B. Glossary
60
Internet Protocol (IP).
A network layer protocol that sends datagram packets between Internet
nodes. IP is a connection-less protocol, implying that there is no continuing connection between
communicating endpoints. IP provides addressing, type-of-service (ToS) specification, security,
fragmentation and reassembly features. The most widely used IP version is Internet Protocol
Version 4 (IPv4). The ZIP 4x4 phone supports IP as defined in RFC 791.
Internet Protocol Version 6 (IPv6).
The latest level of the IP that is included in many projects,
including the major computer operating systems. The most obvious improvement in IPv6 over
IPv4 is the lengthening of IP addresses from 32 bits to 128 bits. All servers that support IPv6 will
also support Internet Protocol Version 4.
Intranet.
A restricted-access network that works like the Web, but isn’t on it. Usually owned and
managed by a corporation, an intranet enables a company to share its resources with its
employees without making available confidential information to everyone with Internet access.
IP Address (version 4).
A 32-bit number that identifies each sender or receiver of information sent
across the internet. An IP address has two parts: the network identifier and the identifier of a
specific device on the network. On the Internet itself – between the router that moves packets
between points along the route – only the network part of the address is examined.
IP Security (IPSec).
Security standard produced by the Internet Engineering Task Force (IETF). a
protocol suite that provides all necessary elements for secure communications-authentication,
integrity, and confidentiality-and makes key exchange practical even in larger networks.
Jitter.
Jitter is the deviation in some aspect of the pulses in a high-frequency digital signal or the
period frequency displacement of the signal from its ideal location. The SE system utilizes Jitter
Buffers to compensate for jitter.
Key Management.
The management and handling private keys used for signing or encryption.
The only reasonable way to protect the integrity and privacy of information is to rely upon the
secure use of these keys, including the activities of selection, exchange, storage, certification,
expiration, revocation, changing, and transmission. Most of the work in managing information
security systems lies in the key management.
Lightweight Directory Access Protocol (LDAP).
A software protocol that enables anyone to locate
organizations, individuals, and other resources such as files and devices in a network, whether
on the public Internet or on a corporate intranet. LDAP is a “lightweight” (smaller amount of
code) version of Directory Access Protocol (DAP), which is part of X.500, a standard for directory
services in a network. LDAP is lighter because, in its initial version, it did not include security
features. Described by RFC 2251.
Load balancing.
The mapping (or re-mapping) of work to processors, with the intent of
improving the efficiency of a concurrent computation.
Local Area Network (LAN).
A group of computers and associated devices that share a common
communications line and the resources of a single processor or server within a limited geographic
area, such as an office building. 10BaseT Ethernet is the most commonly used form of LAN. A
hardware device called a hub serves as the common wiring point, enabling data to be sent from
one machine to another over the network. LANs are typically limited to distances of less than 500
meters and provide low-cost, high-bandwidth networking capabilities within a small
geographical area.
Media Access Control (MAC) Address.
A hardware number that uniquely identifies a computer or
other device. Within an Ethernet configuration, the MAC address is a 6-octet address assigned to
the network interface card. When your computer is connected to the Internet, a correspondence