Glossary
GL-4
Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide (SIP)
OL-3410-01
IP Internet Protocol. Network layer protocol in the TCP/IP stack offering a con nectionless internetwork
service. IP provides features for addressing, type-of-serv ice specification, fragmentation and
reassembly, and security. Defined in RFC 791.
IVR Interactive voice response. Term used to describe systems that provide information in the form of
recorded messages over telephone lines in response to user input in the form of spoken words or, more
commonly, DTMF signaling.
L
LDAP Lightweight DirectoryAccess Protocol
LEC local exchange carrier.
Location Server A SIP redirect or proxy server uses a location server to get information about a caller’s location.
Location services are offered by location servers.
M
MGCP Media Gateway Control Protocol.
MWI message waiting indication.
µ-law North American companding standard used in conversion between analog and digital signals in PCM
systems. Similar to the European a-law. See also a-law and companding.
N
NAT Network Address Translation. Mechanism for reducing the need for globally unique IP addresses.
NAT allows an organization with addresses that are not globally unique to connect to the Internet by
translating those addresses into globally routable address spaces. Also known as Network Address
Transla tor.
NSE packets Real-Time Transport Protocol (RTP) digit events are encoded using the Named Signaling Event (NSE)
format specified in RFC 2833, Section 3.0.
NAT Server Network Address Translation. an Internet standard that enables a local-area network (LAN) to use one
set of IP addresses for internal traffic and a second set of addresses for external traffic.
NTP Network Time Protocol. Protocol built on top of TCP that assures accurate local time-keeping with
reference to radio and atomic clocks located on the Internet. This protocol is capable of synchronizing
distributed clocks within milliseconds over long time periods.