens AG
• Inventors: Hermoni, Roi
• Application Number:
  US11/212,013
• Publication Number:
  US 20070058646A1
• Time in Patent Office: Days
• US Class Current: 370/401
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 12/1886 with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 45/123 Evaluation of link metrics techniques for monitoring network metrics H04L43/08
• CPC Class Codes: H04L 45/16 Multipoint routing

Abstract

A hybrid device for forwarding traffic in a communication network is provided. According to one embodiment, the hybrid device comprises a layer-2 switch, a multicast forwarding information and a multicast router. The layer-2switch forwards a unicast traffic based on a destination address in the data-link layer within the unicast traffic. The multicast forwarding information may be learned by a subscribe request, an unsubscribe request, and query responses. The multicast router forwards a multicast traffic using a network address within a layer-3 header in the multicast traffic and the multicast forwarding information, the multicast traffic is forwarded toward a user device having requested the traffic via a subscribe request.

Claims

1. A hybrid device for forwarding traffic in a communication network, comprising:

a layer-2 switch forwards a unicast traffic, the forwarding based on a destination address in the data-link layer within the unicast traffic;

a multicast forwarding information learned by a subscribe request and an unsubscribe request; and

a multicast router that forwards a multicast traffic using a network address within a layer-3 header in the multicast traffic and the multicast forwarding information, the multicast traffic is forwarded toward a user device having requested the traffic via a subscribe request.

2. The hybrid device according to claim 1, wherein the multicast traffic is forwarded toward a plurality of user devices having requested the traffic via a subscribe request.

3. The hybrid device according to claim 1, wherein the multicast forwarding information is updated on a query response.

4. The hybrid device according to claim 1, wherein the multicast traffic is recognized based on a subnet in the network address.

5. The hybrid device according to claim 1, wherein layer-3 unicast traffic is discarded.

6. The hybrid device according to claim 1, wherein a Reverse Path Flow check is done on the multicast traffic.

7. The hybrid device according to claim 1, wherein the destination address is a Media Access Control (MAC) address.

8. The hybrid device according to claim 1, wherein the network address is a Internet Protocol IP) address

9. A hybrid device for forwarding traffic in a communication network, comprising:

a layer-2 switch that forwards a unicast traffic received from a layer-3 network, the forwarding based on a destination address in the Media Access Control (MAC) within the unicast traffic;

a table having multicast forwarding information learned by a Internet Group Management Protocol (IGMP) requests and responses;

a maximum link cost subnet to recognize a multicast traffic; and

a multicast router that forwards the multicast traffic having an Internet Protocol (IP) address having the maximum link cost subnet and the table, the multicast traffic received from the layer-3 network.

10. The hybrid device according to claim 9, wherein a Reverse Path Flow check is done on the multicast traffic.

11. The hybrid device according to claim 9, wherein the traffic is discarded if received from a downstream link.

12. A method for forwarding a traffic of information by a communication network hybrid device, comprising:

receiving by a network hybrid device a subscribe request from a user device;

updating a table for a multicast router based on the subscribe request;

propagating the request to a layer-3 router in a layer-3 network;

receiving from the layer-3 router a unicast traffic having a Media Access Control (MAC) address and forwarding the unicast traffic based on the MAC; and

receiving from the layer-3 router a multicast traffic having an Internet Protocol (IP) address and forwarding toward the user device the multicast traffic based on the IP address and the table.

13. The method according to claim 12, wherein the IP address has a subnet associated to a maximum link cost

14. The method according to claim 12, wherein prior to forwarding the multicast traffic a Reverse Path Check (RPC) is done and if the multicast traffic is forwarded when the RPC indicates that the received multicast traffic was from an upstream link.

15. The method according to claim 12, further comprising:

receiving a request to unsubscribe from a subscriber and updating the table, and propagating the request to a layer-3 router in a layer-3 network.