16/4Mbps Token-Ring Network Gateway Feature; Host-Gateway Relationship - IBM 3174 Introduction Manual

16/4Mbps Token-Ring Network Gateway feature
The gateway feature provides for data passage between an SNA/SDLC host
processor and workstations and controllers that are attached to the IBM
Token-Ring Network. The gateway feature will operate on an IBM Token-Ring
Network at either 16 or 4Mbps.
The feature can be installed in any of the following controllers: 1 L, 11 L, 1 R, 11 R,
2R, 12R, 51 R, 61 R, 52R, and 62R. The gateway feature does not interfere with the
ability of ring-attached devices to communicate with each other on the ring; nor
does it affect terminals directly attached to the gateway 3174.
Many workstations can be defined to the host VTAM because of the gateway
feature. Depending upon the configuration and controller models involved, it is
possible that up to 250 Token-Ring-attached workstations or controllers can be
defined to VTAM. The addresses are mapped to unique host subchannel or SDLC
addresses. One subchannel or SDLC address is also required for the controller in
which the gateway feature is installed~
DD
Host
3174
MOdel.53R~
I ,
A . . • . • • . . .
:.D . • . . • . . .
J
dl-_--l
Token-Ring
O"'~:'~\~/
, . . . . , . . ;
' > - - - - - - r '
3174 Model IL
with Gateway
Feature
3174 Model 53R
3174
Model3R
Figure 2-2. IBM Token-Ring Network
Host-Gateway Relationship
Adding the gateway feature to the system requires no changes in the host
application program. Nor is there any effect upon normal 3174 Establishment
Controller functions.
Chapter 2. Features and Functions of the 3174 Controller
2-7