Lantronix MPS100 EPS Reference Manual - Page 214

Simple Network Management Protocol. SNMP allows a TCP/IP host running

Page 214 highlights

rwho rwho SAP service SNMP subnet mask Glossary A UNIX feature that enables network hosts to know what users and systems are on the network without actively connecting to them. If rwho is enabled on a host, it both sends and receives network broadcasts containing this information. The packets generally contain the host's name, IP address, and the number and names of the users on the system. Because the broadcasts are periodic (typically 30 seconds to two minutes), hosts that are seen with rwho and then removed from the local host table will reappear later. Rwho usually has to be enabled explicitly on the host system, and may not be enabled on large network environments where the extra network traffic is unacceptable. In this case hosts can be added to the local host table by hand. Service Advertising Protocol. SAP packets, along with RIP packets, allow the Server to broadcast its known routes and services to the network and obtain this information from other routers on the network. Any device on a network that can be connected to and accessed, such as a printer, modem, or a remote computer. Network users can generally see the services available on the network because the nodes that provide these services "advertise" them to the world. In the case of LAT, each service node sends out occasional network messages called multicasts describing what services it is providing and which users are connected to them. The concept of services is specific to LAT and local area networks. TCP/IP and other wide area networks have no such facility. The service will occasionally be used to refer to anything that can be connected, whether LAT or not. Simple Network Management Protocol. SNMP allows a TCP/IP host running an SNMP application to query other nodes for network-related statistics and error conditions. The other hosts, which provide SNMP agents, respond to these queries and allow a single host to gather network statistics from many other network nodes. The Server provides this SNMP agent only; it cannot generate queries to other hosts. It only responds to them. A "filter" that tells the Server whether a node is on the local network or a remote network. The Server supports Telnet connections across networks through the use of gateways, using gateway hosts to forward messages across network boundaries. The Server uses the subnet mask as a filter; if the Server's IP address and the remote IP address appear the same after the filter, the remote host is assumed to be on the same local network. Otherwise, the gateway is used. The mask itself is a list of bits that should be enabled in the result-a 1 in the mask means to let that bit in the IP address through, and 0 means do not. For example, address 192.1.2.22 with mask 255.255.0.0 becomes 192.1.0.0. For network purposes, host 192.1.5.12 is on the same network, based on the mask specified. In this case, a gateway would not need to be accessed. A host at Glossary-6

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rwho
Glossary
Glossary-
6
rwho
A UNIX feature that enables network
hosts
to know what users and systems
are on the network without actively connecting to them. If rwho is enabled on
a host, it both sends and receives network broadcasts containing this
information. The packets generally contain the host’s name, IP address, and the
number and names of the users on the system.
Because the broadcasts are periodic (typically 30 seconds to two minutes),
hosts that are seen with rwho and then removed from the local host table will
reappear later. Rwho usually has to be enabled explicitly on the host system,
and may not be enabled on large network environments where the extra
network traffic is unacceptable. In this case hosts can be added to the local host
table by hand.
SAP
Service Advertising Protocol. SAP packets, along with
RIP
packets, allow the
Server to broadcast its known routes and services to the network and obtain this
information from other routers on the network.
service
Any device on a network that can be connected to and accessed, such as a
printer, modem, or a remote computer. Network users can generally see the
services available on the network because the
nodes
that provide these services
“advertise” them to the world. In the case of LAT, each service node sends out
occasional network messages called
multicasts
describing what services it is
providing and which users are connected to them.
The concept of services is specific to
LAT
and local area networks. TCP/IP
and other wide area networks have no such facility. The service will
occasionally be used to refer to anything that can be connected, whether LAT
or not.
SNMP
Simple Network Management Protocol. SNMP allows a TCP/IP host running
an SNMP application to query other nodes for network-related statistics and
error conditions. The other hosts, which provide SNMP agents, respond to
these queries and allow a single host to gather network statistics from many
other network nodes. The Server provides this SNMP agent only; it cannot
generate queries to other hosts. It only responds to them.
subnet mask
A “filter” that tells the Server whether a node is on the local network or a
remote network. The Server supports Telnet connections across networks
through the use of
gateways
, using gateway hosts to forward messages across
network boundaries. The Server uses the subnet mask as a filter; if the Server’s
IP address and the remote IP address appear the same after the filter, the remote
host is assumed to be on the same local network. Otherwise, the gateway is
used.
The mask itself is a list of bits that should be enabled in the result—a 1 in the
mask means to let that bit in the IP address through, and 0 means do not. For
example, address 192.1.2.22 with mask 255.255.0.0 becomes 192.1.0.0. For
network purposes, host 192.1.5.12 is on the same network, based on the mask
specified. In this case, a gateway would not need to be accessed. A host at