Dynamic access-point link aggregation
An access point that provides link aggregation is described. During operation, this access point receives a message that may include a Dynamic Host Configuration Protocol (DHCP) response with an Internet protocol (IP) address of a gateway for an electronic device to access a network and a media access control (MAC) address of the electronic device. Based on the MAC address and/or at least a characteristic of the electronic device (such as a configuration, a capability and/or an operating system of the electronic device), the access point may determine a different IP address of another gateway for the electronic device to access the network. Moreover, the access point may modify the DHCP response by substituting the IP address of the other gateway for the IP address of gateway in a modified DHCP response. Next, the access point provides the modified DHCP response to the electronic device.
1. An access point, comprising:
an antenna node configured to couple to an antenna; and
an interface circuit, coupled to the antenna node, configured to wirelessly communicate with a second access point in a subnet, wherein the access point is configured to perform operations comprising:
receiving, at the antenna node, Gratuitous Address Resolution Protocol (ARP) packets associated with the second access point;
when the access point subsequently does not receive a Gratuitous APR packet associated with the second access point within a time interval, assuming a second logical address of the second access point, which is in addition to an existing logical address of the access point; and
in response to receiving an ARP request associated with an electronic device that comprises the second logical address of the second access point, providing, to the antenna node, an ARP response intended for the electronic device, wherein the ARP response comprises a physical address of the access point, so that subsequent packets or frames associated with the electronic device are directed to the access point instead of the second access point.
2. The access point of claim 1 , wherein the access point and the second access point are each gateways for the subnet.
3. The access point of claim 1 , wherein the access point is configured to provide preassigned redundancy coverage for the second access point.
4. The access point of claim 1 , wherein the existing logical address of the access point comprises an Internet Protocol (IP) address and the second logical address of the second access point comprises a second IP address; and
wherein the access point is configured to implement IP aliasing.
5. The access point of claim 1 , wherein the physical address of the access point comprises a Media Access Control (MAC) address of the access point.
6. The access point of claim 1 , wherein the physical address of the access point is different from a second physical address of the second access point.
7. The access point of claim 1 , wherein the access point is configured to implement ARP spoofing or proxy ARP.
8. The access point of claim 1 , wherein the operations comprise, after assuming the second logical address of the second access point and prior to receiving the ARP request:
receiving, at the antenna node, a frame or packet associated with the electronic device, wherein the frame or packet comprises a second physical address of the second access point and the second logical address of the second access point; and
providing, to the antenna node, a second frame or packet intended for the electronic device that indicates that the second physical address of the second access point is incorrect.
9. The access point of claim 1 , wherein the operations comprise, after providing the ARP response, receiving, at the antenna node, a frame or packet associated with the electronic device; and
wherein the frame or packet comprises the physical address of the access point and the second logical address of the second access point.
10. The access point of claim 1 , wherein the operations comprise, after providing the ARP response:
receiving, at the antenna node, a second Gratuitous APR packet associated with the second access point; and
in response to the second Gratuitous ARP packet, no longer assuming the second logical address of the second access point.
11. The access point of claim 10 , wherein the operations comprise, after no longer assuming the second logical address of the second access point:
receiving, at the antenna node, a frame or packet associated with the electronic device, wherein the frame or packet comprises the physical address of the access point and the second logical address of the second access point; and
providing, to the antenna node, a second frame or packet intended for the electronic device that indicates that the physical address of the access point is incorrect.
12. The access point of claim 10 , wherein the operations comprise, after no longer assuming the second logical address of the second access point, provide, to the antenna node, a third Gratuitous ARP packet to the subnet, which indicates that the physical address of the access point is incorrect for the second logical address of the second access point.
13. A non-transitory computer-readable storage medium for use in conjunction with an access point, the computer-readable storage medium storing program instructions that, when executed by the access point, cause the access point to provide preassigned redundancy coverage for a second access point by performing operations comprising:
receiving Gratuitous Address Resolution Protocol (ARP) packets associated with the second access point;
when the access point subsequently does not receive a Gratuitous APR packet associated with the second access point within a time interval, assuming a second logical address of the second access point, which is in addition to an existing logical address of the access point; and
in response to receiving an ARP request associated with an electronic device that comprises the second logical address of the second access point, providing an ARP response intended for the electronic device, wherein the ARP response comprises a physical address of the access point, so that subsequent packets or frames associated with the electronic device are directed to the access point instead of the second access point.
14. The non-transitory computer-readable storage medium of claim 13 , wherein the existing logical address of the access point comprises an Internet Protocol (IP) address and the second logical address of the second access point comprises a second IP address; and
wherein the access point is configured to implement IP aliasing.
15. The non-transitory computer-readable storage medium of claim 13 , wherein the physical address of the access point comprises a Media Access Control (MAC) address of the access point.
16. The non-transitory computer-readable storage medium of claim 13 , wherein the operations comprise, after assuming the second logical address of the second access point and prior to receiving the ARP request:
receiving a frame or packet associated with the electronic device, wherein the frame or packet comprises a second physical address of the second access point and the second logical address of the second access point; and
providing a second frame or packet intended for the electronic device that indicates that the second physical address of the second access point is incorrect.
17. The non-transitory computer-readable storage medium of claim 13 , wherein the operations comprise, after providing the ARP response:
receiving a second Gratuitous APR packet associated with the second access point; and
in response to the second Gratuitous ARP packet, no longer assuming the second logical address of the second access point.
18. A method for provide preassigned redundancy coverage for a second access point, comprising:
by an access point:
receiving Gratuitous Address Resolution Protocol (ARP) packets associated with the second access point;
when the access point subsequently does not receive a Gratuitous APR packet associated with the second access point within a time interval, assuming a second logical address of the second access point, which is in addition to an existing logical address of the access point; and
in response to receiving an ARP request associated with an electronic device that comprises the second logical address of the second access point, providing an ARP response intended for the electronic device, wherein the ARP response comprises a physical address of the access point, so that subsequent packets or frames associated with the electronic device are directed to the access point instead of the second access point.
19. The method of claim 18 , wherein the existing logical address of the access point comprises an Internet Protocol (IP) address and the second logical address of the second access point comprises a second IP address; and
wherein the access point is configured to implement IP aliasing.
20. The method of claim 18 , wherein the method comprises, after assuming the second logical address of the second access point and prior to receiving the ARP request:
receiving a frame or packet associated with the electronic device, wherein the frame or packet comprises a second physical address of the second access point and the second logical address of the second access point; and
providing a second frame or packet intended for the electronic device that indicates that the second physical address of the second access point is incorrect.