Internet Technology & Quality of Service

Internet Technology & Quality of Service Notes on OSI Model vs TCP/IP Eduard Babulak Ph.D., P.Eng., Eur. Ing., C.Eng., SMIEEE International Scholar on Sabbatical Staffordshire University, United Kingdom Visiting Professor of Computer Science University of Quebec in Rimouski, Canada

Massachusetts Institut of Technology Universidad Carlos III de Madrid

November 7th, 2005, Cambridge, MA

Agenda Past, Current Internet – – – –

• •

Internet Origins & Development Corporate Network Standards & Networking Standards Organizations Protocols

OSI Model vs. TCP-IP Future Internet & Ubiquitous Communications Technologies – Keywords • • • • •

• •

What’s Next for the Internet & Society Quality of Service for the Internet – – – –

•

Next Generation of Applications & Convergence Internet & Wireless World Wireless Market Revolution Cambridge 4G Network Ubiquitous Computing

Definition – Principles - Specifications Predictable Internet QoS Adaptable Service Infrastructures Intelligent Internet Infrastructures

Summary & Questions – Case Study: Staffordshire University Campus Network • Methodology to Assess the Users’ Perception of QoS Provision

8/20/2015

MIT Cambridge, MA Universidad Carlos III de Madrid

2

INTERNET ORIGINS and DEVELOPMENT • • • • • • •

1964 Paul Baran The Rand Corporation, 1964 A distributed network for sending digitally encoded messages in packets 1969 Advanced Research Project Agency –ARPANET started UCLA (Leonard Kleinrock) to Stanford 1971 First e-mail network 1974 Telenet- First commercial version of Arpanet Bolt-Beranek and Newman (BBN) Multiple networks ARPANET, DECNET, EDUNET, USENET, NSFNET 1982 Transmission Control Protocol /Internet Protocol TCP/IP Vinton Cerf Robert Kahn 1985 All Canadian Universities connected to NetNorth

8/20/2015 Credit to Professor C C Gotlieb


3

INTERNET ORIGINS and DEVELOPMENT • •

1988 Canada joins NSFNET backbone 1989/1990 World Wide Web (WWW) created by Tim BernersLee Hypertext Communication Protocol http Hypertext Markup Language html Arpanet ceases There are 100,000 internet hosts worldwide

A Global Network of Networks Hosts

1999

43 million

2001 160 million

Almost doubles every year Web pages 1999 500 million

2002

6 billion V. Cerf Comm.ACM Sept ’01

Content Short text, files, pictures, online chats, real time audio, video Ever more bandwidth 8/20/2015 Credit to Professor C C Gotlieb


4

Past Internet ARPANET: 1969 To provide data exchange between main frames in research labs

TCP: 1973 Split into TCP and IP, TCP/IP: 1978 Commercial system: mid-1990

Current Internet LAN Local Area Networks MAN Metropolitan Area Net. WAN Wide Area Net.

INTERNET or

Global Inter-network 8/20/2015 Credit to Fourozan


5

Corporate Network

8/20/2015 Credit to Fourozan


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Standards • Standards are documented agreements containing technical specifications or other precise criteria that stipulate how a particular product or service should be designed or performed Why is it essential? Public agreement for the interoperability of data and technologies among devices manufactured by different companies

De facto: by convention (fact) De jure: by regulation (law) Advantages of having standards? Easy deployment of technologies Less cost of devices 8/20/2015 Credit to White


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Networking Standards Organizations

• Committees – ISO (International Organization for Standards) – ITU-T (International Telecommunication Union – Telecommunication Standards) – ANSI (American National Standard Institute) – IEEE (Institute of Electrical and Electronics Engineers) – EIA (Electronic Industries Association)

• Forums – ATM – WWW

• Internet standards – ISOC (Internet Society) • IETF (Internet Engineering Task Force): http://www.ietf.org • RFC (Request For Comment) 8/20/2015


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Protocols – Rules a network uses to transfer data – Protocols that can span more than one LAN segment are

routable

• Multi-protocol Network – Network using more than one protocol – What, how and when – Key elements

• Syntax: the structure or format of the data – Header + body + trailer

• Semantics: the meaning of each section of bits • Timing: when and how fast

8/20/2015 Credit to White


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OSI Model

TCP/IP

ISO INTERNATIONAL STANDARD ORGANIZATION

ITU International Telecommunication Union

100% at physical and data link layers

IETF (Internet Engineering Task Force Transmission Control Protocol/Internet Protocol (TCP/IP)

70% to 80% at the Internet and transport layers. Also strong at the application layer

Open System Interconnection build 1980 by ISO

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TCP/IP vs OSI Architecture Layer

Specific Purpose

General Purpose

Application (5)

Application-application interworking

Application-application interworking

Transport (4)

Host-host communication

Transmission across an internet

Internet (3)

Packet delivery across an internet

Data Link (2)

Frame delivery across a Transmission across a network single network (LAN or WAN) Device-device connection

Physical (1)

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TCP/IP and the OSI Model



12



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Keywords for the Future Communications Technologies

• Convergence – Applications Attributes – Technology Integration

• Future of Wireless – The Converged World – – – –

Phone Melting Pot Melting Point of Applications Wireless Market Evolution The Road to 4G… • • • • •

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OFDM Broadcast Multiple Pipes Cognitive Radio Cambridge 4G Network MIT Cambridge, MA Universidad Carlos III de Madrid

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Applications Attributes: •

Collaboration across distributed heterogeneous platforms with:

Q o S

– Adaptability • Session mobility – switching between different terminal devices & display resolutions » black & white » color 640x480, 800x600, 1280x1024 or 1600x1200 pixels

P r o v i s i o n

– switching between different service providers & locations of servers » reduced latency

– Scalability • An application is scalable if its performance metrics can improve, as necessary and essentially without limit, by adding equipment (more hosts, more network connections, etc) and without the need for replacement of existing equipment. • Further, equipment cost should increase at most linearly with performance metrics, so that the cost per unit measure of performance is constant or declines.

– Reliability • System ability to deliver continuous quality service 8/20/2015 Credit: Messerschmitt 2000


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Technology Integration •

Server

Evaluate QoS Provision

Real Audio

– Highly Interactive Applications

•

Support Interoperability

Workstation

– Heterogeneous Environments – Open Networking

•

Camera

Support Integration

Network

– Wide range of End devices • CISCO ATM Switch, IP Router with standard interfaces

Home Video

Video Title

– Internet Openness • Attach any network using IP

Disc

• Attach any device • Anywhere – anytime • Ad-hoc networks • Mobility 8/20/2015


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Convergence: Voice, Data and Video

Voice Office

Travel Hotspots

Home

Device Independence • Mobile IP • Content Translation • Quality of Service • VPN • Content Networks

Vacation Hotspots

Intranet

Web Calendar Email

Communication E-Learning

8/20/2015


17 Credit to Dr Ravi Kalakota

The Future of Wireless – The Converged Device ANY NETWORK

ANY DEVICE

Mobile

Enterprise

SEAMLESS CONNECTIVITY Any device, Any where, Any time, Any network

Home ANY WHERE

ANY TIME

Bringing together… 8/20/2015 Credit: Dr. Rick Wietfeldt Texas Instruments

Communications and Entertainment


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The Future of Wireless – The Converged Device SEAMLESS CONNECTIVITY

ANY DEVICE

ANY NETWORK

Cellular UMTS

HSDPA

HSUPA

EDGE GPRS

GSM

802.16d

WMAN 802.11g

802.16e

Bluetooth®

Galileo

ISDB-T

802.11a

WPAN 802.11n

Broadcast DTV DVB-H

4G

WLAN

Navigation A-GPS

3.9G

802.11b

UWB DMB

FM Broadcast Radio DRM HD DAB

RFID

ANY WHERE

ANY TIME

http://3g.cellular.phonecall.net/links.html#htop

8/20/2015 Credit: Dr. Rick Wietfeldt Texas Instruments


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Melting Pot of Technologies Communications + Entertainment OMAP: TI Multimedia Microprocessor VOX: Voice Operating Switch

HLOS: High Level Operating Systems HSDPA: High Speed Download Packet Access UMTS: Universal Mobile Telecomm System EDGE: Enhanced Data Rates for GSM

GPRS: General Radio Packet Service GSM: Global System for Mobile Comm.

http://grouper.ieee.org/groups/802/15 /

http://3g.cellular.phonecall.net/ http://www.umtsworld.com/technology/edge.htm http://www.umtsworld.com/technology/hsdpa.htm http://focus.ti.com/docs/pr/pressrelease.jhtml?prelId=sc05040

WPAN: Wireless Private Area Networks

8/20/2015 MIT Cambridge, MA http://focus.ti.com/general/docs/wtbu/wtbugencontent.tsp?templateId=6123&navigationId=11988&path=templatedata/cm/general/data/wtbovrvw/omap Credit: Dr. Rick Wietfeldt Texas Instruments

Universidad Carlos III de Madrid

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Melting Pot of Applications Communications + Entertainment Audio  Dolby audio and 3D audio effects

Gaming

 3D interactive  Up to 2 million polygons per second

Imaging  Up to 6

Display  CIF, VGA  Up to D1

megapixel

Video  VGA video  Up to DVD

TV

 Broadcast DTV

quality

reception  TV output

http://www.spectraintl.com/xcic/cif.html



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Wireless Market Evolution - Cellular http://standards.ieee.org/wireless/

Today

3.9G/ OFDM

http://www.wireless.com/ 3G 2.5G/ 2.75G 2G

1G

Digital Cellular 

Analog Cellular



Voice  AMPS, TACS









Voice Pager 10kbps data GSM, TDMA CDMAOne


Wide-Band Digital Cellular

Digital Cellular    



 

4G

Voice Email Photos Web ~100kbps data GPRS/EDGE CDMA 2000 1X

   





Video M-pixel cam. 3D 300kbps  14Mbps UMTS, WCDMA, HSDPA CDMA 1X EVDO


Wide-Band Digital Cellular  





  

Video High-end gaming 100 Mbps, 10msec Flexible bandwidth Super 3G HSOPA MC-CDMA

Wide-Band Network 







Ubiquitous data Flexible Spectrum use Enhanced apps. 100Mbps – 1Gbps

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Wireless Market Evolution continued…

The wireless world is accelerating. 3G is quickly moving on to 3.5G, 3.9G and 4G and is changing the way the world communicates. The evolution of wireless technologies including cdma2000, GPRS, EGPRS, W-CDMA, HSDPA and 1xEV, allow development of new wireless devices that combine voice, internet, and multimedia services. Source: http://www.home.agilent.com/ http://www.home.agilent.com/USeng/nav/pc.html?CT=AGILENT_COLLECTION&ID=0000100110001:csg:ind&cmpid=90188

5 G Wireless Communications – Human Centric Computing http://www.5gwirelesssolutions.com/ http://www.mobilein.com/mobile_in_a_minute.htm 8/20/2015


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Wireless Market Evolution continued… Cognitive Radio: Federal Communications Commission « FCC » These technologies can enable a radio device and its antenna to adapt its spectrum use in response to its operating environment. The technology provides a variety of options for a radio device/antenna to identify available spectrum that is unusable under current conditions. Source:

http://www.fcc.gov/oet/cognitiveradio/

Orthogonal frequency division multiplexing (OFDM) technology in wireless applications Source: http://www.ofdm-forum.com/index.asp?ID=92

http://www.ofdmnews.com/ 8/20/2015


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Cambridge :4G Mobile Systems

UK IPv6 Resource Centre Lancaster University Computing Department http://www.cs-ipv6.lancs.ac.uk/ipv6/ 6Bone/Whois/

http://www.ipv6.org/

Objectives: To realise an all-IP network and to develop innovative solutions to tackle the limitations of Mobile IP in supporting mobile devices in a heterogeneous network environment.

8/20/2015 Source: http://www-lce.eng.cam.ac.uk/research/?view=2&id=27


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What’s Next for the Internet? • • • • •

• • • •

Connectedness Now-- Anybody is connected to everybody RFIDs (Radio Frequency Identifiers) WiFi New protocols for interconnection Convergence---E-mail, voice, pictures—all from the same device To come-- Anything is connected to everything! Understanding Smarter search engines (Google, Yahoo, Microsoft) The Semantic Web (Tim Berners-Lee) Perhaps you will be able to ask your refrigerator if it has a good supper on hand and if not, tell it to instruct your car to pick up something at the supermarket drive-in.



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What’s Next for the Internet? Multilingual Currently 52 % of websites are in English --- this percentage is dropping rapidly Already China has more users online than the USA

Continuing decrease in cost Moore’s Law For constant cost, processor speed, memory size double every 18 months

Valid for three decades, and expected to stay so for several more cycles  Ever smaller, more versatile, cheaper devices Many devices now affordable even for those in poor countries



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What’s Next for Society New institutes for studying effects of the Internet on Society Oxford University, United Kingdom

University of California at Berkeley

Another trend

More surveillance---less privacy!

Hard lesson Once a technology becomes very widely deployed, there are unanticipated side effects, not always beneficial Internal combustion engine, motor cars huge dependence on oil highway networks fill the city and countryside Television –not mainly educational as was at first hoped and believed medium captured by commercial and entertainment interestObesity! Nuclear power Dangerous waste products, lasting for centuries



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Quality of Service (QoS): Definition • QoS is the ability of network element (e.g. an application, host or router) to have some level of assurance that its traffic and service requirements can be satisfied. • To enable QoS requires the cooperation of all network layers from to-to-bottom, as well as every network element from end-to-end. • Any QoS assurances are only good as the weakest link in the chain between sender and receiver. Cristina Aurrecoechea, Andrew T. Campbell, and Linda Hauw, “Survey of QoS Architecture”, Multimedia Systems Journal, Special Issue on QoS-A, 1997

Disk & Thread scheduling

Protocol stack Media source

8/20/2015

packet scheduling and flow control

Internetwork

QoS monitoring and maintenance

to internetwork Protocol stack

End-to-end admission control & resource reservation


Credit to: Postech Networks and Distributed Systems Laboratory

Playout device

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Cristina Aurrecoechea, Andrew T. Campbell, and Linda Hauw, “Survey of QoS Architecture”, Multimedia Systems Journal, Special Issue on QoS-A, 1997

QoS Principles •

Integration principle – QoS must be configurable, predictable, maintainable – Must be supported by all networks & system components • Source media device • Source & receiver protocol stack • Network

•

Separation principle – Individual functionality must be separated in architectural QoS framework • Media transfer • Control • Management

•

Transparency principle – Hiding complexity of QoS architecture from application – Must support abstracted QoS based API

•

Performance Principle – Related to implementation • Communication protocols structures & processes

•

Multiple timescale principle – QoS functional activity have different time scales & must be coordinated Control 8/20/2015

Management MIT Cambridge, MA Universidad Carlos III de Madrid


Time scale 30

Cristina Aurrecoechea, Andrew T. Campbell, and Linda Hauw, “Survey of QoS Architecture”, Multimedia Systems Journal, Special Issue on QoS-A, 1997

QoS Specifications •

Flow synchronization specification – Degree of synchronization between multiple related flows

•

Flow performance specification – User’s flow performance requirements • Throughout, delay, jitter, loss

– Quantitative QoS specifications

•

Level of service – Degree of end-to-end resource commitment • Deterministic, predictive, best-effort

– Quantitative QoS specifications

•

QoS Management Policy – Degree of QoS adaptation • In the event of violation of the contracted QoS

– Include application level selection for QoS indication

•

Cost of service – Specification of the price for the service level

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Quality of Service: QoS IT Survey

User Specified QoS

Application Specified QoS Media Quality - Media Relations

20 FRAME/sec - 640X320 PIXELS - 256 COLORS

Transmission and Operating Communications HP System Specified QoS OpenView Quantitative Criteria (throughput, delay, error-rate) Qualitative (synchronization, error recovery, scheduling, etc.)

Network QoS Parameters Requirements on Network Resources

Bandwidth

Timing and throughput demands

Net. Load (nodal service units) Performance (jitter, cell-loss) Traffic Contract Parameters

8/20/2015

Multimedia Devices QoS Frame-rate


delivery

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User Perspective Image size, Color depth Voice quality, Steady picture, etc.

Transmission cost

The QoS Venn diagram

Application Perspective

Response Time

Delay Jitter

Bandwidth Throughput, Burstiness, Compression, Transport technique

Delay, Jitter, Skew, Error rate

Throughput, Delay. Delay variance, Error rate

Transmission Perspective 8/20/2015


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Quality of Service for the Internet In the past, improving the quality of service required router nodes to maintain detailed information about the datagrams (i.e. the messages) (they have to be stateful, rather than stateless, as they now are) This increases complexity of nodes and the network loses its scalable property This changes with proposal of Ion Stoica Stateless Core: A Scalable Approach for Quality of Service in the Internet Springer, 2004 “In SCORE only edge nodes (those at the borders of the network) maintain per flow state and perform flow management; core nodes ( those in routers in the interior of the network) do not perform any flow state. The network as a whole still retains its highly desirable scalable property 8/20/2015 Credit to Professor C C Gotlieb


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Predictable Internet QoS 1) Investigate mechanisms to deliver predictable rather than guaranteed QoS on the Internet. 2) Lack of QoS provision due to the Internet Inherent Complexity and lack of Scalability features. 3) Proposed solutions: Smart Load Management and Load Distribution in an end-to-end manner. 4) The high level idea is that if the load can be well managed, then no additional QoS techniques are needed. 5) As a result, a predictable Internet will spur growth in media applications as well as web services.

8/20/2015

MIT Cambridge, MA Universidad Carlos III de Madrid http://www.hpl.hp.com/research/issl/projects/network/index.html

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Adaptive Service Infrastructures Internet services experience wide fluctuation in client demand while their server and network resources frequently suffer from congestion and outages. Current research broadly addresses challenges in designing an infrastructure that enables distributed services to meet performance and availability objectives under dynamic demand and resource conditions. Challenge to explore the characteristics of demand variations in real services and their implications for adaptive infrastructure policies. Characteristics of the demand such as the distribution of clients over the network and the variation of demand across clients and over time are used to guide the design of service placement policies as well as history-based and predictive server allocation policies that can meet performance objectives. 8/20/2015 http://research.microsoft.com/aboutmsr/labs/default.aspx


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Adaptive Service Infrastructures continued…

Service performance can also suffer due to congested infrastructure resources, such as the network, which are shared with other services. Examining host and network switch mechanisms and policies to control congestion in the context of system area networks that will be deployed in data centers.

Extending investigation to consider other network resource control issues (e.g., for WAN environments) and address service availability issues. 8/20/2015 http://research.microsoft.com/aboutmsr/labs/default.aspx


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Intelligent Internet Infrastructures: Key Issues 1) Research efforts to design and management of dynamically scalable network systems and services, with special emphasis on performance. 2) What kind of intelligence, and where it should be added to the internet infrastructure to efficiently build the network overlays for diverse classes of applications with specified SLAs. 3) Content-aware request distribution that would enable intelligent routing for web services and allows to support additional QoS requirements.

4) Implementing and deploying, modular mechanisms for content-aware request routing. 5) System design and content/service placement should be client- and workloadaware. 6) Need to implement a workload analysis and monitoring tools which help to make the right decisions about the content/service placement at the network edge or across different data centers. 8/20/2015 http://research.microsoft.com/aboutmsr/labs/default.aspx


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Summary •

Past, Current Internet – – – –

• •

Internet Origins & Development Corporate Network Standards & Networking Standards Organizations Protocols

OSI Model vs. TCP-IP Future Internet & Ubiquitous Communications Technologies – Keywords • • • • •

• •

What’s Next for the Internet & Society Quality of Service for the Internet – – – –

•

Next Generation of Applications & Convergence Internet & Wireless World Wireless Market Revolution Cambridge 4G Network Ubiquitous Computing

Definition – Principles - Specifications Predictable Internet QoS Adaptable Service Infrastructures Intelligent Internet Infrastructures

Summary & Questions – Case Study: Staffordshire University Campus Network • Methodology to Assess the Users’ Perception of QoS Provision

8/20/2015


39

THANK YOU ANY QUESTIONS?

Case Studies: Staffordshire University Campus Network •

Staffordshire University Campuses over large geographic area – – – –

•

Over 18000 university plus adjunct colleges’ users – – –

•

Arts Computing Engineering, Business, etc.

Initial Design (5 years ago) – –

•

Students Academics Technical & Administrative Staff

Schools – – –

•

Stoke-on-Trent Stafford Lichfield Colleges

Simple Hub extended start topology based network No QoS technology

Current challenges – – –

Increased number of users More dynamics in traffic and application Students abuse of IT network •

MPEG3 Music files download (Galaxy) and interactive games etc

– Migration to CISCO Technology • Need for QoS provision assessment

– Future Recommendations to improve the QoS provision 8/20/2015


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Objectives

• Assess the University Network Quality of Service Provision in the Light of User’s Perception • Network Traffic Measurements • IT Survey • Suggest Performance Quality Improvements • Designing High Performance Systems and Scalable Architecture • Congestion Control Techniques • QoS Technologies • Migration to CISCO Technology • Local Cisco Academy 8/20/2015


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Case Study:

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Staffordshire Network Architecture


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Bits per second

Traffic Analysis for Mellor External Fast Ethernet Interface

Daily Graph (5 Minute Average) Max In: Max Out:

10.2 Mb/s (6.5%) 8238.1 kb/s (5.3%)

Average In: Average Out:

5583.5 kb/s (3.6%) 3484.2 kb/s (2.2%)

Current In: Current Out:

5462.0 kb/s (3.5%) 7729.3 kb/s (4.9%)

Hours during the day 8/20/2015


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Percentage

Utilization/Total Error 8/20/2015


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50

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IT Survey study area of customer perception of QoS

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IT Survey Customer’s QoS Requirements

Service Provider’s Offered QoS

Customer’s Perceived QoS

Service Provider’s Achieved QoS

The four fundamental QoS viewpoints. 8/20/2015


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Quality cycle 8/20/2015


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Discussion: IT Survey Results Campus Base Usage Frequencies

Respondent Type Frequency Percent Academic Staff

58

12.5

Clerical/Admin Staff

29

6.3

Management Staff

21

4.5

328

70.8

27

5.8

463

100.0

Student

Technical Staff Total

8/20/2015

Frequency Percent Lichfield

31

6.7

Other

12

2.6

Stafford

277

59.8

Stoke-onTrent

143

30.9

Total

463

100.0


56

Diagram representing the common usage of IT network

450 400 350 300 250 200 150 100 50 0

Usage Main usage

Univ campus 8/20/2015

Student Res

Home


57

Remote Connections 160 140 120 100 80 60 40 20 0 128K Modem

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56K Modem

ADSL

DSL


ISDN

58

Type of Operating System

Number

Window s NT

Window s 2000

Window s 95

Linux 0

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20

40

60

80


100

120

140

59

Daily Usage Pattern 350 300 250 200 150 100 50 0 12-3am 3-6am

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6-9am

912-3pm 3-6pm 12noon


6-9pm 9pm-12

60

User’s Session Duration Frequency More than two hours

Percent 199

44.1

Up to 10 minutes

12

2.7

Up to 30 minutes

38

8.4

Up to one hour

101

22.4

Up to two hours

101

22.4

Total

451

100.0

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Respondent Application Usage admin app

email First use Usage web

ftp

0

20

40

60

80

Percentage

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User’s Perception of the Application Performance Campus

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Student Residence

Home

Last use

5.1

4.4

4.4

ftp

4.0

2.8

3.3

Web

4.8

5.4

4.3

Email

5.5

5.4

4.6

Admin

5.0


4.1

63

User’s Attitude towards the Service received from the IT support

100% 90% 80%

Very poor

70%

Poor

60%

Reasonable

50%

Good

40% 30%

Very good

20%

Excellent

10% 0% Offcampus

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Student Res

Oncampus


64

Score Off-campus

3.7

Student residence

4.2

On-campus

5.5

The results of the survey show that the majority of average scores on scale Excellent=10, Very Good=8, Good=6, Reasonable=4, Poor=2, Very poor=0, lie between 4 and 6, indicating that respondents typically see response time lying between reasonable and good, on average. The only exceptions appear to be the use of ftp transactions, which are often seen as less than reasonable, particularly at a student residence or at home. 8/20/2015


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Correlation studies • From the network Measurement we establish that the half-duplex network utilization was 70%; • The users perception is within the limits of reasonable and good; • There is a correlation between the user’s satisfaction and the overall network utilization – With the increased level of utilization the user’s satisfaction is decreasing. 8/20/2015


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IT Network Current Developments • New 34 Mbps Automatic-Fail-Over resilient link was added in parallel to the ATM 622 Mbps link between Stafford and Stoke campuses to deal with heavy traffic. • There is a proposed 34 Mbps circuit between Stoke and Lichfield site as well for the year 2003. • The E-mail server sits on very powerful Mellor 5509 switch in Stoke – Switch Octagon 5509 has CISCO Interconnection Operating System (IOS) version 12 installed with fast Ethernet port and Gigabit uplink services.

• The Web-server configuration on the Octagon 5509 switch and the web-cache is in Stoke • Use of the “H drive” to store the students’ scholarly files. 8/20/2015


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The IT Measurements Policies: • Reactive (i.e. ad-hoc proactive activities): Old policies – This is due to the lack of personnel training for using exploiting the technology to its maximum.

• Active: New Policies – The Packeteer implementation purely on RESNET only starting from September 2002, which is very active measurement of the type of traffic at student residencies • Due to high volume of complaints about slow ftp service due to the fact that more than 50 % of traffic was generated by the Audiogalaxy music files transfers. • The packeteer solution will help to identify and to shape the traffic accordingly in order to give higher priorities to the work related type of traffic (i.e., ftp, file sharing) instead of the entertainment type of traffic (music, games, etc.)

• New DHCP implementation requiring all the users to register their MAC addresses from the DHCP in order to be allowed to get the dynamic IP address required connect to the IT network. 8/20/2015


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CASE STUDY’S Conclusions

• IT Survey – User’s Perception of the QoS Provision – SPSS Statistical Analysis

• Staffordshire University Network Architecture – Topology – IP Addressing Scheme: B and C Class

• Network Measurements Policies – HP OpenView – MRTG Router

• Our Recommendation to the IT Services – Implementing new QoS Technologies & Measurements Policies 8/20/2015


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Conclusions II: Our Recommendations – The use of QoS Technology resources including ATM, RSVP network architectures with capacity assignments based on application and transport level QoS parameters. – Apply more effective network monitoring policies • Measurements policies • Students Access Practices

– Implement more dynamic QoS provision technology • Session Mobility – Client – Server Initiated Session Switch

– Maintaining users’ satisfaction • As a result of our studies the IT Services are implementing new technologies following the result of our research • Cost effectiveness

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The QoS performance dimensions required by some common applications Performance Dimensions Application

Sensitivity to

Bandwidth Delay

Jitter

Loss

VoIP

Low

High

High

Med

Video Conferencing

High

High

High

Med

Streaming Video on Demand

High

Med

Med

Med

Streaming Audio

Low

Med

Med

Med

EBusiness (Web browsing)

Med

Med

Low

High

E-mail

Low

Low

Low

High

File Transfer

Med

Low

Low

High

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Application Traffic Categories

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Traffic Category

Example Application

Network Control

Critical Alarms, Routing, Billing, OAM

Interactive

VoIP, Interactive Gaming, Video Conferencing

Responsive

Streaming Audio/Video, Web browsing, eCommerce

Timely

E-mail, File Transfer MIT Cambridge, MA Universidad Carlos III de Madrid

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Discussion: Different QoS Technologies QoS Monitoring and Management

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ApplicationSignaled QoS

RSVP

IP QoS

IP Differentiated Services (DiffServ)

NetworkSignaled QoS

ATM, PNNI, MPLS RSVP-TE or MPLS CR-LDP

Traffic Engineered Path

ATM PVCs, MPLS Lable Switched Path (LSPs)

Link Layer QoS

Ethernet 801p, VLAN, ATM, MPLS, PPP, UMTS, DOCSIS, Frame Relay

Physical QoS

Wavelengths, Virtual Circuits (VCs), Ports, Frequencies

Layer


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Determinants of Performance Quality Factor

Description: Completion time versus throughput

Software architecture

The architecture of the application determine the partitioning of the application onto multiple host, which determines processing resources. It also addresses the relative location of data and processing. These both impact the communications overhead.

Technology

Electronics, magnetic and optical storage, and fiber optics are rapidly advancing. Application performance benefits directly from these technology advances.

Equipment

Computing systems and network exploits technology to provide processing, storage, and communications services to applications. Their performance is determined by both technology and their internal architecture and design.

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Congestion Control Implementation Techniques Approach

Description

Source Initiated

Sources detect network congestion, or are informed by the network (directly or through pricing), and limit the offered traffic. This has the advantage that sources can offer the most compelling traffic or shift less compelling traffic to another time.

Network Policing

The network enforces limits on the traffic it will accept from each source. The network may engage in flow control with each source, or it may silently drop excess traffic.

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Designing High Performance Systems and Scalable Architecture • • • • •

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Break the application down into small, atomic tasks, where each task will be assigned to one host (to avoid communication overhead. Characterize the resource requirements of each task. For example, how much processor execution time and memory and storage space does it consume? Analyse the communication pattern among tasks and in particular the communication burden on the network created created by assigning tasks to different hosts. Understand the scheduling constrains on the task. What task depends depends on the prior completion of others (i.e., parallelism, scheduling?) In light of these constraints, tentatively assign tasks to different hosts in a way that attempts to achieve the maximum parallelism and minimizes communication requirements. Tasks prioritisation for what task should be completed at what host most urgently to reduce the communications overhead. Analyse the proposed host assignment in terms of hot spots to points of congestion in either processing or communication, as well as, underutilised resources. What bottlenecks will ultimately limit overall application performance (i.e., response time to users)? 8/20/2015


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Future Internet & networking infrastructure http://www.hpl.hp.com/research/issl/projects/network/index.html Subsequent work with HP Managed Services and experience with deployment of multicast services has led to further research. The results produced strategic partnerships with Cisco Systems and new OpenView multicast management products in 2004. This work also led to experiments with stream quality assessment. Related interests include End-to-End Quality of Service (E2EQoS) and interdomain media and multicast management.

Media delivery - The Media Delivery team is developing technology and services for Internet broadcasting and media distribution networks. Streaming audio and video content is currently enriching the networking experience for more than 100 million desktop PC users. As both access bandwidth and wireless network technology deployment grow, higher quality multimedia information and entertainment will reach a growing audience through emerging network-connected appliances. http://research.microsoft.com/aboutmsr/labs/default.aspx 8/20/2015


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