Delegate gateways and proxy for target hosts in large layer 2 and address resolution with duplicated internet protocol addresses

1. A method in a network component, comprising:

receiving a plurality of Layer 3 addresses and a plurality of Layer 2 addresses for a plurality of hosts in a corresponding network district in a bridged Layer 2 network;

mapping the Layer 3 addresses of the plurality of hosts to a Layer 2 address of the network component;

receiving a second plurality of Layer 2 addresses for a plurality of district boundary bridges (DBBs) in the bridged Layer 2 network and a second plurality of Layer 3 addresses of a second plurality of hosts associated with the Layer 2 addresses of the DBBs;

mapping the Layer 3 addresses of the second hosts to the Layer 2 address of the corresponding DBBs;

receiving an address resolution protocol (ARP) request that references one of the Layer 3 addresses for one of the hosts;

sending an ARP response that comprises the Layer 2 address of the network component and the Layer 3 address of the host but not the Layer 2 address of the host in response to the ARP request; and

not maintaining one or more Layer 3 address and one or more Layer 2 addresses for one or more hosts external of the plurality of hosts,

wherein each DBB is configured to be aware of a plurality of Layer 2 addresses of the DBBs, and not aware of Layer 3 addresses of end-stations within network districts that are external of the network districts associated with the DBB.

2. The method of claim 1 , further comprising:

receiving a plurality of delegate Layer 2 addresses associated with an application in the corresponding network district for a plurality of subnets in the bridged Layer 2 network; and

mapping the delegate Layer 2 addresses to an Layer 3 address for the application.

3. The method of claim 2 , further comprising:

receiving a frame that comprises a Layer 2 destination address (DA) that references one of the delegate Layer 2 addresses and a Layer 3 DA that references the Layer 3 address for the application; and

sending the frame to the application,

wherein sending the frame to the application comprises translating the delegate Layer 2 DA to a second Layer 2 DA that corresponds to the Layer 3 address for the application that is mapped to the delegate Layer 2 address.

4. The method of claim 1 , further comprising announcing the Layer 2 address of the network component and the Layer 3 addresses of the hosts in the corresponding network district, and wherein the Layer 2 address of the network component and the Layer 3 address of the hosts in the corresponding network district are announced via one or more gratuitous ARP messages.

5. The method of claim 1 , further comprising:

receiving a frame that comprises a Layer 2 destination address (DA) that references the Layer 2 addresses of the DBB and a Layer 3 DA that references the Layer 3 address for one of the hosts; and

sending the frame to the host,

wherein sending the frame to the host comprises translating the Layer 2 DA of the network component to a second Layer 2 DA corresponding to the Layer 3 DA of the host that is mapped to the Layer 2 address of the network component.

6. An apparatus for communicating data traffic, comprising:

a memory; and

a processor couple to the memory, wherein the memory includes instructions that when executed by the processor cause the apparatus to perform the following:

receive an address resolution protocol (ARP) request that comprises a Layer 3 address associated with a first end-station within a network external to the network associated with the apparatus;

send a directory service (DS) query that comprises the Layer 3 address associated with the first end-station;

receive a DS response in response to sending the DS query, wherein the DS response comprises a Layer 2 address, a Layer 3 address, or both for a district boundary bridge (DBB) associated with the Layer 3 address of the first end-station;

send an ARP response that comprises the Layer 2 address, the Layer 3 address, or both for the DBB associated with the Layer 3 address of the first end-station; and

not maintain one or more Layer 3 address and one or more Layer 2 addresses for one or more end-stations external to a local network corresponding with the DBB,

wherein each DBB is configured to be aware of a plurality of Layer 2 addresses of the DBBs, and not aware of Layer 3 addresses of end-stations within network districts that are external of the network districts associated with the DBB.

7. The apparatus of claim 6 , wherein the ARP response further comprises the Layer 3 address of the DBB associated with the first end-station.

8. The apparatus of claim 6 , wherein the instructions, when executed by the processor, cause the apparatus to:

receive a frame that comprises a Layer 2 destination address (DA) that references the DBB and a Layer 3 DA that references the first end-station; and

send the frame to the DBB using the Layer 2 DA that references the DBB.

9. The apparatus of claim 6 , wherein the DS query further comprises a local network label for a second end-station that is located within the local network corresponding with the apparatus.

10. The apparatus of claim 9 , wherein the local network label corresponds to a customer identifier (ID).

11. The apparatus of claim 10 , wherein the Layer 2 address of the DBB is a delegate Layer 2 address that correspond to the customer ID.

12. The apparatus of claim 6 , wherein the computer executable instructions, when executed by the processor, cause the apparatus to send a plurality of Layer 3 addresses for a plurality of second end-stations located within the local network corresponding with the apparatus and the Layer 2 address of the apparatus.