APN Configuration and Management Manual

Configuring for Ethernet Support

SNAX/XF and SNAX/APN Configuration and Management Manual—425836-006

10-4

Multipurpose Configuration

In an Ethernet network, a NonStop system can communicate with a variety of devices

and perform a variety of functions over one SNAX line. For example, SNAX/APN can

support parallel LU-LU sessions, communicate with SNA terminals, and function as a

workstation server. Figure 10-3 shows SNAX/APN performing each of these functions

with a separate remote node. However, SNAX/APN can perform all three tasks with a

single remote node.

The Architecture of Ethernet Networks

The IEEE Specifications

The IEEE 802 committee has created a set of LAN standards and protocols for the

physical and data link layers of the OSI model (see Figure 10-4

on page 10-6). The

data link layer has been subdivided into two sublayers: the medium access control

(MAC) layer and the logical link control (LLC) layer. There are three MAC technologies,

that have associated physical media below them:



802.3—a bus topology using a carrier sense multiple-access/collision detect

(CSMA/CD) access method



802.4—a bus topology using a token-passing access method

Figure 10-3. NonStop System on a Heterogeneous LAN

AS/400 System-

LUs With Parallel Sessions

HP NonStop

System

IBM

Mainframe

3270 Terminals

Communicating Through

Workstation Clients

VST1003.vsd