3.6 Real-Time Network Routing

Real-Time Network Routing (RTNR) is the successor to DNHR and was deployed in the AT&T long-distance network.

Real-Time Network Routing (RTNR) is an adaptive routing scheme. The routing table for alternate routes can be updated almost on a per call basis.

Consider an RTNR network with N nodes.

	When a call arrives at node i and is destined for node j at time t, node i queries node j seeking information about the status of outgoing links from node j to a switching node k other than node i, i.e., the status of link j-k.
	Because a path is limited to a maximum of two links and circuit-switched links being bidirectional, node i can then determine the status of all two-link paths i-k-j to destination j by combining information for link i-k and link j-k.
	Now, knowing this information, i can decide on choosing an alternate route for this call.

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing

3.6 Real-Time Network Routing