System and Method to Support Enhanced Equal Cost Multi-Path and Link Aggregation Group

• US 20110164503A1
• Filed: 06/09/2010
• Published: 07/07/2011
• Est. Priority Date: 01/05/2010
• Status: Active Grant

• Current Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Peilin, Yang, Yong, Lucy
• Granted Patent: US 8,619,587 B2
• Time in Patent Office: Days
• US Class Current: 370/237
• CPC Class Codes: H04L 69/14 Multichannel or multilink protocols
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

An apparatus comprising a small flow forwarding module configured to distribute and forward a plurality of packets that correspond to a plurality of small flows over a plurality of paths, a large flow forwarding module configured to distribute and forward a plurality of packets that correspond to a plurality of large flows over the paths, and a packet header checking module in communication with the small flow forwarding module and the large flow forwarding module, wherein the packet header checking module is configured to inspect a flow indication in an incoming packet and forward the packet to the small flow forwarding module if the flow indication corresponds to one of the small flows or to the large flow forwarding module if the flow indication corresponds to one of the large flows.

Claims

1. An apparatus comprising:

a small flow forwarding module configured to distribute and forward a plurality of packets that correspond to a plurality of small flows over a plurality of paths;

a large flow forwarding module configured to distribute and forward a plurality of packets that correspond to a plurality of large flows over the paths; and

a packet header checking module in communication with the small flow forwarding module and the large flow forwarding module, wherein the packet header checking module is configured to inspect a flow indication in an incoming packet and forward the packet to the small flow forwarding module if the flow indication corresponds to one of the small flows or to the large flow forwarding module if the flow indication corresponds to one of the large flows.

2. The apparatus of claim 1, wherein the large flows have a plurality of first transmission rates and the small flows have a plurality of second transmission rates, and wherein the first transmission rates are substantially larger than the second transmission rates.

3. The apparatus of claim 1, wherein the incoming packet is a pseudowire (PW) packet and the flow indication is a flow label that comprise a traffic class (TC) and a time to live (TTL) field.

4. The apparatus of claim 3, wherein the flow indication corresponds to a small flow if a bit of the TC is set to about zero, and wherein the flow indication corresponds to a large flow if the bit is set to about one.

5. The apparatus of claim 3, wherein the TTL field comprises a value equal to about zero to indicate that a bottom label of the packet is the flow label.

6. The apparatus of claim 1, wherein the incoming packet is a Label Switched Path (LSP) packet and a bottom label of the packet is an entropy label.

7. The apparatus of claim 1, wherein the incoming packet is an Internet Protocol (IP) version 6 packet that comprises a flow label with a large flow classification in an IP header, wherein the flow indication corresponds to a large flow if a bit in a traffic class (TC) field is set to about one.

8. The apparatus of claim 1, wherein the incoming packet is an Internet Protocol (IP) version 4 packet that comprises a flow label with a large flow classification in an IP header, wherein the flow indication corresponds to a large flow if a bit in a type of service field is set to about one.

9. A network component comprising:

a large flow forwarding and congestion control module coupled to a plurality of aggregated paths and configured to distribute and forward a plurality of packets that correspond to a plurality of large flows over the aggregated paths and substantially maintain load balance over the aggregated paths,

wherein the large flow forwarding and congestion control module stops forwarding a large flow that is assigned to a path in the aggregated paths if the path becomes substantially congested, and discards or caches the large flow packets or redirects the large flow to a second path.

10. The network component of claim 9, wherein the flow assigned to the congested path is discarded or redirected to a second path in the aggregated paths.

11. The network component of claim 9, wherein the flow assigned to the congested path is temporarily cached and then forwarded when congestion in the aggregated paths is resolved.

12. The network component of claim 9, wherein the large flow is selected based on its Quality of Service (QoS) requirement.

13. A network component comprising:

at least one processor coupled to a memory and configured to;

detect a large flow indication in a received packet;

forward the packet to one of a plurality of aggregated paths based on a first flow forwarding algorithm if the large flow indication indicates that the packet does not correspond to a small flow; and

forward the packet to one of the paths based on a second flow forwarding algorithm if the large flow indication indicates that the packet corresponds to a large flow.

14. The network component of claim 13, wherein the first forwarding algorithm is an equal cost multi-path (ECMP) algorithm or a Link Aggregation Group (LAG) forwarding algorithm that uses hashing to assign the small flow to one of the aggregated paths.

15. The network component of claim 13, wherein the second forwarding algorithm uses a flow forwarding table to assign the large flow to one of the aggregated paths.

16. The network component of claim 15, wherein the processor is further configured to:

check each entry in the flow forwarding table for an active status value;

replace the active status value with an aging status value if the active status value is found in any entry; and

remove the entry from the flow forwarding table if the aging status value is found in any entry.

17. The network component of claim 15, wherein the processor is further configured to:

obtain a flow identifier (ID) in the packet;

determine if there is an entry for the flow ID is the flow forwarding table;

add to the flow forwarding table a new entry that comprises the flow ID, a path ID that corresponds to one of the aggregated paths assigned to the large flow, and an active status value if the flow ID is not found in the flow forwarding table; and

update the active status value in the entry for the flow ID if the flow ID is found in the flow forwarding table.

18. A method comprising:

receiving a packet that corresponds to a flow at an edge node in a network;

configuring a large flow indication in the packet to indicate that the flow is a large flow or a small flow; and

forwarding the packet to an internal node in the network.

19. The method of claim 18 further comprises:

determining if there is an entry for the flow in a large flow table;

configuring the flow indication in the packet to indicate that the flow is a large flow if an entry for the flow is found in the large flow table; and

adding an entry for the flow to the large flow table if there is no entry for the flow in the large flow table and if the flow is determined to be a large flow.

20. The method of claim 18 further comprises temporarily caching the packets if the flow is determined to be a large flow to guarantee forwarding the packet in proper sequence when the flow is distributed and transported over a plurality of paths.