Typical Deployment Scenarios
Typical deployment scenarios for Carrier Ethernet services using bridged networks
include, from the most general to the most narrow:
?– Ethernet backbone services
?– Sparse wide area business services
?– Metro area business services
?– ISP access services
Given the techniques presented in this chapter, all of these scenarios play together, can
be interconnected, and can cooperate with each other, even across provider-to-provider
connections.
Ethernet Backbone Services
Ethernet services can be offered at the largest scale using the network depicted in
Figure 13.1. One can imagine a national network of such EVCs, with the routers that
provide the IP connectivity using these EVCs, instead of being directly connected. This
backbone service does not itself provide universal connectivity! Ethernet??™s flat address
space, if nothing else, makes that fundamentally impractical. This backbone service is
not equivalent to an enterprise network, where a VLAN can spread anywhere in the
network at the whim of the users and lead to gross inefficiencies in packet distribution.
It is more like a national-scale patch panel for interconnecting the routers that provide
universal connectivity and for providing EVCs to customers.
Pages:
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934