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Outlines Received due 13 March. 24 %. Homework. Review for Midterm on 1 March 2000 Research Paper Readings [11] “ATM Systems: What’s Next?” [12] “Long Distance LAN Interconnectivity”. MID-TERM. 1 Hour 15 minute Test Practice LAN/MAN problems on the Web Work 4 of 5 pages - PowerPoint PPT Presentation
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OutlinesReceived
due 13 March
OutlinesReceived
due 13 March24 %
HomeworkHomework Review for Midterm on 1 March 2000Review for Midterm on 1 March 2000 Research PaperResearch Paper ReadingsReadings
[11] “ATM Systems: What’s Next?”[11] “ATM Systems: What’s Next?”[12] “Long Distance LAN[12] “Long Distance LAN
Interconnectivity”Interconnectivity”
MID-TERMMID-TERM 1 Hour 15 minute Test 1 Hour 15 minute Test Practice LAN/MAN problems on the WebPractice LAN/MAN problems on the Web Work 4 of 5 pagesWork 4 of 5 pages Know the last midterm, 7 Layer ModelKnow the last midterm, 7 Layer Model Memory Dump in the space providedMemory Dump in the space provided Calculators are NOT allowedCalculators are NOT allowed
...Set up numerical problem for full credit...Set up numerical problem for full credit
IP over Frame RelayIP over Frame Relay
7 Application7 Application 6 Presentation6 Presentation 5 Session TCP5 Session TCP 4 Transport TCP4 Transport TCP 3 Network3 Network IPIP 2 Data Link2 Data Link Frame Relay Frame Relay 1 Physical1 Physical
Internet Service Provider BackboneInternet Service Provider Backbone
If you look closely atthe Router Trunks, you may find they are...
Router
TrunksLeased Line
Frame Relay is an ISP favoriteFrame Relay is an ISP favorite
... Frame Relay Virtual Circuits.
FR Switch
Trunks
ISP Router
Leased Line
FRPVC
Frame Relay as a Corporate Backbone...
Frame Relay as a Corporate Backbone...
More Secure than the InternetMore Secure than the Internet Can move a lot of data rapidly Can move a lot of data rapidly
(if you pay for proper CIR and burst rate)(if you pay for proper CIR and burst rate) Is marginal for moving time sensitive trafficIs marginal for moving time sensitive traffic Generally Cheaper for data than Leased LinesGenerally Cheaper for data than Leased Lines
Fewer access lines required Fewer access lines required Backbone has higher Carrying Capacity Backbone has higher Carrying Capacity
ATMATM OSI Layer 2 ProtocolOSI Layer 2 Protocol Uses Cell SwitchingUses Cell Switching
5 bytes overhead, 48 bytes traffic5 bytes overhead, 48 bytes traffic Capable of hauling all types of trafficCapable of hauling all types of traffic
(voice, data, & video) (voice, data, & video) Works at any speed, any distanceWorks at any speed, any distance Uses Virtual CircuitsUses Virtual Circuits
ATMis a
Compromise
ATMis a
Compromise
Consider ATM if...Consider ATM if...
Your network is moving mixed trafficYour network is moving mixed traffic You need sheer SPEEDYou need sheer SPEED You get a good deal $$$$You get a good deal $$$$
Connection RelationshipsConnection Relationships Virtual Channel: Virtual Channel:
Individual Service Component. Individual Service Component. Smallest switchable unit.Smallest switchable unit.
Virtual Path: Virtual Path: Group of Virtual Channels with sameGroup of Virtual Channels with same
endpoints & QoS requirementsendpoints & QoS requirements Backbone ATM switches: Switch VP’sBackbone ATM switches: Switch VP’s Edge ATM switches: Edge ATM switches:
Switch VC’s and VP’sSwitch VC’s and VP’s
Selected ATM ParametersSelected ATM Parameters
PCR: Peak Cell RatePCR: Peak Cell RateMaximum submission rateMaximum submission rate
SCR: Sustainable Cell RateSCR: Sustainable Cell RateAverage sustainable submission rateAverage sustainable submission rate
MCR: Minimum Cell RateMCR: Minimum Cell RateGuaranteed minimum delivery rateGuaranteed minimum delivery rate
CDV: Cell Delay VariabtionCDV: Cell Delay VariabtionVariability in cell inter-arrival timesVariability in cell inter-arrival times
ATM Classes of ServiceATM Classes of Service
Constant Bit Rate (CBR)Constant Bit Rate (CBR)Circuit Switched EmulationCircuit Switched Emulation Fixed rate voice or video Fixed rate voice or video
(compressed or uncompressed)(compressed or uncompressed) Leased LinesLeased Lines
Key Parameters: PCR & CDV (small)Key Parameters: PCR & CDV (small)
ATM Classes of ServiceATM Classes of Service
Variable Bit Rate - Real Time (VBR-RT)Variable Bit Rate - Real Time (VBR-RT)Interactive variable rate compressed Interactive variable rate compressed voice or videovoice or video TelephonyTelephony VideoconferencingVideoconferencing
Key Parameters: PCR, SCR, CDV (larger)Key Parameters: PCR, SCR, CDV (larger)
ATM Classes of ServiceATM Classes of Service
Variable Bit Rate - Non Real Time (VBR-NRT)Variable Bit Rate - Non Real Time (VBR-NRT)Non-interactive variable rate compressed voice Non-interactive variable rate compressed voice
or videoor video Broadcast RadioBroadcast Radio Broadcast TVBroadcast TV Could, and has been, used instead of ABR VC’sCould, and has been, used instead of ABR VC’s
Key Parameters: PCR, SCRKey Parameters: PCR, SCR
ATM Classes of ServiceATM Classes of Service Available Bit Rate (ABR)Available Bit Rate (ABR)
Data traffic needing some guaranteesData traffic needing some guarantees Interactive data trafficInteractive data traffic Frame Relay or ISP TrunksFrame Relay or ISP Trunks
Key Parameters: PCR & MCRKey Parameters: PCR & MCRFeedback Loop: Available bandwidthFeedback Loop: Available bandwidth
adjusts to network conditions.adjusts to network conditions.MCR < Available Bandwidth < PCRMCR < Available Bandwidth < PCR
ATM Classes of ServiceATM Classes of Service
Unspecified Bit Rate (UBR)Unspecified Bit Rate (UBR)Data traffic flying standbyData traffic flying standby EMailEMail FaxFax
Key Parameter: PCRKey Parameter: PCR
ATM BackboneATM Backbone
ATM ‘Cloud’ Trunks use StatMux & Cell Switching CBR trunk traffic may use TDM & Cell Switching
ATM SwitchATM Switch
TrunksLeased Line
ATM Call Admission ControlATM Call Admission Control
Procedure for setting up SVC’s & PVC’s Procedure for setting up SVC’s & PVC’s End user requests call set-upEnd user requests call set-up
Provides destination, CoS, parametersProvides destination, CoS, parameters Switches determine if resourses areSwitches determine if resourses are
availableavailableSufficient Buffer Space?Sufficient Buffer Space?Sufficient unreserved trunk bandwidth?Sufficient unreserved trunk bandwidth?
Call is rejected if insufficient resourcesCall is rejected if insufficient resources
ATMATM
Hookups:Hookups:WAN see Frame RelayWAN see Frame RelayMAN see OSU BackboneMAN see OSU BackboneLAN see Switched EthernetLAN see Switched Ethernet
Performance:Performance:Depends on the Class of ServiceDepends on the Class of Service
ATM PerformanceATM Performance
0% 100%Trunk Offered Load
Probability of dropped cells
*Provided we are following traffic contract
UBR
ABR*VBR-nrt* & VBR-rt*
CBR
ATM PerformanceATM Performance
0% 100%Trunk Offered Load
Delays of delivered cells
*Provided we are following traffic contract
UBRABR*VBR-nrt* & VBR-rt*
CBR
Switched Network Carrying CapacitiesSwitched Network Carrying Capacities
0% Data 100% Data100% TST 0% TST
Offered Load
Carrying Capacity
Circuit Switch TDM
Packet Switch StatMux
Cell Switch StatMux
ATM StatusATM Status is flunking at the desktopis flunking at the desktop
Mixed Traffic? NoMixed Traffic? No Speed Advantage? NoSpeed Advantage? No $$$ savings? No$$$ savings? No PC protocols can’t handle QoSPC protocols can’t handle QoS
is succeeding on Carrier Backbonesis succeeding on Carrier Backbones Mixed Traffic? YesMixed Traffic? Yes Speed Advantage? No (at the moment)Speed Advantage? No (at the moment) $$$ savings? Competitive$$$ savings? Competitive
U.S. ATM WAN RevenuesU.S. ATM WAN Revenues
$0.0
1B ‘9
4$0
.03B
‘95
$0.0
6B ‘9
6$.
16B ‘9
7$0
.38B
‘98
$0.0
0B ‘9
3
$0.7
2B ‘9
9
Source:Data Communications
About 3-4 yearsbehind Frame
Carrier BackboneCarrier Backbone ATM SwitchATM Switch
Trunks
Carrier FrameCarrier Frame Relay Switch Relay Switch
Leased Line
ISP Router
Private ATM ‘Edge’ Switch
Carrier Voice Switch
ATM Backbone Carrying Mixed Traffic.Trunks are more effectively utilized.ATM Backbone Carrying Mixed Traffic.Trunks are more effectively utilized.
Frame Relay BackboneFrame Relay Backbone
A close look at the FRTrunks may reveal that...
FR Switch
TrunksLeased Line
Frame Relay over ATMFrame Relay over ATM
Carrier BackboneCarrier Backbone ATM SwitchATM Switch
Trunks
Carrier FrameCarrier Frame Relay Switch Relay Switch
Leased Line
ATMPVC
ISP Router...they are actually ATMVirtual Circuits.
Frame Relay over ATM Frame Relay over ATM
7 Application7 Application 6 Presentation6 Presentation 5 Session TCP5 Session TCP 4 Transport TCP4 Transport TCP 3 Network3 Network IPIP 2 Data Link 2 Data Link Frame Relay/ATMFrame Relay/ATM 1 Physical1 Physical