TMS zl Management and Configuration Guide ST.1.2.100916

B-29
Glossary
SNMP trap A message which is initiated by a network element and sent to the network
management system. For example, if PCM+ is configured as a trap destination,
the TMS zl Module can send SNMP traps to PCM+.
SNMP community A group that devices that run SNMPv1/v2c belong to. It helps define where
information is sent. These devices will not respond to SNMP messages that
are from other SNMP communities.
source NAT Network address translation in which the source IP address is replaced by
another IP address as the packet crosses a network boundary.
source routing A process in which a sender specifies the route by which a packet will travel.
As an attack technique, the sender specifies a route to see if the route is
successful, then learns legitimate paths from the failed and successful routing.
source zone The firewall zone from which a packet is sent.
SPF Shortest Path First. An algorithm used in OSPF to determine which route to
a destination is the fastest.
SPI Security Parameters Index. One of the three factors that identifies an SA. An
SPI identifies the session key and algorithm used to protect the data being
transported.
split brain A situation that results when two network devices — usually the members of
an HA cluster — attempt to perform the same function using the same IP
addresses, but they cannot or do not detect each other.
SSH Secure SHell. A program/network protocol that allows an end-user to log on
to another computer over a network, execute commands in the remote
machine’s OS, and move files from one machine to another. SSH provides
strong authentication. It secures communications over unsecured channels
and can be used when tunneling. For more information, see the SSH Internet
Draft at http://www.free.lp.se/fish/rfc.txt.
SSL Secure Socket Layer. Used for securing the transmission of messages over
insecure networks such as the Internet, SSL works by using asymmetric keys
to encrypt message data.
startup-config The settings that have been saved to the module’s flash memory. When the
module is booted, it reads settings from this file. See also running-config.
stateful A firewall or protocol that maintains session information for every connection
that passes through it.
stateless A firewall or protocol that does not maintain session information for connec-
tions that pass through it.