User`s guide

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TCP/IP Network Basics
LAN Interface Overview
Within the site LAN, every device (PC, router, server, etc.) is called a host.
A host is any device on a network that has a TCP/IP address. TCP/IP
addresses are called
IP addresses, and each device on the network must
have a unique IP address. A typical IP address for a device is
156.140.105.50. In general, communication within the Site LAN and to
Private LANs is behind a
firewall.
Communication among devices on the Site LAN is controlled by
routers.
A router is a host that interfaces with other networks and can move data
(called packets) from one network to another or can move data within the
network, depending on the IP addresses of the hosts that are
communicating with each other.
The
servers on the Site LAN can supply addressing and naming services,
such as Dynamic Host Configuration Protocol (DHCP) to automatically
assign IP addresses to hosts on the network or Domain Name Service
(DNS) or Windows Internet Naming Service (WINS) that allow hostnames
to be associated with their IP addresses.
Private LAN
Topology
A Private LAN (also called a local or isolated network) can operate as a local
network (not connected to any other network) or can be connected to a site
LAN or to another local network. This figure shows an example private LAN
with three hosts (PC and two instruments). Communication between the PC
and the instruments is via a
switch or hub. You can also connect a single
instrument to a PC by using a
crossover cable.
Typical Private LAN
Instrument
Ethernet
Hub or Switch
Instrument
PC