OSI/TS Management Programming Manual

OSI/TS Subsystem Architecture
Introduction
1–2 056786 Tandem Computers Incorporated
OSI/TS Subsystem
Architecture
The OSI/TS subsystem provides Transport Layer services to OSI networks. Figure 1-1
shows the relationships among the various components of the OSI/TS subsystem.
Figure 1-1. OSI/TS Subsystem Architecture
Transport
Network
Data Link
Physical
Layer
OSI/TS
Subsystem
LAN
TLAM
Subsystem
Controllers
50-ohm
Baseband
WAN
X25AM
Subsystem
Controllers
RS-232C,
RS-449,
X.21, V.35
010
An OSI/TS subsystem consists of one kind of process, called the transport service
provider (TSP) process. This process implements services and protocols of the
Transport Layer and of the Internet Protocol (IP) of the Network Layer.
The TSP process requires the services of one or more network service provider (NSP)
processes, which implement other functions of the Network Layer and, for local area
networks, some functions of the Data Link Layer. NSP processes are provided by
X25AM for wide area networks or by TLAM for local area networks.