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Glossary
111
December, 2005 Vodavi Telenium IP Product Guide
mobility ▪ presence ▪ collaboration ▪ convergence
IP Internet Protocol. The addressing scheme for Internet communications.
IP Address A 32-bit number that identifies each sender or receiver of information that is sent in packets
across the Internet. Every device must have a unique IP address assigned to it, in order to be
reachable via the Internet.
IPSec Short for IP Security, a set of protocols developed by the IETF to support secure exchange of
packets at the IP layer. IPsec has been deployed widely to implement Virtual Private Networks
(VPNs).
IPv4 Internet Protocol, version 4. The current version of IP numbering scheme in use worldwide, using
a unique 32-bit address for each host.
IPv6 Internet Protocol, version 6. IPv6 is the upcoming IP numbering scheme. IP addresses are
lengthened from 32 bits to 128 bits. This extension anticipates considerable future growth of the
Internet and provides relief for what was perceived as an impending shortage of network
addresses. IPv6 will be backward-compatible with IPv4.
IR Wireless The use of wireless technology in devices or systems that convey data through infrared (IR)
radiation. Infrared is electromagnetic energy at a wavelength or wavelengths somewhat longer
than those of red light.
IrDA Infrared Data Association. An industry-sponsored organization set up to create international
standards for the hardware and software used in infrared communication links over a relatively
short distance.
ISDN Integrated Services Digital Network. A system of digital telephone connections. The Basic Rate
Interface (BRI) consists of two 64 kbps plus another lower rate channel to handle signaling.
Primary Rate Interface (PRI) consists of 23 channels plus a signaling channel.
ITU-T International Telecommunication Union (Telecommunication Standardization Sector). An
organization based in Geneva, Switzerland that is the most important telecom standards-setting
body in the world. It has no legal authority to set standards, but when its members agree on a
standard, it effectively becomes a de facto world standard.
Jitter In voice over IP (VoIP), jitter is the variation in the time between packets arriving, caused by
network congestion, timing drift, or route changes. A jitter buffer can be used to handle jitter.
Kbps Kilobits per second. A Kilobit is equal to 1,000 bits of data. A normal modem for use over phone
lines operates between 9.6 and 56 Kbps.
LAN A computer network that spans a relatively small area. Most LANs are confined to a single
building or group of buildings. However, one LAN can be connected to other LANs over any
distance via telephone lines and radio waves. A system of LANs connected in this way is called a
wide-area network (WAN).
Latency The amount of time it takes for a packet of information to arrive at its destination. Usually
measured in milliseconds on LANs and WANs. Also called delay.
LEAP Lightweight Extensible Authentication Protocol: a variant of EAP developed by Cisco Systems.
See EAP
MAC Media Access Control. The MAC address is a 48-bit number represented in Hexadecimal notation,
which is considered a network device’s unique hardware address.
MAN Metropolitan Area Network: A computer network that spans a relatively small area. Most LANs
are confined to a single building or group of buildings. However, one LAN can be connected to
other LANs over any distance via telephone lines and radio waves. A system of LANs connected
in this way is called a wide-area network (WAN).
Mbps Megabits per second. A megabit is 1 million bits of data. Normal LAN speeds over copper wire are
either 10 Mbps (Ethernet) or 100 Mbps (Fast Ethernet).
Megaco A variant of MEdia GAteway COntrol Protocol. See MGCP.