Avaya M-ACCF, User Manual, Page: 21 / 114

Chapter 1 Overview
Avaya M770 M-ACCF/SF ATM Access Modules User’s Guide 5
Emulated LAN Connections
LECs and LESs communicate with each other by means of ATM virtual channel
connections (VCCs). Control signals and data transmissions are handled by separate
VCCs: Control VCCs and Data VCCs.
Figure 1.1 Basic LAN Emulation Client Connections
Control VCCs
The control VCCs carry control traffic such as LE_ARP requests and responses. On
initialization, control VCCs are established between LEC and LES (bi-directional
control-direct VCC and control-distribute VCC) as well as a bi-directional configuration
VCC between LEC and LECS. Characteristics of the control VCCs are summarized
in Table 1.1.
Table 1.1 Control VCCs
VCC Name From/To Information carried
Initialized
by
Duration
Configuration LEC<==>LECS LEC requests and
receives
configuration
information from
LECS, including LES
address
LEC While
needed
Control-direct LEC<==>LES LEC sends and
receives controls
from LES, including
LE_ARP information LEC Membership
of LEC in
ELAN