<<Even an ATM switch "fabric" is statiscal in nature.>>
No - not statistical - deterministic - this makes testing, configuration, provisioning, managing,... much easier.
<<If all traffic in an ATM switch comes in, destined for the same output port, for too long a period of time, cells are dropped >>
Yes, cells can be dropped, but only according to the customer's service contract. If a customer buys N Gbits/sec, they get a max of N Gbits/sec no matter what the load on the network. If the customer does not have the load at a particular instant, then packets from other customers with a different contractual arrangement (ABR - available bit rate - for less $$), can be carried.
If a customer exceeds their contractual bit rate, then these extra packets are subject to being tossed away if another contract needs the bandwidth.
Just like airline seats can be sold at different prices to match market needs, ATM packet bandwidth can be sold at different prices. Adjacent packets in a pipe can bring in substantially different revenue, just like adjacent passengers can have different prices on their ticket stubs. |
