A DLCI of 100 identi?¬?es the VC that connects to Router B. A DLCI of
400 identi?¬?es the VC that connects to Router C. At the other end, a different DLCI number
can be used to identify the VC.
Frame Relay allows you to interconnect your remote sites in a variety of topologies.
Figure 8-23 illustrates these topologies.
Figure 8-23 Frame Relay Topologies
Full-Mesh
Partial-Mesh
Star (Hub-and-Spoke)
Establishing a WAN Connection with Frame Relay 329
Each topology is further described as follows:
?– Partial-mesh topology: Not all sites have direct access to all other sites. Depending
on the traf?¬?c patterns in your network, you might want to have additional PVCs
connect to remote sites that have large data traf?¬?c requirements.
?– Full-mesh topology: All routers have VCs to all other destinations. Full-mesh
topology, although costly, provides direct connections from each site to all other sites
and allows redundancy. When one link goes down, a router can reroute traf?¬?c through
another site. As the number of nodes in this topology increases, a full-mesh topology
can become very expensive. Use the n (n ??“ 1) / 2 formula to calculate the total number
of links that are required to implement a full-mesh topology, where n is the number of
nodes.
Pages:
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490