User guide

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MTPSR3-100 User Guide
Frame Relay Implementors Forum: A group of companies
supporting a common specification for frame relay connection to
link customer premises equipment to telco network equipment.
Their specification supports ANSI frame relay specs and defines
extensions such as local management.
Frame Relay Access Device (FRAD): A piece of equipment that
acts as a concentrator or frame assembler/dissassembler that
can support multiple protocols and provide basic “routing”
functions.
G
Gateway: 1. A functional unit that interconnects two computer
networks with different network architectures. A gateway
connects networks or systems of different architectures. A bridge
interconnects networks or systems with the same or similar
architectures. 2. A network that connects hosts.
Graphical User Interface (GUI): A type of computer interface
consisting of a visual metaphor of a real-world scene, often of a
desktop. Within that scene are icons, representing actual objects,
that the user can access and manipulate with a pointing device.
H
Handshaking: A process that two modems go through at the
time of call setup to establish synchronization over the data
communications link. It is a synchronization and negotiation
process accomplished by the exchange of predefined, mutually
recognized control codes.
High-level Data Link Control (HDLC): An ISO standard, bit-
oriented data communications protocol that provides nearly
error-free data transfers.
I
Hexadecimal: A base 16 numbering system used to represent
binary values. Hex uses the numbers 0-9 and the letters A-F:
usually notated by an “h” (e.g., “4CF h”, read “four charley fox,
hex”). The result is that one hex digit represents a 4-bit value.
Implicit congestion management: A method of informing the
terminal that the network is busy. This method relies on the end-
system protocol to detect and fix the congestion problem. (TCP/
IP is an example of a protocol using only implicit congestion
management.) See also “explicit congestion management”.
In-band: Refers to the type of signalling over the conversion
path on an ISDN call. Contrast “out-of-band”.
Insufficient Ones: A T1 error condition that is logged when
fewer than one 1 in 16 0s or less than 12.5 % average 1s density
is received.
Inter Exchange Carrier (IEC): The long distance company (LE)
who’s central office provides the point of reference for T1 access.
Any common carrier authorized by the FCC to carry customer
transmissions between LATAs.
Internet: Refers to the computer network of many millions of
university, government and private users around the world. Each
user has a unique Internet Address.
Internet Address (IP Address): A unique 32-bit address for a
specific TCP/IP host on a network. Normally printed in dotted
decimal format (e.g., 129.128.44.227).
Internet Protocol (IP): A protocol used to route data from its
source to its destination in an Internet environment. The Internet
Protocol was designed to connect local area networks. Although
there are many protocols that do this, IP refers to the global
system of interconnecting computers. It is a highly distributed
protocol (each machine only worries about sending data to the
next step in the route).
Internetwork Packet Exchange (IPX): A NetWare
communications protocol used to route messages from one node
to another. IPX packets include network addresses and can be
routed from one network to another. An IPX packet can
occasionally get lost when crossing networks, thus IPX does not
guarantee delivery of a complete message. Either the application
has to provide that control, or NetWare’s SPX protocol must be
used.
Inter-operable: Devices from different vendors that can
exchange information using a standard’s base protocol.
I/O Addresses: Locations within the I/O address space of your
computer used by a device, such as an expansion card, a serial
port, or an internal modem. The address is used for
communication between software and a device.
IRQ Level (Interrupt Request Level): The notification a
processor receives when another portion of the computer’s
hardware requires its attention. IRQs are numbered so that the
device issuing the IRQ can be identified, and so IRQs can be
prioritized.
ISA (Industry Standards Architecture) (pronounced “ice a”):
The classic 8 or 16-bit architecture introduced with IBM’s PC-AT
computer.
ISDN (Integrated Services Digital Network): An International
telecommunications standard for transmitting voice, video and
data over a digital communications line. ISDN is a worldwide
telecommunications service that uses digital transmission and
switching technology to support voice and digital data
communications. Frame relay was partially based on ISDN’s data
link layer protocol (LAPD). Frame relay can be used to transmit
across ISDN services offering circuit-switched connection at 64K
bps and higher speeds. Contrast Public Switched Telephone
Network (PSTN).
ITU-TSS (formerly CCITT): International Telecommunications
Union-Telecommunications Sector; the United Nations
organization that prepares standards (“Recommendations”) for
resolving communications issues and problems.
J
No Entries.
K
Key Telephone System (KTS): Phone devices with multiple
buttons that let you select incoming or outgoing CO phone lines
directly. Similar in operation to a PBX, except with a KTS you
don’t have to dial a “9” for a call outside the building.
Key Service Unit (KSU): A small device containing the switching
electronics for a business key telephone system (KTS).
Key Set: A telephone set with several buttons for call holding,
line pickup, intercom, autodialing, etc. Also called a touchtone
phone (Ericsson) and a KTS (Key Telephone Set).