DOC PREVIEW
UCCS CS 622 - Data Network Design

This preview shows page 1-2-3-4-26-27-28-53-54-55-56 out of 56 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 56 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

3-location Data Network DesignVoice Traffic vs. Data TrafficData Traffic StatisticsData Base TrafficCost of Services and ComponentsData Network Design Principle 2.2BurstinessCommon Data RateToken Ring vs. Packet SwitchingM/M/1 QueueM/M/1 Average Waiting TimeTotal Delay (50ms service time)Initial Data Network DesignCost of Initial DesignTraffic in Busy HourDesign Principles 2.3 & 2.4Apply M/M/1 FormulaSlide 18Calculating Internal Email TrafficTabular Represenation of Internal Email TrafficExternal EmailTabular Represenation of External Email TrafficBusy Hour WWW TrafficSlide 24DB Query FlowBusy Hour DB TrafficDB Traffic TableBusy Hour Traffic (64kbps links)Busy Hour TrafficDrop Algorithm for Network DesignRouting in SNAOPSF RoutingRouting Information ProtocolAssumptions for Drop AlgorithmDrop AlgorithmModified Drop Algorithm CodeApply Drop Algorithm on Initial DesignTraffic Flow After Removing Link to GateCSlide 39Traffic Flow After Removing Link To GateBRound 3 & Round 4Traffic Flow After Removing Link btw Bregen and CharmesRounds 4, 5, 6Drop Algorithm ResultWhere the Drop Algorithm Went Wrong?Final DesignHomework #5Solution to Hw#5Exercise 2.6Slide 50Traffic after Eliminating Charmes’ Internet LinkTry to Eliminate InterSite LinksFinal Low-Cost SolutionExercise 2.8Slide 55Final Solution01/15/19 C. Edward ChowCS622 Page 13-location Data Network Design•3 locations separated by 200 km among pairs.•Give the new populations below 296 users, design the data network.01/15/19 C. Edward ChowCS622 Page 2Voice Traffic vs. Data Traffic01/15/19 C. Edward ChowCS622 Page 3Data Traffic Statistics•20% of internal email, www, DB traffic occurs in the busy hour. •External email arrives evenly during the day.•Avg. internal email size 60kB. External email size 12kB.•Each url request generates 6 datagrams to server, 6 datagrams back to client for setup connections, a datagram avg. 128B.•Its http response is 2kB datagram.01/15/19 C. Edward ChowCS622 Page 4Data Base Traffic•Data distributed in 3 servers, one at each site.•Each employee makes 100 queries and 5 updates.•Query:–Query first goes to the local server, then go the remote server. Will there need to go to third server?–Query packet avg. 800B, response packet avg. 3500B.–Probability of data in a server is 1/3. Evenly spread.•Update: –Update packet avg. 6000B, response packet 500B.01/15/19 C. Edward ChowCS622 Page 5Cost of Services and ComponentsCost of PC’s, workstations, servers not considered.Routers can handle 2000 datagrams/sec >> the traffic Delay can be neglected.01/15/19 C. Edward ChowCS622 Page 6Data Network Design Principle 2.2•Blocking in not important; delay is the issue.•Highly utilized links are not desirable (large delay).Design Principle 2.2•In a voice network, highly utilized links can be cost-effective, since they exploit the available bandwidth to the fullest extent, and when the link is given to a connection it receives a high grade of service (circuit switch).•In a data network, highly utilized links are terrible since all call traffic using that link suffers inordinate delay.01/15/19 C. Edward ChowCS622 Page 7Burstiness•Burstiness= peak rate/avg rateTwo solutions to simultaneous arrive of data calls:•Coordination- e.g., token ring. Allow one to be servered. But is not good for WAN.Propagation delay (p.d.) for 1000 mile ring=1000/186000=5msTransmission delay for 1000 bit packet at 16Mbps=1000/16000000 << p.d.•Queueing or use store and forward (packet switching idea).01/15/19 C. Edward ChowCS622 Page 8Common Data RateThe service time for a packet of n bits on a link of speed S bps is n/S01/15/19 C. Edward ChowCS622 Page 9Token Ring vs. Packet SwitchingPropagation delay for 1000 mile ring=1000/186,000=5.376 msTransmission delay for 1000 bit packet at 16Mbps=1000/16,000,000 =0.0625msFor WAN, token ring protocol is not suitable.A packet switching network where each link segement operates independently is a more efficient design. Packet switching network can be modeled as a set of queues.01/15/19 C. Edward ChowCS622 Page 10M/M/1 Queue•Link can be modeled as a M/M/1 queue.01/15/19 C. Edward ChowCS622 Page 11M/M/1 Average Waiting Time01/15/19 C. Edward ChowCS622 Page 12Total Delay (50ms service time)01/15/19 C. Edward ChowCS622 Page 13Initial Data Network Design01/15/19 C. Edward ChowCS622 Page 14Cost of Initial Design•Transit router amortized cost: $3700*0.03=$111/month•64kbps (or D64) internode link $700/month•64kbps internet link $1400/month.01/15/19 C. Edward ChowCS622 Page 15Traffic in Busy Hour•20%=0.2 traffic in busy hour.01/15/19 C. Edward ChowCS622 Page 16Design Principles 2.3 & 2.42.3: Seek to make a network where all the links have a 50% utilization2.4: Seek to make a network where all the links have about 50% utilization and as few links as possible are underutilized.Example:Question1: How we calculate the delay?Question2: For high speed link, can we have high utilization?01/15/19 C. Edward ChowCS622 Page 17Apply M/M/1 Formula•Assume 1000 bytes packet (8000 bits).•Case1: T1 link=1.536Mbps, 50% utilization•Case2: OC-3 link=135Mbps, 80% utilization•Which one has lower delay?01/15/19 C. Edward ChowCS622 Page 18Apply M/M/1 FormulaCase1: T1 link=1,536,000 bps, =0.5 (50%utilization)•1/= service time=packetsize/transmission speed=8000/1536000•T=(1/)/(1-)=(1/(1-))*(1/)=(1/(1-0.5))*8000/1.536M=10.4 ms.Case2: OC-3 link=135Mbps, =0.8 (80% utilization)•T=(1/(1-0.8))*(8000/135M)=5*(8000/135M)=2.96ms•We may be willing tolerate a higher utilization on these links. But their delay is quite “unstable”.01/15/19 C. Edward ChowCS622 Page 19Calculating Internal Email Traffic•Internal Email: relate to the populations of source and destination sites. The ration of populations among Anagon, Bregen, and Charmes=(1, 4/3, ¾)•Let x be the volume of internal email from Analog to itself. •Then the traffic from Anagon to Bregen is 4/3 x.•The traffic from Anagon to Charmes is ¾ x.•busy hour internal email: 10*0.2*60000*8*296/3600(s)=78933 bps.•Counting all directional internal email traffic: 9.507x=78933bps  x=8303bps01/15/19 C. Edward ChowCS622 Page 20Tabular Represenation of Internal Email Traffic01/15/19 C. Edward ChowCS622 Page 21External Email•In the initial design, each site has its own Internet connection. Therefore the external emails does not go through inter-site internal


View Full Document

UCCS CS 622 - Data Network Design

Documents in this Course
Fast TCP

Fast TCP

34 pages

Load more
Download Data Network Design
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Data Network Design and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Data Network Design 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?