Operation Manual

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Glossary
The Glossary provides an explanation of terms and acronyms discussed in this user guide.
10BASE-T: IEEE 802.3 specification for 10 Mbps Ethernet over twisted pair wiring.
100BASE-Tx: IEEE 802.3 specification for 100 Mbps Ethernet over twisted pair wiring.
ATM: Asynchronous Transfer Mode: A method of transfer in which data is organized into 53-byte cell units.
ATM cells are processed asynchronously in relation to other cells.
BC: Broadcast: Communication in which a sender transmits to everyone in the network.
BER: Bit Error Rate: Percentage of Bits that contain errors relative to the total number of bits transmitted.
Bridge: A device that connects two networks and decides which network the data should go to.
Bridge Mode: Bridge Mode is used when there is one PC connected to the LAN-side Ethernet or USB port.
IEEE 802.1D method of transport bridging is used to bridge between the WAN (ADSL) side and the LAN
(Ethernet or USB) side, i.e., to store and forward.
CBR: Constant Bit Rate: A constant transfer rate that is ideal for streaming (executing while still downloading)
data, such as audio or video files.
Cell: A unit of transmission in ATM, consisting of a fixed-size frame containing a 5-octet header and a
48-octet payload.
CHAP: Challenge Handshake Authentication Protocol: Typically more secure than PAP, CHAP uses
username and password in combination with a randomly generated challenge string which has to be
authenticated using a one-way hashing function.
CLP: Cell Loss Priority: ATM cells have two levels of priority, CLP0 and CLP1. CLP0 is of higher priority, and
in times of high traffic congestion, CLP1 error cells may be discarded to preserve the Cell Loss Ratio of the
CLP0 cells.
CO: Central Office: In a local loop, a Central Office is where home and office phone lines come together and
go through switching equipment to connect them to other Central Offices. The distance from the Central
Office determines whether or not an ADSL signal can be supported in a given line.
CPE: Customer Premises Equipment. This specifies equipment on the customer, or LAN, side.
CRC: Cyclic Redundancy Checking: A method for checking errors in a data transmission between two
computers. CRC applies a polynomial function (16 or 32-bit) to a block of data. The result of that polynomial is
appended to the data transmission. Upon receipt, the destination computer applies the same polynomial to
the block of data. If the host and destination computer share the same result, the transmission was
successful. Otherwise, the sender is notified to re-send the data block.
DHCP: Dynamic Host Configuration Protocol: A communications protocol that allows network administrators
to manage and assign IP addresses to computers within the network. DHCP provides a unique address to a
computer in the network which enables it to connect to the Internet through Internet Protocol (IP). DHCP can
lease and IP address or provide a permanent static address to those computers who need it (servers, etc.).
DMZ: Demilitarized Zone: A computer Host or network that acts as a neutral zone between a private network
and a public network. A DMZ prevents users outside of the private network from getting direct access to a
server or any computer within the private network. The outside user sends requests to the DMZ, and the DMZ
initiates sessions in the public network based on these requests. A DMZ cannot initiate a session in the