Point-to-multipoint virtual circuits for metropolitan area networks

• US 20020038253A1
• Filed: 03/01/2001
• Published: 03/28/2002
• Est. Priority Date: 03/02/2000
• Status: Abandoned Application

• Current Assignee: Qwest Communications International Incorporated (Lumen Technologies, Inc.)
• Original Assignee: Qwest Communications International Incorporated (Lumen Technologies, Inc.)
• Inventors: Klessig, Robert W., Jain, Vipin, Jaszewski, Gary, Seaman, Michael J.
• Application Number:
  US09/796,922
• Publication Number:
  US 20020038253A1
• Time in Patent Office: Days
• US Class Current: 705/26
• CPC Class Codes: G06Q 30/02 Marketing; Price estimation or determination; Fundraising
• CPC Class Codes: G06Q 30/0601 Electronic shopping [e-shopping]

Abstract

A point to multipoint communication channel in a metropolitan area network among a plurality of demarcation points having unique addresses is provided, which includes identifying a particular demarcation point as a root of the channel, and a plurality of client demarcation points as leaves of the channel; and configuring so that client demarcation points can only exchange packets with the root demarcation point, and not with other client demarcation points; and so that the root demarcation point can exchange packets with the plurality of client demarcation points. The channel is managed using source address filtering at switches on the leaves of the channel and a switch at the root of the channel.

Claims

1. A method of providing a point to multipoint communication channel in a metropolitan area network among a plurality of demarcation points having unique addresses, comprising:

identifying a particular demarcation point in the network as a root of the channel, and a plurality of client demarcation points in the network as leaves of the channel; and

configuring switches in the network so that

client demarcation points can only exchange packets on the network with the particular demarcation point, and not with other client demarcation points; and

so that

the particular demarcation point can exchange packets on the network with the plurality of client demarcation points.

2. The method of claim 1, wherein a switch attached to a respective client demarcation point in the plurality of client demarcation points is configured to recognize addresses of the particular demarcation point and of the respective client demarcation point, to forward onto the network packets received on ports coupled to the respective client demarcation points carrying source addresses equal to the address of the respective client demarcation point and a destination address which is one of a multicast address, a broadcast address and the address of the particular demarcation point, to forward onto a port coupled to the respective demarcation points packets received on ports coupled to the network carrying the source addresses of the particular demarcation point, and destination addresses equal to one of a multicast address, a broadcast address and the address of the respective client demarcation point, and to discard other packets.

3. The method of claim 1, wherein a switch coupled to the particular demarcation point identified as the root is configured to the recognize the address of the particular demarcation point and addresses of the plurality of client demarcation points, to forward on a port coupled to the network packets received on a port coupled to the particular demarcation point carrying the source address of the particular demarcation point and one of a multicast address, a broadcast address and the address of one of the plurality of client demarcation points, and to discard other packets, to forward on a port coupled to the particular demarcation point packets received on a port coupled to the network carrying the source address of one of the plurality of client demarcation points and a destination address equal to one of a multicast address, a broadcast address and the address of the particular demarcation point, and to discard other packets.

4. The method of claim 1, wherein said configuring includes allocating the particular demarcation point identified as the root and the plurality of client demarcation points a virtual LAN identifier.

5. The method of claim 1, wherein the switches execute a communication protocol for a switched LAN with multicast capability.

6. The method of claim 1, wherein the switches execute a protocol compliant with an Ethernet standard.

7. The method of claim 1, wherein the network includes a service interface unit, the service interface unit having a service interface coupled via a link to a customer device having an unique MAC address, and having a network interface coupled via a link to one of said switches, and wherein said demarcation points comprise service interfaces on service interface units.

8. The method of claim 1, wherein the switches execute a layer two protocol for routing traffic among said demarcation points.

9. The method of claim 1, including:

organizing switches according to a network architecture and placing security functions within that architecture;

assuring a unique identity for each device connected to a service interface anywhere within the network; and

checking said identities at points identified within the network architecture.

10. The method of claim 9, wherein said network architecture includes a switched network managed according to a spanning tree protocol.

11. The method of claim 9, wherein said network architecture includes a switched network managed according to a spanning tree protocol, and wherein the architecture includes a plurality of switches organized in to access switches and interior switches, the access switches coupled to service interface units acting as demarcation points and the interior switches interconnecting the access switches, and wherein said security functions are places in the access switches, and wherein said unique identity is provided by MAC addresses of devices coupled to the service interface units.

13. The network of claim 12, wherein an access switch attached to a respective client demarcation point in the plurality of client demarcation points is configured to recognize addresses of the particular demarcation point and of the respective client demarcation point, to forward onto the network packets received on ports coupled to the respective client demarcation points carrying source addresses equal to the address of the respective client demarcation point and a destination address which is one of a multicast address, a broadcast address and the address of the particular demarcation point, to forward onto a port coupled to the respective demarcation points packets received on ports coupled to the network carrying the source addresses of the particular demarcation point, and destination addresses equal to one of a multicast address, a broadcast address and the address of the respective client demarcation point, and to discard other packets.

14. The network of claim 12, wherein an access switch coupled to the particular demarcation point identified as the root is configured to the recognize the address of the particular demarcation point and addresses of the plurality of client demarcation points, to forward on a port coupled to the network packets received on a port coupled to the particular demarcation point carrying the source address of the particular demarcation point and one of a multicast address, a broadcast address and the address of one of the plurality of client demarcation points, and to discard other packets, to forward on a port coupled to the particular demarcation point packets received on a port coupled to the network carrying the source address of one of the plurality of client demarcation points and a destination address equal to one of a multicast address, a broadcast address and the address of the particular demarcation point, and to discard other packets.

15. The network of claim 12, wherein the plurality of switches execute a communication protocol for a switched LAN with multicast capability.

16. The network of claim 12, wherein the plurality of switches execute a protocol compliant with an Ethernet standard.

17. The network of claim 12, wherein the network includes a service interface unit, the service interface unit having a service interface coupled via a link to a customer device having an unique MAC address, and having a network interface coupled via a link to one of said access switches, and wherein said demarcation points comprise service interfaces on service interface units.

18. The network of claim 12, wherein the plurality of switches execute a layer two protocol for routing traffic among said demarcation points.

19. The network of claim 12, wherein the plurality of switches are configured to execute a spanning tree protocol.

12. A metropolitan area network including a point-to-multipoint channel, comprising:

a plurality of communication links which traverse a metropolitan area;

a plurality of switches coupled to the communication links, the switches including access switches and interior switches; and

a plurality of demarcation points coupled to access switches in the plurality of switches, the demarcation points comprising service interfaces to the network having unique addresses;

wherein the plurality of access switches are configured to identify a particular demarcation point in the plurality of demarcation points as a root of the channel, and a plurality of client demarcation points in the plurality of demarcation points as leaves of the channel, and so that

client demarcation points can only exchange packets on the network with the particular demarcation point, and not with other client demarcation points; and

so that

the particular demarcation point can exchange packets on the network with the plurality of client demarcation points.