Transcript terminologies - Faculty of Computer Science and Information

TERMINOLOGIES
26TH
GROUP 15
JANUARY, 2005
Group Members :

AHMAD FAKHRI BIN AB. NASIR
WET 020003

MOHD FADZLY BIN MD YASIN
WET 020085

NURUL IZA BT MOHD ZAIN
WET 020136

TENGKU AZLAN BIN RAJA MAMAT
WET 020180

AMIR RAMZANI BIN BORHAN
WET 040002

NORHASLINDA ROSLE
WET 040085
TENGKU AZLAN BIN RAJA MAMAT
WET 020180
TERM
DEFINITION
ATM Adaptation Layer
(AAL)
-A collection of standardized protocols that adapt
user traffic to the cell format.
-The AAL is subdivided into the Convergence Sub
layer (CS) and the Segmentation and
Reassembly (SAR) sub layer.
-There are currently 4 types of AALs: AAL1, AAL2,
AAL3/4 and AAL5 to support the various AAL
service classes
Asynchronous
Transfer Mode (ATM)
-A transfer mode in which the information is
organized into 53 octet PDUs called cells.
-It is asynchronous in the sense that the
recurrence of cells containing information from an
individual user is not necessarily periodic.
Bandwidth
-The amount of data that can be transmitted in a
fixed amount of time.
Banyan/Delta
Switching
- A concept of an interconnection of stages of
switching elements
B-ISDN – Broadband
Integrated Services
Digital Network
- A protocol platform, introduced by ITU-T, to
support the integrated, high-speed transmission of
data, audio and video in a seamless fashion.
- ATM emerged as a suitable transport standard.
The B-ISDN architecture model has been adopted
by ATM, which is referred as the ATM reference
model.
Bridge
- A device that connects two local-area networks
(LANs), or two segments of the same LAN that
use the same protocol, such as Ethernet or
Token-Ring.
Broadband
- A type of data transmission in which a single
medium (wire) can carry several channels at
once.
Broadcast
- Consists of a single data packet that is copied
and sent to all nodes on the network
Buffer
-A temporary storage area, usually in RAM to act
as a holding area, enabling the CPU to
manipulate data before transferring it to a device.
Bus
-Collection of wires through which data is
transmitted from one part of a computer to
another.
Burst tolerance
- A traffic parameter that specifies the maximum
number of cells which will be accepted at the
Peak Cell Rate (PCR) on an ATM connection.
Cell
-The 53-byte basic information unit consists of a
5-byte ATM header and a 48-byte ATM payload,
which contains the user data.
NURUL IZA BT MOHD ZAIN
WET 020136
Congestion control
-Mechanisms that control traffic flow.
Connection
Admission Control
-Set of actions taken by the network during the
call set-up phase to determine whether a
connection request can be accepted or should
be rejected.
Crossbar Switch
Database
-A simple matrix-like space division technique
that physically interconnects any of the N inputs
to any of the N outputs at crosspoints
-A collection of information organized in such a
way that a computer program can quickly select
desired pieces of data.
Explicit Forward
Congestion
Indication (EFCI)
-A 1-bit field in the PTI that contains
information whether congestion at an
intermediate node has been experienced.
End System
Identifier (ESI)
-The 6-octet field within the ATM NSAP format
address, which identifies an end system.
Frame Discard (FD)
-A procedure for discarding cells related to one
user frame to minimize the impact of
congestion.
Forward Explicit
Congestion
Notification (FECN)
-An indicator bit in the Frame Relay header to
notify the destination of traffic that the virtual
circuit is passing through a congested switch.
Feedback control
-Actions taken by the network and by the endsystems to regulate the traffic submitted on
ATM connections according to the state of
network elements.
Fiber optic
-Cable with glass and plastic medium.
-Uses light ( laser ) to transmit data.
Flow control
-Congestion control mechanism that results in an
ATM system implementing flow control.
Frame Relay
-An efficient packet switching technology to
provide reliable packet delivery over virtual
circuits.
Generic Flow Control
(GFC)
-A four-bit field within the ATM cell header which
may be used to identify whether or not an ATM
system implements congestion control.
Header (Cell header)
-The ATM cell header is a 5-byte header that
contains the following fields:
• Generic Flow Control (GFC)
•4 bits Virtual Path Identifier (VPI)
•8 bits Virtual Channel Identifier (VCI)
•16 bits Payload Type (PT)
•3 bits Cell Loss Priority (CLP)
•1 bit Header Error Check (HEC)
•8 bit CRC computed over the previous four
octets.
Header Error Check
(HEC)
-A one-byte field within the ATM cell header
providing for error detection.
-If an error is detected, the cell will be discarded
before undergoing reassembly.
AHMAD FAKHRI BIN AB. NASIR
WET 020003
Hub
- Layer 1 device also called multi-port repeater
IETF - Internet
Engineering Task
Force
-A body, which was initially responsible for
developing specification, required for the
interoperable implementation of IP.
Interface
-A boundary across which two independent
systems meet and act on or communicate with
each other.
Local Area Network
(LAN)
-A computer network that spans a relatively
small area.
-Most LANs are confined to a single building or
group of buildings.
LAN Emulation
(LANE)
-LANE is a single Virtual LAN (VLAN)
consisting of traditional LAN segments and an
emulated LAN (ELAN) segment across the ATM
network.
Leaky Bucket
-A flow control algorithm, where cells are
monitored to check whether they comply with
the established connection parameters.
-Non-conforming cells are either tagged or
dropped from the network.
-The analogy is taken from a bucket with a hole
in its bottom that allows the fluid to flow out at a
certain rate.
Line Emulation Client
(LEC)
-Located in the ATM end system, to maintain
address resolution tables and to forward data
traffic.
LAN Emulation
Server (LES)
-A server functions within LANE providing for
LEC registration, MAC to ATM address
resolution and security management of a
VLAN.
Local Management
Interface (LMI)
-An ITU-T defined interface to provide an ATM
end system user with network management
information.
Metropolitan Area
Network (MAN)
-A network that provides regional connectivity
within a metropolitan area (such as city).
MANs are categorized between LANs and
WANs.
Multicast
Multistage Switching
-To transmit a single message to a select group
of recipients.
-Similar concept to the crossbar switch
technique with a more tree-like structure to
reduce the N squared crosspoints requirement
yielding a more economical arrangement
AMIR RAMZANI BIN BORHAN
WET 040002
Network Resource
Management (NRM)
-The allocation of network resources in order to
separate traffic flows according to different
service characteristics to maintain network
performance and to optimize resource utilization.
Network Interface
Card (NIC)
-The hardware communication interface (circuit
board) required for the DTE (workstation, PC) to
access the network.
Network Node
Interface / Network-toNetwork Interface
(NNI)
-ITU-T specified standard interface between
nodes within the same network.
-The ATM forum distinguishes between two
standards, one for private networks called P-NNI
and one for public networks known as public
NNI.
Node
-A processing location that can be a computer or
some other device, such as a printer.
Packet
-A piece of a message transmitted over a
packet-switching network.
Packet switching
-Protocols in which messages are divided into
packets before they are sent.
-Each packet is then transmitted individually
and can even follow different routes to its
destination.
-Once all the packets forming a message arrive
at the destination, they are recompiled into the
original message.
Payload
-The 48-byte segment
containing user data.
Peak Cell Rate (PCR)
-A traffic parameter that characterized the
source and gives the maximum rate at which
cells can be transmitted.
of
the
ATM
cell
Physical layer
-The bottom layer of the ATM, it is subdivided into
two sublayers:
•Transmission Convergence (TC)
•Physical Medium (PM).
-It provides ATM cell transmission over the
physical interfaces that interconnect the ATM
devices.
Private NetworkNetwork Interface
(PNNI)
-The interswitch interface within a private ATM
domain.
-The PNNI trunking protocol providing for
hierarchical ATM-layer routing and QoS support.
Preventive
-Prevent congestion from ever happening in the
first place, by reserving resources
Protocol
-An agreed-upon format for transmitting data
between two devices.
Permanent Virtual
Circuit (PVC)
-A virtual connection established by the
network management between an origin and a
destination that can be left up permanently.
Permanent Virtual
Path (PVP)
-A term to describe a set of grouped together
permanent virtual channels (PVCs) that exist
between two cross points.
Quality Of Service
(QoS)
-A group of service classes defined by the ATM
forum in terms of different QoS parameters.
NORHASLINDA ROSLE
WET 040085
Reactive
-Feedback-based
-Attempt to detect congestion, or the onset of
congestion, and take action to resolve the problem
before things get worse
-The hosts and routers respond to congestion
AFTER it occurs and then attempt to stop it
Ring topology
-Connects one host to the next and the last host to
the first
Routing
-The process of moving a packet of data from source
to destination.
Service Access
Point (SAP)
-Reference point between the networking
stack and applications within an end system.
Segmentation And
Reassembly (SAR)
-Segments the information frames into cells
at the source and reassembled these cells
back into information frames at the
destination.
Segmentation And
Reassembly
Protocol Data Unit
-The 48 octet PDU that the SAR sublayer
exchanged with the ATM layer comprised of
the SAR-PDU payload and any control
information that the SAR sublayer might add.
Sustainable Cell
Rate (SCR)
-A traffic parameter that characterized a
bursty source and specified the maximum
average rate at which cells can be sent over
a given virtual connection (VC).
Server
-A computer or device on a network that
manages network resources.
Shared Bus Switch
-Approach utilizes a bus or dual bus architecture
to switch cell traffic.
-Frame based traffic can be converted to ATM
cells and vice versa
Shared Memory
Switch
- A technique that uses a common memory for
the storage of cells and switching fabric.
Source
-A place from which data is taken or the node on
a network from which data is sent to its
destination.
Star topology
-Connects all cables to a central point ( Hub or
Switch )
Switched Virtual Path
Connection (SVPC)
-A virtual path connection that is set up and turn
down dynamically through signaling procedures.
Switch
-A device that filters and forwards packets
between LAN segments operates at the data link
layer (layer 2) and sometimes the network layer
(layer 3) of OSI Model
Token bucket
-It accumulates tokens at a certain fixed rate;
once there are sufficiently many tokens, the
packet currently waiting in the packet buffer
enters the network, and removes its tokens from
the bucket.
MOHD FADZLY BIN MD YASIN
WET 020085
Token frame
-Function as a placeholder and reservation
frame
Token passing
-Controls network access by passing an
electronic token sequentially to each host
Traffic
-The load on a communications device or
system.
Traffic shaping
-A method for smoothing the bursty traffic rate
that might arrive on an access virtual circuit.
Unicast
-A single packet is sent from the source to a
destination on a network.
User-to-Network
Interface (UNI)
- The interface between the ATM end user and a
private ATM switch.
-It also can represent the interface between a
private ATM switch and the public carrier ATM
network.
Virtual Connection
(VC)
-A connection established between end users,
where packets are forwarded along the same
path and bandwidth is not permanently allocated
until it is used.
Virtual Channel
Connection (VCC)
-An end to end connection consisting of a
concatenation of two or more Virtual Channels
between two end points.
Video
-Recording, manipulating, and displaying moving
images, especially in a format that can be
presented on a television.
Virtual Channel
Identifier (VCI)
Virtual Path (VP)
Switch
-Identifies a particular VC link for a given VP
connection
-A bundle of Vitrual Channel (VC) links, and all
the VC links in the bundle have the same
endpoints, so that a VC link is equivalent to a VP
connection
Virtual Path
Connection (VPC)
Switch
-A group of logical connections between one
ATM switch port and another ATM switch port.
-Provided for the purpose of user-user, usernetwork, network-network information transfer.
Virtual Path Identifier
(VPI)
-Identifies the virtual path (a bundle of virtual
channels that have the same endpoint) to which
the cell belongs as it travels through an ATM
network.
Wide Area Network
(WAN)
-A network that typically spans nationwide
distances and usually utilized public telephone
networks.