>>The Edge is the last mile..Isn't it..??? <<
Angela, not quite, or should I say, not usually. Let me attempt to clarify the last mile versus the edge, where Telco wireline services are concerned. I'm sure Mark will jump in if I am off base.
user--> residential network--> last mile--> access--> edge--> core--> [and reverse]
The "last mile" is comprised of:
-- feeder plant - the large cables emanating directly from the central office;
-- distribution plant - smaller cables that branch out from the feeder, to discrete neighborhood poles or green service pedestals; and,
-- drop cables - the last couple hundred feet of cable that extends from the pole or pedestal into your window, or to the side of the house.
[Note: Feeder and distribution definitions are reversed for cable TV outside plant.]
Then there are the access platforms, which reside between the last mile and the edge. These access devices could be central office based DSL access multiplexers, switches, dialup concentrators, etc.
Access platforms feed the edge network. In the case of IP, these are routers or frame relay devices, which, in turn, feed the core network.
The core could be made up of hierarchically more-significant routers, or frame relay nodes, or ATM switches. On the other side of the core, the entire process reverses.
The above is a plain vanilla depiction of a standard network architectural scheme. Note that excessive distances from the central office often warrant loop extension techniques, such as subscriber line carrier systems and field concentration units. And sometimes the access components and the edge components can be extended, as well, sometimes through virtual means, to suit both the user's needs and the criteria of the network architecture.
HTH, and Regards, Frank Coluccio |
