Lantronix ETS, Справочное руководство

Страница: 296 / 312

LAT Glossary
Glossary-4
LAT Local Area Transport. LAT is a Digital Equipment Corporation proprietary
network communication protocol. The protocol is based on the idea of a
relatively small, known number of hosts on a local network sending small
network packets at regular intervals. LAT will not work on a wide area network
scale as TCP/IP does, as it cannot distinguish large numbers of nodes. For
local networks, however, LAT is usually faster and less prone to pauses than
TCP/IP.
LAT also allows remote connections to services and other network devices,
about which TCP/IP has no understanding. The fact that the ETS supports both
LAT and TCP/IP protocols transparently means that you are not bound by the
limitations of either protocol.
login service Created when the ETS is configured to allow users to log in from the network
(as opposed to logging in from the serial ports). The Server advertises a new
service with the same name as the server. LAT users who connect to the
service will not be connected to a physical port or device; they will be given a
virtual port on the Server instead. Although they obtain a Local> prompt and
can issue commands as if they were physically connected to the Server. When
they log off the Server, their virtual port disappears. Each login to the Server
consumes a virtual port.
MAU Medium Attachment Unit. This is a small device used as a transceiver between
a Thinwire network cable and an AUI cable or a Thickwire cable and an AUI
cable. It consists of the physical adapter as well as the circuitry needed to
convert signals from one medium to the other.
MMJ Modified Modular Jack. These are the 7-pin connectors that the Server uses to
connect serial terminal lines to terminal devices. They are much smaller and
easier to manage than the traditional RS-232 25-pin connectors. Many non-
terminal devices such as printers and modems still use RS-232 connectors, so
adapters are frequently needed. MMJ jacks can be distinguished from the
similar RJ-12 jacks by their side locking tabs (RJ-12 locking tabs are center-
mounted).
MOP Maintenance Operations Protocol. MOP is a Digital protocol for Ethernet
network traffic. The protocol is used for remote communications between
hosts and devices on the network. Terminal servers use this protocol to
download code from a host quickly and easily. For networks where LAT and
MOP are the dominant network services, MOP is the simplest way to boot the
Server.
At boot time, the Server broadcasts a request on the network for a load file, and
a MOP host will respond and send the file. MOP is also used to signal the
Server of an NCP request or connection from another host, and is the protocol
that TSM is based on.