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ForeRunner ATM Switch Network Configuration Manual
ATM Forum PNNI
6.2 PNNI Signalling Protocol
PNNI signalling is used to establish point-to-point and point-to-multipoint connections across
the network. This protocol is based on ATM Forum UNI signalling with mechanisms added to
support source routing and crankback.
6.2.1 Source Routing
A DTL is a source route which specifies the preferred call routing path that the ForeThought
PNNI or PNNI router should use when setting up an SVC. Each DTL is a source route and
each entry in the DTL represents a single hop in that source route. Each hop is represented by
a ForeThought PNNI or PNNI node and the logical output port at that node.
6.2.2
Crankback
During PNNI signalling, a call being processed according to a DTL may encounter a blocked
node or link along the designated route. Crankback allows a partial reroute of such a rejected
call so that it does not have to be cleared the whole way back to the source. Additionally, an
indication of the blockage and subsequent reroute information is sent to the originator of the
DTL.
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 ...