Granted Patent B2

US 9,590,996 · App. 11/614,773 · Granted Mar 7, 2017

Abstract

Claims (44)

1. A method for discovering a mobile host that roams across wireless networks, each wireless network comprising a mobile router and the mobile routers being coupled to a gateway, the method comprising:

receiving over one of the wireless networks a packet from the mobile host, the packet including a source address and a destination address;

determining whether the source address resides within a subnet of hosts manageable by the mobile router of the one wireless network;

determining whether the destination address resolves to be within a remote subnet reachable by the gateway;

when both the source address resides within the subnet of hosts manageable by the mobile router of the one wireless network, and the destination address resolves to be within a remote subnet reachable by the gateway, determining whether the source address is within a table of registered mobile hosts; and

when both the source address resides within the subnet of hosts manageable by the mobile router of the one wireless network and the destination address resolves to be within a remote subnet reachable by the gateway, and the source address is not within the table of registered mobile hosts, adding the source address to the table of registered mobile hosts.

2. The method of claim 1 , the table of registered mobile hosts being located in a mobile router.

3. The method of claim 1 , further comprising:

setting a configuration setting to a maximum threshold of time-lapse after traffic is encountered;

monitoring a packet timestamp;

unregistering the mobile host from a gateway table when a time-lapse exceeds the maximum threshold after monitoring the packet timestamp; and

deleting a mobile host entry from the table of registered hosts.

4. The method of claim 1 , further comprising:

when the source address does not reside within the subnet of hosts manageable by the mobile router of the one wireless network, receiving a negative acknowledgment.

5. The method of claim 4 , further comprising:

preventing sending any packets to the mobile host; and

preventing sending any broadcast packets.

6. The method of claim 1 , the packet comprising an address resolution protocol (ARP) broadcast packet from the mobile host.

7. The method of claim 6 , further comprising:

registering the mobile host with a gateway.

8. The method of claim 7 , the registering being requested from a first router and occurring after the gateway deregisters a second mobile host requested from a second router.

9. A non-transitory computer readable medium comprising a program for discovering a mobile host that roams across wireless networks, the medium comprising:

a packet receiving code segment for receiving a packet from the mobile host, the packet including a source address and a destination address;

a source address determining code segment for determining whether the source address resides within a subnet of hosts manageable by the mobile router of the one wireless network;

a destination address determining code segment for determining whether the destination address resolves to be within a remote subnet reachable by the gateway;

a table entry determining code segment for determining whether the source address is within a table of registered mobile hosts when both the source address resides within a subnet of hosts manageable by the mobile router of the one wireless network, and the destination address resolves to be within a remote subnet reachable by the gateway; and

a table entry adding code segment for adding the source address to the table of registered mobile hosts when both the source address resides within a subnet of hosts manageable by the mobile router of the one wireless network and the destination address resolves to be within a remote subnet reachable by the gateway, and the source address is not within the table of registered hosts.

10. The non-transitory computer readable medium of claim 9 , further comprising:

a negative acknowledgment code segment for causing a negative acknowledgment to be sent when the source address is not within the permissible address range.

11. The non-transitory computer readable medium of claim 10 , the negative acknowledgment code segment comprising:

a packet-send-prevent code segment for preventing sending any packets to the mobile host; and

a broadcast-prevent code segment for preventing sending any broadcast packets.

12. The non-transitory computer readable medium of claim 9 , further comprising:

a lease request receiving code segment for receiving a dynamic host configuration protocol (DHCP) lease request from the mobile host.

13. The non-transitory computer readable medium of claim 12 , further comprising:

an address forwarding code segment for causing a DHCP address to be forwarded to the mobile host; and

a registering code segment for causing the mobile host to be registered with a gateway.

14. The non-transitory computer readable medium of claim 9 , further comprising:

a broadcast receiving code segment for receiving an address resolution protocol (ARP) broadcast packet from the mobile host.

15. The non-transitory computer readable medium of claim 14 , further comprising:

a registering code segment for causing the mobile host to be registered with a gateway.

16. The non-transitory computer readable medium of claim 15 , the registering code segment further comprising:

a deregistration request receiving code segment for receiving a deregistration request from the gateway; and

a deregistration code segment for deleting of the source address from a second table of registered hosts.

Assignments (12)