Data link layer switch with multicast capability

• US 20050232272A1
• Filed: 06/15/2005
• Published: 10/20/2005
• Est. Priority Date: 04/14/1999
• Status: Active Grant

• Current Assignee: Verizon Laboratories Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Laboratories Incorporated (Verizon Communications Inc.)
• Inventors: Deng, Shuang
• Granted Patent: US 7,573,874 B2
• Time in Patent Office: Days
• US Class Current: 370/390
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 2101/622 Layer-2 addresses, e.g. medium access control [MAC] addresses
• CPC Class Codes: H04L 49/201 Multicast operation; Broadcast operation
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming

Abstract

A data link layer switch includes a switching mechanism coupled to a plurality of port interface controllers. Each of the port interface controllers comprises a multicast address table, a multicast matcher, and a timer. The multicast address table stores multicast addresses for hosts attached to the port interface controller. The multicast matcher matches an incoming packet to a target pattern, generates a multicast address from the incoming packet if the incoming packet matches the target pattern, and stores the generated multicast address in the multicast address table. The timer determines an amount of time that the generated multicast address remains in the multicast address table.

Claims

1-38. -38. (canceled)

39. A system comprising:

a receiver that receives a data packet having a data link layer host address;

a first address table that stores multicast addresses;

a multicast matcher that determines a multicast address from the data packet if the data packet matches a target pattern associated with multicast packets, and stores the determined multicast address in the first address table when at least a portion of the data packet matches the target pattern;

a timing facility that indicates a time at which the determined multicast address is to be removed from the first address table.

41. The system of claim 39, wherein the timing facility includes a counting mechanism.

42. The system of claim 39, further comprising:

a switching mechanism that forwards the data packet to a destination of the data packet.

43. The system of claim 39, wherein the data packet is an Ethernet packet.

44. The system of claim 39, wherein the target pattern is a bit pattern that indicates a multicast packet.

45. The system of claim 39, wherein the multicast matcher is further configured to determine if the data packet is a request to join a multicast group.

46. The system of claim 39, further comprising:

a data link layer address learner that determines the data link layer host address and stores the data link layer host address in a second address table.

47. The system of claim 46, wherein the first address table and the second address table are separate tables.

48. A system comprising:

a receiver that is configured to receive a data packet having a data link layer host address;

a switching mechanism that is configured to forward the data packet;

a multicast address table that stores multicast addresses;

a multicast matcher coupled to the receiver, the switching mechanism and the multicast address table, the multicast matcher configured to receive the data packet from the receiver, determine a multicast address from the data packet if the data packet matches a target pattern associated with multicast packets, store the determined multicast address in the multicast address table when the data packet matches at least a portion of the target pattern, and forward the data packet to the switching mechanism for delivery to a destination of the data packet.

49. The system of claim 48, wherein the multicast matcher is coupled to the switching mechanism via a controller.

50. The system of claim 48, wherein the data packet is an Ethernet packet.

51. The system of claim 48, further comprising:

a timing facility that indicates a time at which the determined multicast address is to be removed from the multicast address table.

52. A method comprising:

receiving a data packet having a data link layer host address;

comparing the data packet to a target pattern;

determining a multicast address from the data packet when at least a portion of the data packet matches the target pattern;

storing the determined multicast address in a data link layer address table;

forwarding the data packet towards a destination of the data packet.

53. The method of claim 52, further comprising:

determining that the data packet includes a request to join a multicast group.

54. The method of claim 52 further comprising:

setting a timer that indicates a time at which the determined multicast address is to be removed from the data link layer address table.

55. The method of claim 52, wherein the data packet is an Ethernet packet.

56. A processor-readable media storing instructions configured to cause a processor to perform the method of claim 52 when executed by the processor.