61200.130L1-1 FSU User Manual 27
Chapter 4. Applications
Bisync Application
The FSU can be used to connect IBM 3780/2780 (see IBM manual
number GA27-3004-2) bisync controllers and a host across a
frame relay network. Point-to-point and multi-point configura-
tions are supported at speeds up to 19200 bps. The LLC protocol
(mode 2) is used to provide a reliable transport layer across the
frame relay network. In a multi-point configuration the FSU
performs local spoofing, minimizing traffic across the frame
relay network. Sample network illustrations for both point-to-
point and multi-point are shown in Figures 4-3 and 4-4.
See Table 4-C for an example configuration for the point-to-point
application.
Bisync Bisync
3780 Controller
FEP Host
DTE1
DTE2
DTE1
DTE2
DLCI=17 DLCI=120
FSU FSU
RFC1490/LLC2
UNI
NN
UNI
FRAME RELAY
Figure 4-3
Bisync Point-to-Point