SNA NRJE User/Programmer Reference Manual (30292-90006)

26 Chapter1
Introducing SNA NRJE
Introduction
Introduction
Network Remote Job Entry (NRJE) is a data communications
subsystem that provides HP-to-IBM batch communications in a
Systems Network Architecture (SNA) environment. SNA is a
comprehensive specification for distributed data processing networks,
developed by IBM.
SNA NRJE users at remote locations submit jobs to a host system for
processing. The host sends output to SNA NRJE users at the remote
location. SNA NRJE emulates a remote batch workstation as described
below.
SNA NRJE’s relationship to the International Standards Organization
(ISO) and SNA model communications networks is described in Table
1-1, “Relationship Between Network Models.”
A computer network is designed in structured layers. The reason for a
layered approach is to simplify the design of the overall network. Each
layer rests on the next lower layer as a foundation. Each layer provides
a service to the next higher layer in its own node, and relates to its
counterpart layer on another node at a peer level. Direct
communication with another node takes place only at the lowest layer
of a network.
Table 1-1 Relationship Between Network Models
Layer ISO SNA HP
Implementation
7 Application End User* NRJE User
Interface and
Intrinsics
6 Presentation Network Addressable
Unit (NAU) Services
NRJELU Program
5 Session Data Flow Control
4 Transport Transmission Control SNA Transport
Intrinsics
3 Network Path Control
2 Data Link Data Link Control SLDC dRIVER
1 Physical Physical INP (for NRJE/V)
PSI (for NRJE/XL)
*IBM describes SNA with only six layers.