This setup requires configuring the LE clients with the correct ELAN Name.
vUse names for the LE clients
Each LE client can be given its own name. For example, you could create the
policy values (Joe, LES_A) and (Mary, LES_A).Then, the LE clients configured
with these names would be directed to the same LES. This method requires
configuring the ELAN name at each LE client and at the LECS. However, it
allows Joe and Mary to move the client to a new location. Even though moving
causes the client to have a new ATMaddress or MAC address, as long as you
configure the new LE client with the same ELAN name, you retain membership in
the original ELAN. This technique also offers a moderate amount of security if the
names of each LE client are considered to be passwords.

ELAN Type Policy

ELAN type policy values are most useful for providing default ELANs. For example,
the following policy values would ensure that every LE client is assigned to one of
the LESs:
(Token-ring ELAN Type, LES_A)
(Ethernet ELAN Type, LES_B)
(Unspecified ELAN Type, LES_C)
In general, policies used for providing default ELAN assignments should be given a
low priority, so that the more specific policies are considered first.

Max Frame Size Policy

The max frame size policy can also be used to provide default ELAN assignments.

Duplicate Policy Values

Duplicates occur when the same policy value is associated with multiple LESs for a
given policy. Duplicate policy values are allowed for the ELAN type and max frame
size policies, but are not allowed for other policies. Duplicate values are useful only
when combined with a different policy of the same priority.
For example, assume that there are three ELANs: an Ethernet ELAN with a max
frame size of 4544 bytes, a Token-RingELAN with a max frame size of 4544 bytes,
and another Token-RingELAN with a max frame size of 18190 bytes. LE clients
could be assigned to the appropriate ELAN by setting the ELAN type and max
frame size policies to the same priority level and defining the following policy
values:
(Ethernet ELAN Type, LES_1) (Max Frame Size = 4544, LES_1)
(Token-Ring ELAN Type, LES_2) (Max Frame Size = 4544, LES_2)
(Token-Ring ELAN Type, LES_2) (Max Frame Size = 18190, LES_2)
More Information About TLVs
TLVs are defined on an ELAN basis; therefore, the same set ofTLVs is returned to
all LE clients that are assigned to a particular ELAN. When a TLVis included in a
configuration response, the LE client
must
use the value specified in the TLVas an
operating parameter (if the LE client recognizes the ELAN type). Afew examples of
situations where TLVsmight be beneficial are as follows:
vWhen ELANs are spread over large geographic locations, the default timeout
values for LE clients may be insufficient. These timeouts can be controlled for all
LE clients by specifying their value in a TLVat the LECS.
Overview of LAN Emulation
Chapter20. Overview of LAN Emulation 263