Alcatel Carrier Internetworking Solutions Switch/Router Back-to-Back Frame Relay Congurations

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Back-to-Back Frame Relay Configurations
Frame Relay switching modules may be connected “back-to-back” without an intervening
Frame Relay network or switch. Such connections are made by using private leased lines,
such as T1 lines, instead of public Frame Relay networks usually over large geographic
distances.
No special user configuration is necessary for back-to-back connections. The WSX software
automatically detects that a Frame Relay Logical DCE (i.e., Frame Relay switch) is not present
and that there is another Frame Relay Logical DTE (i.e., another WSX, FRAD, bridge/router) on
the other end of the WAN connection. The WSX then automatically brings up a Permanent
Virtual Circuit identified with a DLCI of 32, which is the same value IBM uses in this scenario.
The WSX does not bring up PVC DLCI 32 until it knows that it has established communication
with another DTE device rather than a Frame Relay switch.
Back-to-Back Frame Relay Configuration Using Serial Ports
WSX
TT
TT11 11 LL LLiiiinn nnee ee
SS
SSee eerr rriiiiaa aallll
DD
DDTT TTEE EE-- --DD DDCC CCEE EE
WSX
TT
TT11 11
MM
MMuu uulllltt ttiiiipp ppllllee eexx xxee eerr rr
TT
TT11 11
MM
MMuu uulllltt ttiiiipp ppllllee eexx xxee eerr rr
CC
CCaa aabb bbllllee ee
SS
SSee eerr rriiiiaa aallll
DD
DDTT TTEE EE-- --DD DDCC CCEE EE
CC
CCaa aabb bbllllee ee
OO
OOmm mmnn nniiii SS SSww wwiiiitt ttcc cchh hh// //RR RRoo oouu uutt ttee eerr rr
OO
OOmm mmnn nniiii SS SSww wwiiiitt ttcc cchh hh// //RR RRoo oouu uutt ttee eerr rr