Download 4 Kyung Hee University Line configuration (cont`d)

Basic Concepts
Prof. Choong Seon HONG
Kyung Hee
University
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Basic Concepts
 Five general concepts provide the basis for the relationship
between the communicating devices.
Line configuration
Topology
Transmission mode
Categories of Networks
Internetworks
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University
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2.1 회선구성 (Line configuration)
~ refers to the way two or more communication devices attach
to a link
~ defines the attachment of communication devices to a link
Line configuration
Point-to-point
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University
Multipiont
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Line configuration (cont’d)
점-대-점(Point-to-point)
~ provides
a dedicated link between two devices.
다중 점(Multipoint) : multidrop
~ is
configuration in which more than two specific devices
share a single link
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University
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Line configuration (cont’d)
 점-대-점 회선 구성
Link
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University
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Line configuration (cont’d)
 점-대-점 회선 구성
Link
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University
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Line configuration (cont’d)
 점-대-점 회선 구성
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University
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Line configuration (cont’d)
 다중 점 회선 구성
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University
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접속형태(Topology)
~ refers to the way a network is laid out, either physically
or logically
~ defines the physical or logical arrangement of link in a
network
A consideration when choosing a topology is the
relative status of the devices to be linked.
peer-to-peer : the devices share the link equally(ring, mesh)
primary-secondary : one device controls traffic and the others
must transmit through it (star, tree)
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University
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접속형태 분류(Categories of topology)
Topology
Mesh
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University
Star
Tree
Bus
Ring
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그물형 (Mesh)
Every device has a dedicated point-to-point link to
every other device.
A fully connected mesh network therefore has n(n-1)/2
physical channels to link n devices.
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University
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그물형(cont’d)
Mesh topology
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University
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Mesh (cont’d)
Advantages
The use of dedicated links guarantees that each
connection can carry its data load.
Mesh topology is robust.
Privacy and security.
Point-to-point links make fault identification and fault
isolation easy.
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University
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그물형 (cont’d)
Disadvantages
~ are related to the amount of cabling and the number
of I/O ports
because every device must be connected to every
other device, installation and reconfiguration are
difficult
the sheer bulk of the wiring can be greater than the
available space(in walls, ceiling, or floors) can
accommodate
the hardware required to connect each link (I/O port
and cable) can be prohibitively expensive
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University
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스타형 (Star : 성형)
Each device has a dedicated point-to-point link only to
a central controller, usually called a hub
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University
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Star (cont’d)
Star topology
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University
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Star (cont’d)
Advantage
Each device needs only one link and one I/O port to
connect it to any number of others (easy to install
and reconfigure)
Robustness

if one link fails, only that link is affected
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University
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트리형 (Tree)
is a variation of a star
active hub(central hub)
~ contains a repeater, which is a hardware device
that generates the received bit patterns before
sending them out
passive hub
~ provides a simple physical connection between
the attached devices
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University
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Tree (cont’d)
Tree topology
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University
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Tree (cont’d)
Advantage & Disadvantage
are generally the same as those of a star
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University
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버스형 (Bus)
is multipoint. One long cable acts as a backbone to link
all the devices in the network
Nodes are connected to the bus cable by drop lines and
taps
drop line
~ is a connection running between the device and the main
cable
tap
~ is a connector either splices into the main cable or
punctures the sheathing of a cable to create a contact with
the metallic core
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University
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Bus (cont’d)
Bus topology
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University
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Bus (cont’d)
Advantages
~ include ease of installation
Disadvantages
~ include difficult reconfiguration and fault isolation
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University
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링형 (Ring)
Each device has a dedicated point-to-point line
configuration only with the two devices on either side
of it
Advantage
~ is relatively easy to install and reconfigure
~ fault isolation is simplified
Disadvantage
unidirectional traffic

break in the ring can disable the entire network
--> needs dual ring
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University
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Ring (cont’d)
Ring topology
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University
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혼합형(Hybrid topology)
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University
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2.3 전송모드(Transmission mode)
~ is used to define the direction of signal flow between two link
devices
 단방향(Simplex)
is unidirectional, as on a one-way street (keyboard, monitor)
 반이중(Half-Duplex)
each station can both transmit and receive, but not at the same
time
 전이중(Full-Duplex)
both stations can transmit and receive simultaneously
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University
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Transmission Mode (cont’d)
Transmission modes
Simplex
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University
Half-duplex Full-duplex
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Transmission Mode (cont’d)
단방향 (Simplex)
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University
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Transmission Mode (cont’d)
반이중(Half-Duplex)
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University
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Transmission Mode (cont’d)
전이중(Full-Duplex)
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University
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2.4 네트워크 분류 (Categories of Networks)
three primary categories
근거리 통신망 (LAN)
도시 통신망 (MAN)
광역 통신망 (WAN)
size, ownership, distance it cover, physical architecture
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University
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Categories of Networks (cont’d)
Network
Local area networks
(LAN)
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University
Metropolitan area network
(MAN)
Wide area network
(WAN)
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Categories of Networks (cont’d)
LAN(Local Area Networks)
~ is usually privately owned and links the devices in a
single office, building or campus
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University
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Categories of Networks (cont’d)
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University
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Categories of Networks (cont’d)
MAN(Metropolitan Area Networks)
~ is designed to extend over an entire city
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University
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Categories of Networks (cont’d)
WAN(Wide Area networks)
~ provides long-distance transmission of data, voice,
image, and video information over large
geographical areas that may comprise a country, a
continent, or even the whole world
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University
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Categories of Networks (cont’d)
WAN
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University
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2.5 네트워크간 네트워크 (Internetworks)
~ is an interconnection of networks by the use of
internetworking device(router and gateway)
cf.
internet: an interconnection of networks
Internet: a specific worldwide network
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University
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Internetworks (cont’d)
Internetwork (internet)
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University
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