Network Interfaces; User Network Interface; Network Interface - 3Com CoreBuilder 9000 User Manual

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HAPTER ETWORK

Network Interfaces

User Network
Interface

Network Interface

I M
NTERFACE ANAGEMENT
To enable individual ATM devices to function together in an ATM
network, standard software interfaces are provided between each device
and the devices to which it is connected.
Three types of interfaces are used:


User-Network Interface (UNI) — The interface between an ATM user
device and an ATM switch unit.


Network, Network Interface (NNI) — The interface between two ATM
switch units.


Gateway Interface (GWY) — An IISP interface for connecting the
CoreBuilder 9000 ATM Enterprise Switch to switches of other
®
vendors.
A User-Network Interface (UNI) operates between an ATM user and a
private ATM switch, or between a private ATM switch and the public
carrier ATM network. There is very little difference between a public and a
private UNI. Private UNIs support physical-layer interfaces for
short-distance links, and public UNIs support interfaces between a user
and a carrier that require longer distance performance and carrier
management.
A Network-to-Network Interface (NNI) operates between two ATM
network devices (switches). Each switch may be a private ATM switch or
the public carrier ATM network.