Private Network; (Pnni) V Ersion; Introducing Pnni Version - 3Com CoreBuilder 7000 Operation Manual

4
Introducing PNNI
Version 1.0
P N
RIVATE
I
NTERFACE
This chapter provides basic concepts and information about:

Introducing PNNI Version 1.0

PNNI vs. E-IISP


PNNI Routing


Configuring the PNNI Network


PNNI Signaling Protocol
PNNI is available in version 4.5 extended only.
PNNI (Private Network to Network Interface) is a new dynamic routing
and signaling protocol designed for ATM networks, which ensures stable,
reliable voice, video, and data transfer over the ATM network. Since it is a
network to network interface, PNNI is only used between switches. For
information on the interface protocol used between switches and
workstations, as well as LAN to ATM devices, see "User Network
Interface" on page 36 in the Management Guide. PNNI is dynamic as it
enables the establishment of a call specifically catered to the needs of the
session (data, voice or video). It knows in advance the QoS (Quality of
Service) needed for each type of connection and will use this information
to find the best path to establish the connection.
PNNI uses a routing algorithm based on the OSPF (Open Shortest Path
First) protocol, which is a Link-State Routing technology with additions. In
the PNNI network, each ATM switch passes its local topology information
to all its neighbors (like E-IISP), but this information is also propagated to
all switches in the locally advertised ATM network. All routing information
is stored in a topology database, which the node builds and modifies as it
learns more information about its environment. In the ATM network, the
topology database contains reachability and QoS metrics and attributes
information. Reachability information is a list of reachable addresses for
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(PNNI) V
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ETWORK
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ERSION