Cabletron Systems 04-0053-01 User Manual

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3-8   SmartSwitch ATM User Guide
Multi-level PNNI Topology
  PNNI Routing
2.
Add a third node (at level 64) to either switch SWA3 or SWB3. 
3.
Use the 
set pnnipglelection
 command to designate the switch’s second node (not third) as the 
PGL for the parent peer group, and specify the third node as the parent node of the second. 
4.
Perform steps 2 and 3 for switches with the same role in the other level 72 parent groups.
These steps create a grandparent group at level 64, and establishes a virtual link between the LGNs that represent the 
LGNs at level 72 (see Figure 3-3).
Figure 3-3 Adding a third PNNI node for next level connectivity
PGL
PGL
PGL
PGL
PGL
PGL
Level 80
Level 72
Level 64
First nodes
Second node
Third node
Virtual Link
Virtual Link
Virtual Link
SWA3
SWA3
SWA3
SWB3
LGN
LGN
Parent Groups
Grandparent Group
Lowest Peer Groups