90
C
HAPTER
4: P
RIVATE
N
ETWORK
-
TO
-N
ETWORK
I
NTERFACE
(PNNI) V
ERSION
1.0
The signal between nodes A.2.3 and A.2.2 has failed. A.2.3 will send a
PTSE message that will be flooded to all nodes in the network. At the
same time, it will crankback the signal to the source, so that an alternate
route can be chosen. Figure 29 shows the crankback path.
Figure 29
Crankback Path Back to the Source
In Figure 29, the signal cranked back 6 hops. These hops are decreased
from the hop counter. Node A.1.1 will choose a new path and update its
topology database.
The new topology database information is transmitted as a PTSE message
as described previously. After the topology databases are updated, an
alternate route is chosen. Figure 30 shows the path that node A.1.1 has
chosen after crankback. The alternate route is established and the data is
sent.
X
X
A.1.1
A.1.2
A.1.3
A.1.4
A.1.5
A.1.6
A.1.7
A.1.8
A.1.9
A.2.0
A.2.1
A.2.2
A.2.3
A.2.4
A.2.5
A.2.6
A.2.7
Source
Destination
Place Where Link Failed
Chosen Path to Take
Physical Link
Crankback Path
Summary of Contents for CoreBuilder 7000
Page 12: ......
Page 30: ...30 CHAPTER 1 ATM NETWORK BASICS...
Page 32: ...32 CHAPTER 1 ATM NETWORK BASICS...
Page 34: ...34 CHAPTER 1 ATM NETWORK BASICS Figure 8 LANE Network over WAN...
Page 96: ...96 CHAPTER 4 PRIVATE NETWORK TO NETWORK INTERFACE PNNI VERSION 1 0...
Page 184: ...184 CHAPTER 7 LAN EMULATION VERSIONS 1 0 AND 2 0...
Page 206: ...206 CHAPTER 9 DEVICE MANAGEMENT...
Page 222: ...222 APPENDIX A TECHNICAL SUPPORT...
Page 234: ...234 APPENDIX B PROTOCOLS AND INTERFACES...
Page 238: ...238 APPENDIX C COREBUILDER 7000 FAMILY ATM SWITCH SPECIFICATIONS...
Page 242: ...242 APPENDIX D SAFETY INFORMATION...