OSI/AS Configuration and Management Manual

Introduction
OSI/AS Configuration and Management Manual—424119-001
1-11
Implemented Standards
Implemented Standards
The following subsections list some of the standards implemented by the OSI/AS
processes:
•
Subnetwork Protocols on this page
•
Transport Layer Protocols on page 1-12
•
Session Layer Protocol on page 1-12
•
Presentation Layer Protocol on page 1-13
•
ACSE Protocol on page 1-13
Subnetwork Protocols
Subnetwork protocols compose Layer 1 through Layer 3 of the OSI Reference Model.
OSI/AS supports both local area networks (LANs) and wide area networks (WANs) and
can provide Transport Layer through ACSE (Application Layer) services over either of
these subnetwork types.
Wide Area Networks (WANs)
For communication over WANs, OSI/AS uses the X25AM access method to provide
NSP services. Table 1-1 shows the subnetwork protocols that X25AM implements.
Local Area Networks (LANs)
For communication over LANs, OSI/AS uses the TLAM (for D-series releases) or PAM
(for G06 and above releases) to provide NSP services. TLAM provides access to
CSMA/CD LAN networks (PAM and SLSA together provide access to CSMA/CD
LANs for G06 and above releases). Table 1-2
shows the Layer 1 through Layer 3
protocols for LANs.
Table 1-1. Protocols Supported by X25AM
Layer Standard
Network Layer CCITT X.25 1980 and 1984
Data Link Layer CCITT X.25 1980 and 1984
Physical Layer EIA RS-232C, EIA RS-449, and CCITT X.21
Table 1-2. Protocols Supported by TLAM
Layer Standard
Network Layer ISO 8473 (OSI IP)
Data Link Layer
•
Logical link sublayer
•
Media access sublayer
IEEE 802.2 (LLC1)
IEEE 802.3 (CSMA/CD)
Physical Layer 50-ohm, coaxial baseband cable