Lantronix ETS Reference Manual page 295

Glossary
gateway
hardware address
host
host table
ICMP
IP address
A TCP/IP host that can access two or more different Ethernet networks. As
such, it can forward messages across networks that other hosts would not be
able to access. The host generally has multiple IP addresses, one for each
network. For example, a gateway might "live" at addresses 192.0.1.8 and
193.0.1.8. Hosts wishing to forward messages may address the messages to the
gateway which will then pass them on to the other network. For example, if an
ETS at address 192.0.1.33 wished to talk to a host at address 196.0.1.58, he
would have to go through a gateway machine on his network. The gateway
would forward messages between networks 192.0.1 and 196.0.1. See subnet
mask.
Every node has a hardware address that is unique across all networks. If you
know a node's hardware address, you should be able to identify the exact piece
of equipment that goes with it. Hardware addresses are generally set up by the
company that manufactured the equipment and should never change. The
hardware address is usually specified as a list of six hexadecimal numbers
separated by dashes, such as "ae-34-2c-1d-69-f1." The hardware address for
your ETS is shown on a label on the rear of the unit. See network address.
Generally a node on a network that can be used interactively, or logged into,
usually an to interactive computer. In the ETS command set, host is used to
refer to a TCP/IP node, rather than TCP/IP and LAT nodes.
For example, the Show Hosts command displays only the known TCP/IP
nodes.
A list of TCP/IP hosts on the network along with their IP addresses. Storing
this list locally means users wishing to connect to these hosts can use text
names (rather numeric IP addresses) without using a nameserver. See the Set
Telnet Host and Show Hosts commands and Local Host Table on page 2-10 for
more information.
Internet Control Message Protocol. ICMP messages are sent by TCP/IP nodes
in response to errors in TCP/IP messages or queries from other nodes. They are
sent, for example, when a node sends a packet to an incorrect gateway host, or
when a network packet expires. ICMP messages may also be sent as
broadcasts, not just sent to a specific host. The ETS counters for ICMP
messages may be helpful for detecting network problems.
In the case of TCP/IP networks, each node has a software or IP address that is
configurable by the managers of the nodes. The software address is usually
specified as four decimal numbers separated by periods (for example,
197.49.155.247). In this case, each number must be between zero and 255, and
each corresponds to a different network or sub-network. Depending on how
many other nodes and networks a node can "see" on its network, addresses are
either assigned to nodes (in the case of large, cross-country networks) or
chosen randomly (for small networks that do not connect to the outside world).
Each software address should be unique across all the networks it can access.
See network address.
gateway
Glossary-3