
ForeRunner
ATM Switch Network Configuration Manual
5 - 3
Fore
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ght PNNI
ForeThought PNNI
5.1.4 Hierarchical Routing
FT-PNNI operates in a hierarchical topology. The structure of the hierarchy is defined by the
peer group ID in a routing domain. Address assignment in FT-PNNI, therefore, corresponds to
this hierarchical topology, providing increased scalability.
Figure 5.1 -
Example of a 13-byte Switch Prefix
5.1.4.1 Hierarchical Addressing
FT-PNNI uses private ATM address prefixes (NSAP prefixes) as node identifiers. FT-PNNI
does not distinguish between node identifiers and reachability information. Thus, the IDs of
nodes in the FT-PNNI addressing map are NSAP prefixes. In the default case at the lowest
level peer group, the switches have a 13-byte prefix as their node ID and end systems (hosts)
have a 19-byte prefix as their node ID.
5.1.4.1.1
Switch Prefix
Each switch in a FT-PNNI network is configured with a 13-byte prefix called the switch prefix.
Hosts that are attached to the switch are presented with this prefix during ILMI address regis-
tration. In this way, end systems are configured with a private ATM address that includes the
13-byte switch prefix.
104 bits
Switch Prefix
Switch Summary Prefix
Peer Group ID
Summary of Contents for forerunner series
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Page 16: ...TOC 10 ForeRunner ATM Switch Network Configuration Manual Table of Contents ...
Page 20: ...LOF 4 ForeRunner ATM Switch Network Configuration Manual List of Figures ...
Page 22: ...LOT 2 ForeRunner ATM Switch Network Configuration Manual List of Tables ...
Page 30: ...viii ForeRunner ATM Switch Network Configuration Manual Preface ...
Page 144: ...3 58 ForeRunner ATM Switch Network Configuration Manual Configuring an Emulated LAN ...
Page 180: ...6 12 ForeRunner ATM Switch Network Configuration Manual ATM Forum PNNI ...
Page 220: ...9 6 ForeRunner ATM Switch Network Configuration Manual Configuring Timing ...
Page 300: ...D 24 ForeRunner ATM Switch Network Configuration Manual Configuring FramePlus Modules ...
Page 308: ...Acronyms 8 ForeRunner ATM Switch Network Configuration Manual Acronyms ...
Page 346: ...Glossary 38 ForeRunner ATM Switch Network Configuration Manual Glossary ...
Page 352: ...Index 6 ForeRunner ATM Switch Network Configuration Manual Index ...