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Glossary
114
December, 2005 Vodavi Telenium IP Product Guide
mobility ▪ presence ▪ collaboration ▪ convergence
RF radio frequency (RF): alternating current (AC) having characteristics such that, if the current is
input to an antenna, an electromagnetic (EM) field is generated suitable for wireless broadcasting
and/or communications.
RIP RIP (Routing Information Protocol) is a widely-used protocol for managing router information
within a self-contained network such as a corporate local area network () or an interconnected
group of such LANs. RIP is classified by the Internet Engineering Task Force (IETF) as one of
several internal gateway protocols (Interior Gateway Protocol).
Router A device that is an interface between two networks. These highly intelligent devices redirects
packets between similar and dissimilar LANs. Routers normally support multiple protocols
operating mostly at Layer 3 of the OSI model.
Routing Switch A new breed of router that in addition to routing TCP/IP packets (Internet packets) also routes
cells, frames, and other types of packets. For example, a routing switch may be used by a
carrier for an ATM switching application. In a LAN, a large switch may incorporate routing
capabilities in order to reduce the number of devices required to provide LAN and WAN
connections.
RTP Real-time Transport Protocol. An IETF standard for streaming real-time multimedia over IP in
packets. It supports the transport of real-time data like interactive voice and video over packet
switched networks. It is a thin protocol providing support for content identification, timing
reconstruction, loss detection and security. Like RTCP, typically runs on top of UDP.
RTCP Real-Time Control Protocol. Used for control and diagnostic on RTP sessions.
Server A computer that responds to requests from a client computer or other client device.
SIP Session Initiation Protocol. An Application Layer (Layer 7 of the OSI Reference Model) protocol
for the establishment, modification and termination of conferencing and telephony sessions over
an IP-based networks.
SNMP Simple Network Management Protocol. An application-layer protocol used for managing and
monitoring network nodes. Not all network devices support SNMP.
Socket A virtual connection using TCP/IP. A socket consists of a host’s IP address plus a port number.
Soft Phone A software based application that emulates a telephone, most commonly deployed on PCs and
PDAs.
SONET Synchronous Optical NETwork. A very high-bandwidth optical network technology carrying
circuit-switched frames over fiber. Ranges from 51.84 Mbps to 13.21 Gbps.
Static IP
Address A static IP address is a number that is assigned to a computer by an Internet service provider
(ISP) to be its permanent address on the Internet. Computers use IP addresses to locate and talk
to each other on the Internet. Contrast with dynamic (see DHCP).
STUN STUN (Simple Traversal of UDP over NATs) is a network protocol allowing a client behind NAT (or
multiple NATs) to find out its public address, the type of NAT it is behind and the Internet side
port in use. This information is used to set up UDP communication hosts that are behind NAT
routers.
Subdomain Also called a child domain, a domain that is part of a larger domain name in DNS hierarchy. DNS
hierarchy consists of the root-level domain at the top, underneath which are the top-level
domains, followed by second-level domains and finally subdomains.
Subnet A portion of a network that shares a common address component. On TCP/IP networks, subnets
are defined as all devices whose IP addresses have the same prefix. For example, all devices with
IP addresses that start with <100.100.100> would be part of the same subnet. Dividing a
network into subnets is useful for both security and performance reasons. IP networks are
divided using a subnet mask.