3Com CoreBuilder 7000 Operation Manual page 78

78 C 4: P
HAPTER RIVATE
N - -N I
ETWORK TO ETWORK NTERFACE
Table 19 shows the list of information node A.1.2 collects from its
neighbors after the hello protocols are sent.
Table 19 Topology Database for Node A.1.2
Node ID
A.1.2
A.1.3
A.2.1
A.3.1
The learning does not stop here. After the hello message has been
broadcasted, the nodes in the network scan the information they have
collected. Each node analyzes the information it receives and notes which
nodes are within its peer group. Using Figure 19 as an example, node
A.1.2 marks node A.1.3 as a member of its group. Once all hello packets
are synthesized, the information that is common to the node's peer group
is put together into a new packet of information called a PTSE - PNNI
Topology State Element.
PTSE
PTSE is the smallest collection of PNNI routing information that is flooded
as a unit over all links within a peer group to reach all nodes in the peer
group. In this message the nodes relay all of the information that they
have collected that matches their peer group number. This information is
used to build the topology database for the node. Figure 20 shows the
PTSE exchange.
A.1.1
A.1.3
Figure 20 Passing PTSE Messages
(PNNI) V 1.0
ERSION
Description
Myself
My neighbor
A node in Group A.2
A node in Group A.3
Peer Group A.1
At this stage PTSE messages are
passed to all nodes in the
A.1.2
peer group.