Because Layer 2 scalability depends entirely upon Layer 3 routing, the throughput of traditional
backbone routers is today's network bottleneck.
Initially, routing switches aggregate risers and connect to the
backbone router. This offloads local IP traffic (source and destination within the building) from congested routers and improves performance between building subnets.
3 shows that the PIT size for the randomly selected gateway router or
backbone router increases dramatically when suffering MDA, which means MDA can severely damage NDN routers by exhausting their memory resources.
1 into [M.sub.K] (where k=0, 1, 2) three level networks such that the cost of a given multicast group is the weighted sum of each of the three level network cost plus the extra overhead of linking each three level network to the IP
backbone router. In this respect, a given multicast group size, S can be restrictedly partitioned into [M.sub.0], [M.sub.1], and [M.sub.2] such that [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII.] (where
Third, by putting functionality like QoS in a
backbone router, flexibility and scalability are sacrificed in applying QoS policies, meaning a less adaptable solution to address the diversity and growth happening at the edge of the network.
Based on Foundry's customer proven IronCore ASIC designs, the NetIron 1500 is a high density carrier class Internet
backbone router which offers customers the ability to deploy a full spectrum of broadband wide area network interfaces ranging from OC-192c/STM-64, OC-48c/STM-16, OC-12c/STM-4, OC-3c/STM-1, ATM to DS3.
Multiple LAN segments are bridged within a
backbone router to create virtual LANs (VLANs).