Local Area Networks And The Lat Architecture; Wide Area Networks And Statistical Multiplexers - Digital Equipment MUXserver 100 Reference Manual

1.2 LOCAL AREA NETWOFIKS AND THE LAT
ARCHITECTURE
The individual computers on the LAN are called network nodes. The
MUXserver 100 and the nodes it comrnunicates with must support the Local
Area Transport (LAT) architecture. Thle LAT architecture manages the sessions
that the MUXserver 100 establishes between its remote terminals and network
nodes.
Support of the LAT architecture requires that LAT software reside on both the
MUXserver 100 and on the nodes with which it interacts. The LAT software
that resides on the MUXserver 100 is called server software. The server soft-
ware is down-line loaded to the server from one of the nodes on the network.
The LAT software residing on the other LAT nodes is the service node soft-
ware, so called because it resides on nodes that provide services to MUXserver
100 terminal users.
To down-line load the server, a system manager first installs the server soft-
ware on an Ethernet node which supports the Digital Network Architecture
(Phase IV). That node is then a load host. When power is applied to the
MUXserver 100, the load host down-line loads the software over the network to
the server. The MUXserver 100 INITIALIZE and RESTART commands also
generate a down-line load.
System managers can install the server software on a number of load hosts.
DIGITALTM recommends that the network manager establish a minimum of two
load hosts on every LAT network, with at least one load host for every ten
MUXserver 100 units on larger networks.
1.3 WIDE AREA NETWORKS AND STATISTICAL
MUL TIPLEXERS
As shown in Figure 1-1, the terminals at the remote site connect directly to
DECmux II statistical multiplexers which communicate over composite links by
means of the leased lines to the MUXserver 100 on the LAN. The interface to
the leased lines being by means of suitable modems. This wide area network
gives remote users access to LAN facilities from any geographic location which
has access to the leased lines.
CHAPTER 1 THE MUXserver 100 ENVIRONMENT 3