IBM 2220 Nways 300, Service Manual

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TDM. Time division multiplexing.
TE. Terminal equipment.
Telnet. In TCP/IP, an application protocol that allows a
user at one site to access a remote system as if the
display station were locally attached. Telnet uses the
Transmission Control Protocol (TCP) as the underlying
protocol.
time division multiplexing (TDM). The process of
breaking the bandwidth on a communication line into a
number of channels, possibly of different size.
TME. Tivoli Management Environment.
TMN. Telecommunication Management Network.
TPA. Trunk or port adapter.
Transmission Control Protocol/ Internet Protocol
(TCP/IP). A set of communication protocols that
support peer-to-peer connections over both local and
wide area networks.
transport services. Functions that are performed by a
trunk adapter of an Nways Switch to:
Ÿ
Support the attachment of trunk lines
Ÿ
Maximize bandwidth utilization
Ÿ
Guarantee the quality of service of a connection
Ÿ
Transfer packets between Nways Switches
Ÿ
Manage logical queues and schedule transmission.
trunk. See logical trunk.
trunk adapter. In an Nways Switch, a module that
provides transport services to one or more trunk lines.
Each trunk adapter is associated with a line interface
coupler (LIC).
trunk line. In a 2220 network, a high-speed line
connecting two Nways Switches. It can be, for example,
a copper cable, optical fiber, or radio wave guide and
can be leased from telecommunication companies.
UBR. Unspecified bit rate. A best effort service with no
quality commitment.
UNI. User network interface.
UPC. Usage parameter control.
URL. Uniform resource locator.
user network interface (UNI). A standardized
interface between a user and a communication network.
UTC. Universal time, coordinated.
UUS. User-user signaling.
VBR. Variable bit rate.
VC. Virtual channel.
VCC. Virtual channel connection.
VCI. Virtual channel identifier.
VCN. Virtual circuit number.
virtual channel (VC). In ATM, a unidirectional route
between two ATM devices. Virtual channels always
come in pairs, one in each direction. They follow virtual
paths.
virtual channel connection (VCC). In ATM, a
unidirectional connection established over a virtual
channel. Virtual channel connections always come in
pairs, one VCC in each direction.
virtual channel identifier (VCI). In ATM, the unique
numeric tag that identifies every channel. It is defined
by a 16-bit field in the ATM cell header.
virtual connection. In frame relay, the return path of
an FR potential connection.
virtual path (VP). In ATM, a group of virtual channels
that are switched together as one unit. (Also called VC
service.)
virtual path connection (VPC). In ATM, a connection
established over a virtual path. Virtual path connections
always come in pairs, one VPC in each direction. (Also
called VP service.)
virtual path identifier (VPI). In ATM, an 8-bit field in
the ATM cell header that indicates the virtual path over
which the cell is to be routed.
voice server adapter (VSA). In an Nways Switch, a
module that supplies additional voice functions to voice
connections operating in pulse code modulation at
64 kbps. It can attach a voice server extension (VSE).
voice server extension (VSE). In an Nways Switch, a
module associated with a voice server adapter (VSA) to
supply voice functions to an extended number of PCM
voice connections.
VP. Virtual path.
VPC. Virtual path connection.
VPD. Vital product data.
VPI. Virtual path identifier.
VPN. Virtual private network.
Glossary
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