CSCI 690 CSCI-690 C omputer Networks: Shrinking the globe one click at a time Lecture 1 Khurram Kazi

New York Institute of Technology

Engineering and Computer Sciences

CSCI 690

CSCI-690Computer Networks:

Shrinking the globe one click at a time

Lecture 1

Khurram Kazi



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Major sources of the slides for this lecture

Some of the Slides used in this lecture are from Tanenbaum’s and William Stallings’ websites

K. Kazi Optical Networking Standards: A Comprehensive Guide for Professionals

Larry L. Peterson & Bruce S. Davie, Computer Networks: A Systems Approach



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Course Outline

This course provides an introduction to the fundamentals and the applications of data communications networks. Network architectures, topology, protocols, network services and models will be discussed. Some of the protocols the course will cover are: Protocols based on Internet Protocol (IP) (Layer 3 and above) Routing fundamentals and protocols within IP Network (Layer 3 and

above) Ethernet (10/100 Mb/s, 1/10/100(??) Gb/s Ethernet) (LAN, Metro and

Wide Area Networks) Synchronous Optical Networks (SONET) (Wide Area Network) Optical Transport Hierarchy (OTH) (Wide Area Network) MultiProtocol Label Switching (MPLS) (Layer 2.5) Switching and routing architectures will be presented

(Hardware/Software implementation architectures) Time permitting we will cover some aspects of Cellular Networking and

Next Generation Network Architecture (NGN) (Time permitting) Services provided by various networks (Time permitting) Network Security (Time permitting) OPNET (a premier network simulator) maybe be used in simulating

various aspects of networking concepts.



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Grading Policy

Assignments & short quizzes 30% 1 Midterm Test 30% Final Project 40% Final Projects will be in any topic of interest within

the Data Networking field There will be an Oral presentation of the project along with

a written report Class participation can sway the grade (so highly

encouraged, don’t be shy to ASK questions) NYIT’s Academic Integrity policy will be

strictly enforced. Any student found to be cheating (in the assignments, quizzes, Midterm etc.) will get a straight “F”



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Do’s and Don’ts for the Final Project

DO NOT use any report / design from the net. I will know if you did!!

Properly referenced work that is not plagiarized is acceptable

Most of it should be your work!! Select the topic that interests you. Be creative in it!

Designing some aspect in software or hardware will be highly encouraged as opposed to doing an overview/report on some networking technology

By mid semester have a good idea of your project Team of 2 students working on the same project is

allowed. Each team member’s task within the project should be

explicitly defined.



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Intended Results at the Culmination of the Course You should have a good understanding of

networking technologies Ability to implement (in software) varied

networking protocols Should be able to architecturally design various

components of the diverse networks Design of a router/switching Network Element

Protocol Handling/protocol stacksLine CardsSwitch FabricsHave a good understanding of various

WAN/MAN/LAN Technologies Ability to figure out which aspect is

implemented in hardware and what is designed in the software



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Recommended Books

1) The Internet and Its Protocols; A Comparative Approach, Adrian Farrel, Morgan Kaufmann Publishers, 2004, ISBN 1-55860-913-X

2) Computer Networking: A Top-Down Approach, Kurose, Ross, 5th Edition, Addison-Wesley, 2010, ISBN 978-0-13-607967-5

3) Computer Networks: A Systems Approach, Larry L. Peterson & Bruce S. Davie, 4th Edition, Morgan Kaufman, 2007, ISBN 978-0-12-370548-8

4) Computer Networks, Andrew S. Tanenbaum, 4th Edition, Prentice Hall, 2003, ISBN 0-13-066102-3

5) Internetworking with TCP/IP Principles, Protocols, and Architectures, 4th Edition, Volume 1, Prentice Hall, 2000, ISBN 0-13-018380-6

6) Optical Networking Standards: A Comprehensive Guide for Professionals, edited by Khurram Kazi, Springer, 2006, ISBN 0-387-24062-4



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Useful websites

Tanenbaum’s website at Prentice Hall http://authors.phptr.com/tanenbaumcn4

William Stalling’s (Another good text book on data and computer networks) Website http://www.williamstallings.com/DCC/DCC8e.html

Excellent site for the latest trends in networking www.lightreading.com

Standards Organizations and Industry Forums Internet Engineering Task Force

http://www.ietf.com MetroEthernet Forum

http://metroethernetforum.org International Telecommunication Union (ITU): The leading United Nations

agency for information and communication technologies http://www.itu.int

IEEE (Institute of Electrical and Electronics Engineers) LAN/MAN Standards Committee http://www.ieee802.org

OPNET (Network simulator that we will be using) www.opnet.com



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Standards Organizations: ITU

Main sectors• Radiocommunications• Telecommunications Standardization• Development

Classes of Members• National governments• Sector members• Associate members• Regulatory agencies



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Standards Organizations: IETF

The Internet Engineering Task Force (IETF) is a large open international community of network designers, operators, vendors, and researchers concerned with the evolution of the Internet architecture and the smooth operation of the Internet. It is open to any interested individual. The IETF Mission Statement is documented in RFC3935.



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Standards Organizations: IEEE 802 Standards

The 802 working groups. The important ones are marked with *. The ones marked with are hibernating. The one marked with † gave up.



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Implication of the Designs we work on; keep few things in mind!

During the design process we always make trade-offs Trade-offs can be based on time to market, cost

implications, complexity, environmental considerations etc. Ethics: Keep in mind the implications of what you are

designing, how it impacts the society!! Privacy vs. Security is a big issue in networking

Network designs inherently deal with Implementing of standardized solutions based on regional or global

standards developed by industry forums or international standards organizations

Power consumption considerations: Making the Designs Green; Environmental friendly!! Especially true for Data Centers, cell sites and cellular networking infrastructure etc.

IEEE 802.3AZ working group has defined Energy Efficient Ethernet PHY specification

Cost/performance trade-offs



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Efforts within IEEE 802.3AZ work Group to Conserve Energy



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Methods to Save Energy Reduce Link Rate

Can (and does) save energySome NICs drop link rate when a laptop is

battery powered–Or, when a PC goes into sleep stateTurns-off PHY if no signal on link

Match the link rate to utilizationHigh utilization = high link rateLow utilization = low link rate

Currently implemented using auto-negotiationSet the Technology ability bits/message codes and

then reset the linkTakes about 1000 milliseconds (a loooooooong

time)



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Methods to Save Energy Need for fast transitions Need for fast transitions

Can extend the benefits of link data rate reduction By making the data rate transition faster

Need a faster way than auto-negotiation When I need high data rate, I need it now Can’t advertise the desire to change to a higher speed

Need a mechanism that is transparent to upper layers

Need a standard mechanism to rapidly transition: From low to high data rate From high to low data rate

Within the capabilities established by Auto Negotiation

IEEE Working Group 802.3AZ has developed the Energy Efficient Ethernet PHY specification



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Uses of Computer Networks

• Business Applications• Home Applications• Mobile Users• Social Issues• Vehicular networks• Industrial/manufacturing networks



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Business Applications of Networks



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Business Applications of Networks (2)

The client-server model involves requests and replies.



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Home Network Applications

Access to remote informationPerson-to-person

communicationInteractive entertainmentElectronic commerce



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Home Network Applications (2) In peer-to-peer system there are no

fixed clients and servers.



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Network Applications

Some forms of e-commerce.



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Types of Network

Metropolitan Area NetworksLocal Area NetworksWide Area NetworksCellular NetworksWireless Networks (could be

Broadband Networks or LANs)Home NetworksInter-networks



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Network classification based on distances

Classification of interconnected processors by scale.



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Fuzzy Networking Demarcation Points

Metro Edge

Metro Area Network

(Metro Core)

Premise(Enterprise Networks)

Metro Edge

Metro Area Network

(Metro Core)

Wide Area Network(Core/backbone/

Long Haul)

Bigger Pipes less intelligence in transportSmaller Pipes Higher intelligence in aggregation/

switching

Premise(Enterprise Networks)



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Communications Tasks

Transmission system utilization Addressing

Interfacing Routing

Signal generation Recovery

Synchronization Message formatting

Exchange management Security

Error detection and correction Network management

Flow control



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A Communications Model

or cable/DSL modem

or cable/DSL modem or cable network



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Data Communications Model



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Transmission Medium

Selection is a basic choice internal use entirely up to business long-distance links made by carrier

Rapid technology advances change/mix various transmission medium fiber optic Copper Cable (still alive and widely used) Wireless (microwaves, satellite, light waves, cellular

etc.) Transmission costs still high (but decreasing as

time progresses) Hence interest in efficiency improvements

(never ending so to speak!)



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Some of the Drivers for Innovative Networking Technologies

Growth of number & power of computers is driving need for interconnection

also seeing rapid integration of voice, data, image & video technologiesVoice over IP IPTVTraditional net connectivity for data

transmissionsGaming industry

Interactive gaming services enabling multiple players across diverse geographical locations



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Types of Networks: Wide Area Networks

Span a large geographical area Cross public rights of way Rely in part on common carrier circuits Technologies used include:

circuit switching packet switching (IP or MPLS based) Ethernet based transport Legacy Technologies

frame relay Asynchronous Transfer Mode (ATM)



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Types of Networks:Wide Area Network



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Relation between hosts on LANs and the subnet.




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A stream of packets from sender to receiver.



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Circuit Switching

Uses a dedicated communications path established for duration of conversation

Comprising a sequence of physical links with a dedicated logical channel

e.g. telephone network



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Packet Switching

Data sent out of sequence over diverse paths

Small chunks (packets) of data at a time

Packets passed from node to node between source and destination

Used for terminal to computer and computer to computer communications



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Types of Networks:Metro Area Network

MANMiddle ground between LAN and WANPrivate or public networkHigh speed Large area



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Headquarters to Printing site(15 miles)

HQ to Carrier Hotel(5 miles)

Printing Site to Carrier Hotel(15 miles)

2 Gigabit Ethernet Channels2 Fibre Channels1 multiplexed fiber (T1, T3, 10/100 Ethernet

1 Gigabit Ethernet Channels1 multiplexed fiber (T1, T3, 10/100 Ethernet

1 Gigabit Ethernet Channels1 multiplexed fiber (T1, T3, 10/100 Ethernet

Headquarters

Carrier Hotel

Printing site



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A metropolitan area network based on cable/Satellite service providers.



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Types of Networks:Local Area Networks

Smaller scopeBuilding or small campus

Usually owned by same organization as attached devices

Data rates much higherSwitched LANs, e.g. EthernetWireless LANs



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Types of Networks:Local Area Networks

Two broadcast networks (a) Bus (b) Ring



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Types of Networks:Wireless Networks

Categories of wireless networks:

System interconnectionWireless LANsWireless WANs



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(a) Bluetooth configuration (b) Wireless LAN



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(a) Individual mobile computers (b) A flying LAN (several airlines

offer internet connectivity during flights)



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Types of Networks:Home Networking

Computers (desktop PC, PDA, shared peripherals

Entertainment (TV, DVD, VCR, camera, stereo, MP3)

Telecomm (telephone, cell phone, intercom, fax)

Appliances (microwave, fridge, clock, furnace, air-conditioning etc.)

Telemetry (utility meter, burglar alarm, babycam).



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Home Networking:Digital Living Room

Digital Living Network Alliance (DLNA) http://www.dlna.org/en/industry/about



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The Internet Internet evolved from ARPANET

first operational packet networkapplied to tactical radio & satellite nets alsohad a need for interoperability led to standardized TCP/IP protocols



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Internet Elements

SONET/OTH (MPLS based routing)



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Internet Architecture



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Example Configuration

Documents

CSCI 690 CSCI-690 C omputer Networks: Shrinking the globe one click at a time Lecture 1 Khurram Kazi