Avaya ESS User Manual page 54

ESS Overview
Once in control on Port Network 4, the ESS server assumes control of Port Network 5 through
the EI board.
Figure 21: ATM, single ESS server, multiple nodes in a takeover scenario
PN #1
Port Network Control Link (EAL)
IP Connection into Control Network
Server or Network Failure
VoIP Path
DSIC LInk
The Users in Port Network 1 through 3 can make station-to-station calls to each other but
cannot make station-to-station calls to users in Port Networks 4 through 6. The reverse is also
true, where users in Port Networks 4 through 6 cannot make calls to users in Port Networks 1
through 3.
54 Avaya Enterprise Survivable Servers (ESS) Users Guide
S8710 Media Server
(Main Server)
disc COMPACT
1
2
UID
disc COMPACT
1
2
UID
PN #2
PN #3
S8700 ESS Server
(1st Alternative)
PN #4
ATM ATM
CSS / EI (Fiber)
ATM / ATM-EI (Fiber)
Dup Link
Out of Service
PN #6
PN #5