Configuring Les Le_Arp Policies - 3Com CoreBuilder 7000 Operation Manual

destination in its FDB ARP-cache. The way the LES handles LE_ARP
requests can be configured by management (see "Configuring LES
LE_ARP Policies" on page 151).
On receipt of the destination LEC address, the transmitting LEC
Data-direct VCC
establishes a data-direct VCC for direct communication across the ATM
network to the destination LEC if one does not already exist.
In a similar way, the LEC uses address resolution during initialization to
VCC to BUS
ascertain the ATM address of the BUS. Once known, the multicast-send
and multicast-forward VCCs are established between LEC and BUS and
any unknown unicast, multicast or broadcast messages are sent on it.
Configuring LES The way in which the LES handles LE_ARP requests from a LEC can be
LE_ARP Policies configured by management. Each LES in the CoreBuilder switch can be
configured independently. Three such policies can be set:






LE_ARP Response Policy
The LE_ARP response policy determines whether or not the LES searches
for the LAN destination in the LE_ARP request in its own data base. There
are two policies as shown in Table 39:
.
Table 39 LE_ARP Response Policies
ELAN Response Policy
The ELAN response policy pertains to the possible recipients of a response
of a LES to an LE_ARP request by a LEC. Two policies are possible as
shown in Table 40:
LE_ARP Response Policy
ELAN Response Policy
LE_ARP Response Policy for Route Descriptors
Policy Description
Respond Checks the address table of the LES in the CoreBuilder 7000. If
the LAN destination is not found, it sends the LE_ARP request to
all LECs in the ELAN. If the LAN destination is found, it sends the
LE_ARP response to recipients selected according to the ELAN
response policy.
Forward Request Does not check the address table of the LES in the CoreBuilder
7000 but instead immediately sends the LE_ARP request to all
LECs in the ELAN.
LAN Emulation in the CoreBuilder 7000 151