Dynamic routing on networks

Abstract

Systems and methods are provided for routing packets on a network based on information of a routing gateway or a neighboring gateway. One embodiment includes updating a routing table using interface information shared by a neighboring router. Another embodiment includes making routing decisions based on interface information from a neighboring router. Another embodiment includes making routing decisions based on priorities determined from interface information. Another embodiment updating a routing table on a first gateway by receiving data disclosing interface information on a neighboring second gateway and updating a routing table based on the interface information. Another embodiment includes maintaining a routing table on the first gateway that includes, for each route, information on the gateway that is two physical hops away from the first gateway. For each route, if the gateway that is two physical hops away from the first gateway is the first gateway, the route is made inactive.

I claim:  
     
         1 . A gateway for routing over a network, comprising: 
 a transceiver that is configured to receive a signal, wherein the signal includes information that is associated a second gateway that is two physical hops away from the gateway; and    a processor that is configured to perform actions, the actions comprising: 
 maintaining a routing table that identifies a third gateway that is two physical hops away from the gateway; and  
 updating the routing table in response to the signal.  
   
     
     
         2 . The gateway of  claim 1 , wherein the signal includes at least one of a distance vector response message and a link state advertisement message.  
     
     
         3 . The gateway of  claim 1 , wherein the signal is sent from a fourth gateway, the signal includes an entry that indicates an address of the second gateway, and wherein the second gateway is one physical hop away from the fourth gateway.  
     
     
         4 . The gateway of  claim 1 , wherein the signal is sent from a fourth gateway, the signal includes a first indicator that indicates a link type of a link that is associated with the fourth gateway, the second gateway is the third gateway, and wherein if the link type corresponds to a virtual link type, the signal further includes a second indicator that identifies the third gateway.  
     
     
         5 . The gateway of  claim 1 , wherein the gateway is further configured to route packets based on the routing table.  
     
     
         6 . The gateway of  claim 1 , wherein the gateway is further configured to dynamically route packets based on the routing table, and wherein the gateway is part of a one-legged virtual private network.  
     
     
         7 . The gateway of  claim 1 , wherein the routing table includes a plurality of route entries, and wherein the processor is configured to maintain the routing table by including a next_nexthop indicator for each of the plurality of route entries.  
     
     
         8 . The gateway of  claim 7 , wherein the processor is configured to perform further actions, comprising: 
 determining, for each of the route entries, if the next_nexthop indicator identifies the gateway; and    if the next_nexthop indictor identifies the gateway, making the route entry inactive.    
     
     
         9 . A gateway for routing over a network, comprising: 
 a transceiver that is configured to process packets; and    a processor that is configured to perform actions, the actions comprising: 
 maintaining a routing table that includes a plurality of route entries, wherein each of the route entries is associated with a route, each of the route entries includes a next_nexthop indicator, and wherein each next_nexthop indicator identifies another gateway that is two physical hops from the gateway on the associated route; and  
 for each route of the plurality of route entries: 
 determining if the next_nexthop indicator of the route entry identifies the gateway; and  
 if the next_nexthop indicator of the route entry identifies the gateway, making the route inactive.  
 
   
     
     
         10 . The gateway of  claim 9 , wherein the processor is configured to perform further actions, comprising 
 receiving a routing message; and    updating the routing table in response to the routing message.    
     
     
         11 . The gateway of  claim 10 , wherein the routing message is related to one of the next_nexthop indicators, and wherein the processor is configured to update the routing table such that the one of the next_nexthop indicators is updated.  
     
     
         12 . The gateway of  claim 10 , wherein the processor is configured to update the routing table such that a new next_nexthop indicator is added to the routing table.  
     
     
         13 . A method for routing over a network, comprising: 
 maintaining a routing table that is associated with a gateway, wherein the routing table identifies another gateway that is two physical hops away from the gateway, wherein at least one of the two physical hops is associated with a virtual interface; and    routing a packet based upon the routing table.    
     
     
         14 . The method of  claim 13 , wherein the routing table includes a plurality of route entries, each of the route entries includes a next_nexthop indicator, and wherein each next_nexthop indicator identifies an indicated gateway that is two physical hops from the gateway on a route that is associated with the route entry.  
     
     
         15 . The method of  claim 14 , further comprising: 
 for each route of the plurality of routes: 
 determining if the next_nexthop indicator identifies the gateway, wherein the routing table is maintained in the gateway; and  
 if the next_nexthop indicator identifies the gateway, making the route inactive.  
   
     
     
         16 . The method of  claim 13 , further comprising: 
 receiving a signal, wherein the signal includes information that is associated with a second gateway that is two physical hops away the gateway; and    updating the routing table in response to the signal.    
     
     
         17 . The gateway of  claim 16 , wherein the signal is sent from a third gateway, and wherein the signal includes an entry that indicates an address of the second gateway.  
     
     
         18 . A computer-readable medium encoded with a data structure for routing a packet over a network, the data structure comprising: 
 a plurality of route entries, wherein each route entry is associated with a route over the network, wherein the plurality of route entries is associated with a gateway, and    wherein each route entry comprises an indicator that identifies an indicated gateway that is two physical hops away from the gateway.    
     
     
         19 . The computer-readable medium of  claim 18 , wherein, for at least one of the route entries, the indicated gateway is the gateway.  
     
     
         20 . A gateway for routing over a network, comprising: 
 means for maintaining a routing table that identifies at least one gateway that is two physical hops away from the gateway, wherein at least one of the two physical hops is associated with a virtual interface; and    means for routing a packet based upon the routing table.