HUT Comms. Lab, Timo O. Korhonen
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nNodes and links with well defined (standardized) interfaces
nNetwork nodes and links that are optimized for certain, assumed traffic
nTraditional assumption: Voice and  data services in different networks
Data and voice networks
Text Box: Divided networks
Divided networks
Frame relay:
- virtual circuits
- used to connect two LANs
- compromises in error
  correction & flow control
- for high quality links
- rates: 2-50 Mb/s
Frame Flow Control:
- service for a pair of
  communicating entities - reassures non-over-
   whelming comms. (not
   too many packets)