network architecture layout designed and constructed by: vicki kertz
TRANSCRIPT
Network ArchitectureNetwork Architecture
Layout designed and constructed by:
Vicki Kertz
TOPOLOGIESTOPOLOGIES
BusBus
RingRing
StarStar
HybridHybrid
Enterprise-wide Enterprise-wide
WANWAN
BusBus
a central cable that a central cable that connects all connects all devicesdevices on a on a local-area network local-area network
RingRing
Each node is Each node is connected to the two connected to the two nearest nodes so that nearest nodes so that the entire network the entire network forms a circle.forms a circle.
StarStar
Each Each nodenode (file (file server, workstations, server, workstations, and peripherals) and peripherals) connected directly to connected directly to a central network a central network hubhub or or concentratorconcentrator
HybridsHybrids
Star-wired RingStar-wired Ring
Star-wired BusStar-wired Bus
Daisy-chainedDaisy-chained
Hierarchical Hierarchical
Enterprise -wideEnterprise -wide Backbone Networks Backbone Networks – cabling that– cabling that connects connects
the hubs, switches and routersthe hubs, switches and routers Serial Serial – simplest; two or more connected by a single – simplest; two or more connected by a single
cablecable Distributed Distributed – number of hubs connected to a series – number of hubs connected to a series
of central hubs in a hierarchyof central hubs in a hierarchy Collapsed Collapsed – a router or switch as the single central – a router or switch as the single central
connection point for multiple subnetworksconnection point for multiple subnetworks ParallelParallel – robust; more than one connection from the – robust; more than one connection from the
central router to each network segmentcentral router to each network segment
Mesh Mesh – routers interconnected with others and – routers interconnected with others and at least two pathways connecting each routerat least two pathways connecting each router
WANWAN
Peer-to-peerPeer-to-peer
RingRing
StarStar
MeshMesh
TieredTiered
Network Transport SystemsNetwork Transport Systems
The logical topology is the way that the The logical topology is the way that the signals act on the network media, or the signals act on the network media, or the way that the data passes through the way that the data passes through the network from one device to the next network from one device to the next without regard to the physical without regard to the physical interconnection of the devices. interconnection of the devices.
SwitchingSwitching Circuit -Circuit - A type of communications in which a A type of communications in which a dedicateddedicated channelchannel
(or (or circuitcircuit) is established for the duration of a transmission. ) is established for the duration of a transmission.
Message – establishes a connection between two devices, Message – establishes a connection between two devices,
transfers the info to the 2transfers the info to the 2ndnd device, then breaks the connection. device, then breaks the connection.
Packet - Refers to Packet - Refers to protocolsprotocols in which messages are divided into in which messages are divided into
packetspackets before they are sent. Each packet is then transmitted before they are sent. Each packet is then transmitted
individually and can even follow different routes to its destination. individually and can even follow different routes to its destination.
Once all the packets forming a message arrive at the destination, Once all the packets forming a message arrive at the destination,
they are recompiled into the original message. they are recompiled into the original message.
CSMA/CDCSMA/CD
Carrier Sense Multiple Access with Carrier Sense Multiple Access with Collision DetectionCollision Detection
Set of rules determining how Set of rules determining how networknetwork devicesdevices respond when two devices respond when two devices attempt to use a attempt to use a data channeldata channel simultaneously (called a simultaneously (called a collisioncollision) )
Standard Standard EthernetEthernet networks use networks use CSMA/CD CSMA/CD
Ethernet VersionsEthernet Versions
10Base2 10Base2 10Base510Base5 10BaseT10BaseT 100BaseT100BaseT 100BaseTX100BaseTX 100BaseVG100BaseVG 1000BaseX1000BaseX
10Base210Base2 The 10Base-2 standard (also called The 10Base-2 standard (also called ThinnetThinnet) uses 50 ) uses 50
ohm ohm coaxial cablecoaxial cable (RG-58 A/U) with maximum lengths of (RG-58 A/U) with maximum lengths of 185 meters.185 meters.
Ethernet over coaxial cable with a maximum distance of Ethernet over coaxial cable with a maximum distance of 185 meters. Also referred to as 185 meters. Also referred to as Thin EthernetThin Ethernet or or ThinnetThinnet or or ThinwireThinwire. .
10Base510Base5 The original cabling standard for The original cabling standard for EthernetEthernet that that
uses uses coaxial cablescoaxial cables. The name derives from the . The name derives from the fact that the maximum data transfer speed is fact that the maximum data transfer speed is 1010 MbpsMbps, it uses , it uses basebaseband transmissionband transmission, and the , and the maximum length of cables is maximum length of cables is 5500 meters. 00 meters.
10BaseT10BaseT 10 10 MbpsMbps basebandbaseband
100BaseT100BaseT A A networkingnetworking standardstandard that supports that supports
data transfer ratesdata transfer rates up to 100 up to 100 MbpsMbps (100 (100 megabits per second). 100BASE-T is based on megabits per second). 100BASE-T is based on the older the older EthernetEthernet standard. Because it is 10 standard. Because it is 10 times faster than Ethernet, it is often referred to times faster than Ethernet, it is often referred to as as Fast Ethernet.Fast Ethernet. (100BaseTX & 100BaseT4) (100BaseTX & 100BaseT4)
1000BaseT1000BaseT
A specification for Gigabit A specification for Gigabit EthernetEthernet over copper wire over copper wire
(IEEE Std. 802.3ab). The standard defines 1 Gb/s (IEEE Std. 802.3ab). The standard defines 1 Gb/s
data transfer over distances of up to 100 meters data transfer over distances of up to 100 meters
using four pairs of CAT-5 balanced copper cabling using four pairs of CAT-5 balanced copper cabling
and a 5-level coding scheme. and a 5-level coding scheme.
Other 1000Base-T benefits include compatibility Other 1000Base-T benefits include compatibility
with existing network with existing network protocolsprotocols (i.e. IP, IPX, (i.e. IP, IPX,
AppleTalk), existing applications, Network Operating AppleTalk), existing applications, Network Operating
Systems, Systems, network managementnetwork management platforms and platforms and
applications.applications.
Switched EthernetSwitched Ethernet
An An EthernetEthernet LANLAN that uses that uses switchesswitches to connect to connect individual individual hostshosts or or segmentssegments. In the case of . In the case of individual hosts, the switch replaces the individual hosts, the switch replaces the repeaterrepeater and effectively gives the device full 10 and effectively gives the device full 10 MbpsMbps bandwidth (or 100 Mbps for bandwidth (or 100 Mbps for Fast EthernetFast Ethernet) to the ) to the rest of the network. rest of the network.
Ethernet Frame TypesEthernet Frame Types
802.2802.2
802.3802.3
Ethernet IIEthernet II
Ethernet SNAPEthernet SNAP
802.2802.2
General standard for the data link layer in the General standard for the data link layer in the OSI Reference ModelOSI Reference Model. The IEEE divides this . The IEEE divides this layer into two sub layers -- the layer into two sub layers -- the logical link control logical link control (LLC) layer (LLC) layer and the and the media access control (MAC) layermedia access control (MAC) layer. .
Preamble8 bytes
Destinationaddress
Sourceaddress
Length2
bytesLLC
46 – 1500bytes
FCS4 bytes
DSAP1 byte
SSAP1 byte
ControlField
1 byte
802.3802.3
Defines the MAC layer for Defines the MAC layer for bus networksbus networks that use that use CSMA/CDCSMA/CD. This is the basis of the . This is the basis of the EthernetEthernet standard standard
Preamble7 bytes
Destinationaddress
Sourceaddress
46 – 1500bytes
LLCFCS
4 bytes
Length2
bytesSFC
1 byte
MauMau
Multistation Access UnitMultistation Access Unit a a token-ring networktoken-ring network device that physically device that physically
connects network computers in a connects network computers in a star topologystar topology while retaining the logical ring structure while retaining the logical ring structure
MAU is a special type of MAU is a special type of hubhub One of the problems with the token-ring topology One of the problems with the token-ring topology
is that a single non-operating is that a single non-operating nodenode can break can break the ring. The MAU solves this problem because the ring. The MAU solves this problem because it has the ability to short out non-operating it has the ability to short out non-operating nodes and maintain the ring structure nodes and maintain the ring structure
Design Considerations for Design Considerations for Token Ring NetworksToken Ring Networks
CablingCabling
Connectivity devicesConnectivity devices
# of stations# of stations
SpeedSpeed
ScalabilityScalability
TopologyTopology
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