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Glossary
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December, 2005 Vodavi Telenium IP Product Guide
mobility ▪ presence ▪ collaboration ▪ convergence
Subnet Mask A mask used to determine what subnet an IP address belongs to. A host ready to send data
over the network compares its own IP address/subnet mask combination with the IP address of
the destination host. If it determines that the other host is on another network, the sending host
send its data to its default gateway and not directly to the destination host. An IP address has
two components, the network address and the host address.
Subnetting The use of a subnet mask to create a subnet.
SWAN SWAN (Structured Wireless-Aware Network): a technology that incorporates a WLAN into a wired
wide-area network (WAN). SWAN technology can enable an existing wired network to serve
hundreds of users, organizations, corporations, or agencies over a large geographic area.
Switch(1) A device that selects paths or circuits. Data switches work at Layer 1 (Physical) and 2 (Data Link)
of the OSI model with emphasis on Layer 2. A switch looks at incoming data to determine the
destination address. Based on that address, a transmission path is set up through the switching
matrix between the incoming and outgoing physical communications ports and links. Data
switches also typically contain buffers, which can hold data packets in temporary memory until
the necessary resources are available to allow the data packets to be forwarded. They are not as
intelligent as routers but are much faster. Also, a computer for switching telephone calls, as in a
PBX or key system.
Switch(2) A computer for switching telephone calls, as in a PBX or key system.
T1 Trunk Level 1. A digital transmission link with a total signaling speed of 1.544 Mbps. It can be
set up as a channelized service (e.g., for 24 phone lines) or as an unchannelized raw bit stream
for data.
T3 The North American standard for DS-3. It operates at a signaling rate of 44.736 Mbps or 28 T-
1s. It is commonly referred to as 45 megabits per second. See DS-3 for more information.
TCP Transmission Control Protocol. This protocol corresponds to OSI layers 4 and 5, transport and
session. It is a transport layer, connection-oriented , end-to-end protocol. It provides reliable,
sequenced, and unduplicated delivery of bytes to a remote or local user. TCP provides reliable
byte stream communication between pairs of processes in hosts attached to interconnected
networks. It is the portion of the TCP/IP protocol suite that governs the exchange of sequential
data.
TCP/IP Transmission Control Protocol/Internet Protocol: When TCP is combined with IP for routing,
various protocols can be transported over the Internet or private networks. Two recent
adaptations of Internet technology, the intranet and the extranet, also make use of the TCP/IP
protocols.
TDM Time-Division Multiplexing. A means of creating multiple circuits on a single transmission channel
by rapidly connecting terminals one at a time in a recurring time ordered sequence. Traditional
digital telephone switches employ TDM technology.
Telnet An application-layer protocol for establishing a terminal session with a computer or other network
device.
Throughput Throughput is a summation of the aggregate bandwidth available for transmission. Throughput
can also reference the aggregate traffic transported on a specific network segment.
TLD (Top level
Domain) Top Level Domain refers to the suffix attached to Internet domain names. There are a limited
number of predefined suffixes, and each one represent a top-level domain. Current top-level
domains include: COM, GOV, EDU, ORG and NET. There is also a TLD designated for each
country (.US, .KR, .UK)
TLS Transport-Layer Security Protocol: A protocol that provides communications privacy and security
between two applications communicating over a network.