TMS zl Management and Configuration Guide ST.1.0.090213

B-25
Glossary
priority The position of an object relative to other objects. A policy in the top position
(1) is applied first, then the next policy, then the next. As soon as a packet
matches a policy, that policy is applied and all other policies are ignored. A
module in top position (255) is elected master of an HA cluster.
priority VLAN A VLAN from which you can gain management access regardless of traffic
volume or workload.
protocol anomaly Deviation of a protocol from standard specifications (set by RFCs and com-
mon practice). Protocol anomalies are often a sign of an attack, for which a
signature has not yet been recognized.
protocol data unit See PDU.
PSK Preshared Key. A text string agreed upon by two parties in advance. In IKE
negotiations, peers can exchange a pre-shared key that is between 8 and 255
characters long to authenticate each other before opening the IKE SA.
Q
QoS Quality of Service. A service provided by some network protocols such that
the network prioritizes traffic or guarantees a particular level of performance
to a type of data flow.
R
RADIUS Remote Authentication Dial-In User Service. An AAA protocol that allows a
server to store all of the security information for a network in a single, central
database. The server stores and manages end-user information so that it can
authenticate the end-users. The server also maps end-users to the services that
they are allowed to access. For more information, see RFC 2865 at http://
www.ietf.org/rfc/rfc2865.txt.
RADIUS server A common type of AAA server. The RADIUS server authenticates end-users,
using protocols such as PAP, CHAP, and EAP. If the end-user passes authentica-
tion, the server authorizes access to the network based on policies such as
valid access times. The server can also authorize the end-user for a specific
level of access by sending dynamic settings for the NAS to enforce. As an
accounting server, the RADIUS server can also be notified when a session
starts and stops.
rate limiting An option for firewall policies that permits limits to be put on the amount of
bandwidth a connection type can use.