Glossary

A

access interfaces

The connection between you and the telephone company's central office. The access interface is what allows you to access and obtain services such as ISDN. ISDN provides two types of access interfaces: Basic Rate Interface (BRI) and Primary Rate Interface (PRI).

analog technology

A method of voice transmission that converts voice to electrical signals and amplifies the signals so they can be heard over long distances.

bandwidth

Defines the amount of data that can flow through a channel. The greater the bandwidth, the more data that can travel at one time.

Basic Rate Interface (BRI)

An access interface that most small businesses and individuals use for ISDN. For this service, the telephone company divides the connection between you and the central office into three separate channels, two 64 Kbps B (bearer) data channels and one 16 Kbps D control channel. This service is called 2B+D.

B channel

Also called a Bearer channel. It is a circuit-switched digital channel used to carry data, voice, video, or fax across ISDN.

BRI

See Basic Rate Interface (BRI).

caller ID

A service provided by the telephone company, where the number of the caller is relayed to the number called. The number of the caller can appear on an ISDN telephone, an LCD screen, a computer screen, or another device.

Centrex

A call management service that the local telephone company provides at their site where you get local switching features similar to those an on-site PBX provides.

Challenge Handshake Authentication Protocol (CHAP)

One of two authentication protocols (PAP and CHAP) used by OpenROUTE Networks routers. CHAP is the Challenge Handshake Authentication Protocol, which requires the local router to send a challenge to the connecting router. The router anticipates a specific response. If the connecting router answers with the anticipated response, communication between the two routers continues, if not, the communication channel shuts down.

CHAP

See Challenge Handshake Authentication Protocol (CHAP).

Circuit Switched Data (CSD)

Phone calls with data only instead of voice.

Circuit Switched Voice (CSV)

Traditional telephone service. The voice call goes through several switches before it reaches the final destination.

compression

A process for reducing the number of bits required to transmit information. For ISDN, the result of compression is increased data transmission speed.

CSD

See Circuit Switched Data (CSD).

CSV

See Circuit Switched Voice (CSV).

D channel

Used to control the flow of data through the network: out-of-band call setup and teardown and maintenance of overhead functions, such as signaling between telephone company switches and network monitoring.

device

Physical hardware entity within the router. Each physical LAN or WAN connection on the router corresponds to one device. Some devices (such as, ISDN equipment) can support multiple interfaces.

digital technology

The basis upon which ISDN exists. Digital technology breaks information down into strings of ones and zeros enabling fast transmission of data.

DRAM

See Dynamic Random Access Memory (DRAM).

Dynamic Random Access Memory (DRAM)

A type of storage that the computer accesses at frequent intervals. This memory runs the system software and maintains routing tables.

firewall

A combination of hardware and software that prevents unauthorized access to internal networks.

flash

Programmable memory that is for system storage load and is used in the Integrated Boot Device (IBD).

functional devices

Perform tasks on an ISDN. A TE2, TE1, TA, and NT1 are functional devices.

gateway

A host system that provides access between or among systems.

IBD

See Integrated Boot Device (IBD).

in-band signaling

The signals used to operate the communications channel. They share the same physical channel as the information or user data in the channel.

Integrated Boot Device (IBD)

Banks of memory in routers for storing configuration files.

Integrated Services Digital Network (ISDN)

An all-digital telecommunications technology that upgrades an ordinary telephone network using analog technology to an all-digital, end-to-end network. In ISDN, equipment is able to switch and transport all types of information, such as voice, data, and video.

interfaces

Logical entities that represent sources and destinations for packets. The router routes packets between interfaces not between devices. Some devices can support multiple interfaces. Every interface must use at least one device to physically transport packets.

Internet Protocol (IP)

The internetworking protocol that forms the basis of the Internet.

Internet Service Provider (ISP)

An organization providing access to the Internet. Examples of ISPs include NetCom, PSInet, Pipex, EUnet, and UUNET.

IP

See Internet Protocol (IP).

ISDN

See Integrated Services Digital Network (ISDN).

ISP

See Internet Service Provider (ISP).

LAN

See Local Area Network (LAN).

Light-Emitting Diode (LED)

A miniature low-voltage light source used for status lights because it emits light with no significant amount of heat.

LED

See Light-Emitting Diode (LED).

Local Area Network (LAN)

Any physical network technology that operates at high speed over short distances. For example, Ethernet.

mask

Determines which bits are used for the network part of an IP address, as well as which bits are used for the node part of an IP address.

Maximum Receive Unit (MRU)

Sets the maximum size of the information field within a packet.

MP

See Multilink Point-to-Point Protocol (MP).

MRU

See Maximum Receive Unit (MRU).

Multilink Point-to-Point Protocol (MP)

Combines two 64 Kbps B channels to provide bandwidth up to
128 Kbps.

multipoint connection

Two or more ISDN devices share an ISDN line.

Network Termination 1 (NT1)

The termination point of the ISDN system. It is the physical and electrical termination function of ISDN on the end-user's side of the ISDN connection. Without an NT1, ISDN cannot work. It is an interface between the S/T and U reference points and defines communication between functional devices.

NT1

See Network Termination 1 (NT1).

out-of-band signaling

The signals used to operate the communications channel are separate from the user's data channel. ISDN uses out-of-band signaling via the D channel.

PAP

See Password Authentication Protocol (PAP).

Password Authentication Protocol (PAP)

One of two authentication protocols (PAP and CHAP) used by OpenROUTE Networks routers. PAP requires a password from a connecting router before the local router can receive data from that router. If the password is accepted, communication between the the local router and the connecting router continues; if the password is not accepted, the communication line is closed.

PBX

See Private Branch Exchange (PBX).

Ping

A utility for testing whether a connection is up and running. It sends a packet out. If there is a response, the connection is okay.

Plain Old Telephone Service (POTS)

Transmits analog information through one channel. It is not ISDN.

point-to-point connections

One ISDN device is on an ISDN line.

POST

See Power On Self Test (POST).

POTS

See Plain Old Telephone Service (POTS).

Power On Self Test (POST)

Occurs when powering up the router. Takes from 10-30 seconds, depending on the size of the router's memory.

PRI

See Primary Rate Interface (PRI).

Primary Rate Interface (PRI)

An access interface used by businesses with large data needs or with the need to set up their own local phone system. It provides a fast connection to the telephone company. In North America and Japan, the most common PRI has 23 64 Kbps B channels and one 64 Kbps D channel (23B+D). In Europe, the most common PRI is 30 64 Kbps B channels, and one 64 Kbps D channel (30B+D).

Private Branch Exchange (PBX)

A telecommunications switch at the customer's site that typically handles the internal telecommunications needs of a large organization.

protocols

Rules governing communication between devices in a network.

provisioning

The special requirements for each piece of equipment that you need to tell your telephone company about when you order ISDN services.

reference points

Device-to-device interfaces in an ISDN topology, such as R, S/T, and U.

R reference point

Located on an ISDN between non-ISDN Terminal Equipment (TE2) and a Terminal Adapter (TA).

Service Profile Identifier (SPID)

An alphanumeric identifier that identifies the service capabilities of an ISDN device. The telephone company assigns this number.

Setup Utility

A Microsoft Windows-based graphical configurator shipped with your OpenROUTE Networks router.

Simple Network Management Protocol (SNMP)

Protocol used to monitor routers and attached networks. Information on devices managed is defined and stored in the application's Management Information Base (MIB).

SNMP

See Simple Network Management Protocol (SNMP).

SPID

See Service Profile Identifier (SPID).

static route

Route that you manually configure.

S/T reference point

Located on an ISDN between ISDN user equipment and Network Termination (NT1) equipment.

switch

Equipment, provided by the telephone company, that connects users on a telecommunications network. Every user has a dedicated connection to the nearest switch and every switch has access to trunk lines that enable calling beyond the local area. The switch determines how many ISDN devices you can handle, as well as how many different configuration options.

switching

The process of interconnecting two devices on a network so that they can communicate with each other. The switch determines how many ISDN devices you can handle and different configuration options.

TA

See Terminal Adapter (TA).

TE

See Terminal Equipment.

TEI

See Terminal End-point Identifier (TEI).

TE1

See Terminal Equipment 1 (TE1).

TE2

See Terminal Equipment 2 (TE2).

Telnet

Attaches your system to a remote router or a remote host.

Terminal Adapter (TA)

Converts some other form of communication to ISDN to allow non-ISDN devices to work with ISDN.

Terminal End-point Identifier (TEI)

An identifier provided by the telephone company that identifies terminal equipment on an ISDN interface.

Terminal Equipment

Any device you have that is connected to an ISDN.

Terminal Equipment 1 (TE1)

Any ISDN-ready device that connects directly to ISDN. For example, a digital phone or a GT 70 Series router.

Terminal Equipment 2 (TE2)

Device, such as a PC or FAX machine, that is not capable of connecting to ISDN without using the Terminal Adapter (TA). The combination of a TE2 and a TA has the same functionality as a TE1.

U reference point

Located on an ISDN between NT1 equipment and an ISDN central office.

user list

Users have various access privileges to the use of the router, such as to display or modify router configuration. This list is used for router administration.

Wide Area Network (WAN)

Any physical network technology that spans large geographic distances. For example, the Internet.