Introduction to SNA Capabilities of Tandem NonStop Systems

Connections
Introduction to SNA Capabilities of Tandem NonStop Systems–134597
3-4
Tandem Controllers
Token-Ring networks require the IEEE 802.5 physical interface.
Tandem Controllers
Tandem provides communications controllers that support the types of connections and
electrical interfaces you require, as indicated in Table 3-5.
Dialed Connections
SNAX/XF supports the establishment of SDLC connections through V.25 bis modems
that can automatically dial or receive calls across the general switched telephone
network. V.25 bis support requires use of the RS-232 electrical interface and the 3605 or
3650/3651 controller (K-series servers) or 3880 concentrator (S-series servers).
Table 3-4. Electrical Interfaces Supported by Each SNAX Access Method
Electrical Interface Max Speed (note 1) SNAX/XF SNAX/APN SNAX/CDF
RS-232 19 kilobits/sec Yes Yes Yes
RS-449/422 (note 2) 64 kilobits/sec Yes Yes Yes
V.35 56 kilobits/sec Yes Yes No
X.21 64 kilobits/sec Yes Yes No
Notes.
1. The maximum speeds shown are for 4 lines per controller; with 1 line per controller, SDLC line speeds can
be up to 256 kilobits/sec.
2. RS-449 is supported in SNAX/XF and SNAX/APN by RS-422.
Table 3-5. Tandem Controllers
Type of
Connection
Electrical
Interface
K-Series Servers S-Series Servers
3604
(note 1)
3605 3650/3651
(note 2)
3616 3880
(note 3)
SDLC or X.25 RS-232 Yes Yes Yes No Yes
RS-449/422 Yes Yes Yes No Yes
V.35 Yes Yes Yes No Yes
X.21 No Yes Yes No Yes
Token-Ring IEEE 802.5 No No No Yes Not at G01.00
Notes.
1. SNAX/CDF can use only the 3604 controller.
2. The 3650 Communication Subsystem family consists of model numbers 3651-n. The 3650 connects to the
Tandem system through a pair of 6110 communications interface units.
3. The Tandem 3880 ServerNet wide area network concentrator.