OSI/TS Configuration and Management Manual

Introduction
OSI/TS Configuration and Management Manual—424831-001
1-5
Software Architecture
•
ServerNet Wide Area Network (SWAN) Concentrator
•
Token-Ring ServerNet Adapter (TRSA)
For further general information about G-series software and related S-series hardware
consult the G-Series Highlights and Migration Planning Guide.
Software Architecture
The OSI/TS subsystem includes two types of processes:
•
Transport service provider (TSP) processes, which implement the following:
•
Transport Layer services for wide area networks (WANs) and local area
networks (LANs)
•
Internet protocol (IP) for LANs
•
End system to intermediate system (ES-IS) routing exchange protocol for LANs
•
Subnetwork Dependent Convergence Function (SNDCF) for WANs
•
Network service provider (NSP) processes, which are one of the following I/O
processes defined at system generation:
•
X25AM, which implements the services of the Network Layer and below for
WANs
•
TLAM, which implements the services of the Data Link Layer and below for
LANs. In the case of S-series systems, PAM implements the interface between
the SLSA and OSI/TS subsystems, therefore PAM (along with SLSA) takes care
of the LANs.
Software and hardware for the lower three layers (Network, Data Link, and Physical)
vary, depending on whether communication is over a wide area network or a local area
network.
Figure 1-3
shows how the various layers of the OSI Reference Model are supported for
users of Compaq OSI/TS over both WANs and LANs. LAN* indicates that TLAM will
be used in K-series systems, and PAM will be used for G06 and above releases in S-
series systems. Controller ** indicates that a controller will be used in the case of K-
series systems; and in the case of S-series systems, SLSA and the E4SA Controller will
be used.