3Com CoreBuilder 9000, User Manual

Page: 339 / 468

Hierarchy in an E-IISP Network 339
Auto-Discovery After each switch in the hierarchic network has received and registered its
own hierarchic ATM address network prefix, the switch discovers who its
neighbors are and updates its routing table to include its neighbors
information. This process is called
autodiscovery . The autodiscovery
function ensures that the neighboring switches get this information. Each
CoreBuilder 9000 ATM Enterprise Switch periodically transmits a SET
command containing its network prefix to each connection via the ILMI
channel (0,16). Each of its neighboring CoreBuilder 9000 ATM Enterprise
Switches receives the message and stores the received network prefix
together with the port number on which the message was received.
In this way, each CoreBuilder 9000 ATM Enterprise Switch knows the
network prefix of each of its neighbors. For example, in Figure 11, switch
A registers the ATM address prefixes of the three neighbors A1, A2, and
B. Similarly, switch B registers the prefixes of A, B1, and B2.
Auto-Configuration After the switch has “discovered” its neighbor, it configures its interface
protocol to match its neighbor in the lowest common dominator. This
process is called
autoconfiguration . If one switch is configured as IISP
and the other switch is configured as E-IISP, then both switches configure
themselves to IISP.
Static Address
Registration in E-IISP
Static addresses must be registered manually by the LMA. (For more
information, see “Add ATM Address to Port” on page 141).