Cisco ASA 5505 - Manual (Page 1960)

Glossary
GL-22
Cisco ASA 5500 Series Configuration Guide using the CLI
VoIP Voice over IP. VoIP carries normal voice traffic, such as telephone calls and faxes, over an IP-based
network. DSP segments the voice signal into frames, which are coupled in groups of two and stored
in voice packets. These voice packets are transported using IP in compliance with ITU-T specification
H.323 .
VPN Virtual Private Network. A network connection between two peers over the public network that is
made private by strict authentication of users and the encryption of all data traffic. You can establish
VPNs between clients, such as PCs, or a
headend , such as the ASA.
virtual firewall See security context .
VSA Vendor-specific attribute. An attribute in a RADIUS packet that is defined by a vendor rather than by
RADIUS RFCs. The RADIUS protocol uses IANA-assigned vendor numbers to help identify VSAs.
This lets different vendors have VSAs of the same number. The combination of a vendor number and
a VSA number makes a VSA unique. For example, the cisco-av-pair VSA is attribute 1 in the set of
VSAs related to vendor number 9. Each vendor can define up to 256 VSAs. A
RADIUS packet
contains any VSAs attribute 26, named Vendor-specific. VSAs are sometimes referred to as
subattributes.
W
WAN wide-area network. Data communications network that serves users across a broad geographic area
and often uses transmission devices provided by common carriers.
WCCP Web Cache Communication Protocol. Transparently redirects selected types of traffic to a group of
web cache engines to optimize resource usage and lower response times.
Websense A content filtering solution that manages employee access to the Internet . Websense uses a policy
engine and a URL database to control user access to websites.
WEP Wired Equivalent Privacy. A security protocol for wireless LAN s, defined in the IEEE 802.11b
standard.
WINS Windows Internet Naming Service. A Windows system that determines the IP address associated with
a particular network device, also known as name resolution. WINS uses a distributed database that is
automatically updated with the
NetBIOS names of network devices currently available and the IP
address assigned to each one.WINS provides a distributed database for registering and querying
dynamic
NetBIOS names to IP address mapping in a routed network environment. It is the best choice
for NetBIOS name resolution in such a routed network because it is designed to solve the problems
that occur with name resolution in complex networks.
X
X.509 A widely used standard for defining digital certificates. X.509 is actually an ITU recommendation,
which means that it has not yet been officially defined or approved for standardized usage.