SNAX/APN Application Programming Manual

SNAX/APN Application Programming Manual—420111-001
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About This Manual
About SNAX/APN
SNAX Advanced Peer Networking (SNAX/APN) is a Tandem product that implements
part of the IBM Systems Network Architecture (SNA). SNA defines various node
types, and SNAX/APN implements the Node Type 2.1 (NT2.1) architecture;
SNAX/APN enables a Tandem NonStop system to function as a type 2.1 node.
SNAX/APN has two main functions:
•
Advanced Peer-to-Peer Networking (APPN) that allows a variety of systems to
communicate as peers and to support LU-LU sessions using LU6.2 protocols.
•
Dependent LU Support that enables non-LU6.2 communication between
applications on a Tandem NonStop system and dependent LU devices and
applications in IBM networks. SNAX/APN does not provide dependent LU support
for SNA devices in Tandem subarea networks because SNAX/XF provides this
function .
Advanced Peer-to-Peer Networking (APPN)
To use APPN, you also need Tandem SNAX/APC, which implements the LU6.2—or
Advanced Program-to-Program Communication (APPC)—architecture. This manual
does not cover APPC programming; refer to the SNAX/APC Application Programming
Manual for programming information about SNAX/APC.
Dependent LU Support
A dependent LU is any LU that doesn’t support LU6.2 protocols. Dependent LUs
require the services of a System Services Control Point (SSCP) and they are controlled
by an SSCP_LU session. Type 6.2 LUs do not require the services of an SSCP and
these are called independent LUs.
As part of dependent LU support, SNAX/APN provides two high-level 3270 application
program interfaces (APIs) so specialized knowledge of SNA is not required. These
APIs are the CRT and ITI interfaces.
SNAX/APN also provides dependent LU support with the low-level SNALU interface,
also an API.
This manual describes these three APIs. You need to be familiar with basic SNA
concepts (such as LUs, PUs, and LU-LU sessions) and have a working knowledge of
Tandem application programming.
Dependent LU support for devices in IBM networks requesting LU-LU sessions with
Tandem applications (logon) requires the use of a Tandem logon facility. SNAX/APN
(LEN Node) provides dependent LU support using only the extended logon facility
(XLF). SNAX/APN-EN (End Node) provides dependent LU support using both XLF
and the enhanced logon facility (ELF).