SKR 3201: Internetworking (Antara Rangkaian)

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SKR 3201 Internetworking (Antara Rangkaian)

• Fahrul Hakim

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Introduction
Lecture name Fahrul Hakim Room Number A
1.29 Tel Number 017-6886542 Email
httpskr3201.blogspot.com Email fahrulhakim_at_gma
il.com Credit 3(3 0) Contact hours 3 x 1
jam kuliah seminggu Semester 2
(2008/09) Prerequisite SKR 3200
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Course Objective

• At the end of this course, student should be able
  
• To understand the main Internet protocol, its
  characteristics and functions.

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Synopsis
This course covers addressing, binding, routing,
Internet and application protocols, principles
and architecture of the global Internet. Focus
is given to the Transportation Control Protocol /
Internet Protocol (TCP/IP) Suite. (Kursus ini
merangkumi pengalamatan, pengikatan, penghalaan,
protokol applikasi dan Internet,prinsip dan
senibina Internet sejagat. Tumpuan diberikan
kepada Sut transportation control protocol /
Internet protocol (TCP/IP))
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Teaching Planning
SKR3201 (Sem.1 (08/09) Teaching Plan
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Chapter 1 Introduction and Overview

• fahrulhakim

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Introduction

• Terminology (including acronyms)
• Concepts and principles
• The underlying model
• Encapsulation
• End-to-end paradigm
• Naming and addressing
• Functions of protocols including Address
  Resolution Protocol (ARP), IP, TCP, UDP,SMTP,
  FTP, DHCP, and more

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Introduction

• Layering model
• What do you understand about layering
• Give an example
• Internet architecture and routing
• Homework, find the Internet Architecture
• Present in class
• Applications
• www
• Email and etc

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What Is an Internetwork?

• An internetwork is a collection of individual
  networks, connected by intermediate networking
  devices, that functions as a single large
  network.

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Internetworking

• Internetworking (cisco)
• refers to the industry, products, and procedures
  that meet the challenge of creating and
  administering internetworks.
• Internetworking Douglas E. Comer
• an overview of concepts, terminology, and
  technology underlying the TCP/IP Internet
  protocol suite and the architecture of an
  internet.

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Why Study TCP/IP?

• Before TCP/IP and the Internet
• Two sources of network protocols
• Specific vendors such as IBM or Digital Equipment
• Standards bodies such as the ITU (formerly known
  as CCITT)
• TCP/IP
• Vendor independence

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Why Study TCP/IP?

• The Internet is everywhere
• What is Internet
• What do you understand everywhere
• Most applications are distributed
• Give an examples

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Who Built TCP/IP?

• Internet Architecture Board (IAB)
• Originally known as Internet Activities Board
• Evolved from Internet Research Group
• Forum for exchange among researchers
• About a dozen members
• Reorganized in 1989 and 1993
• Merged into the Internet Society in 1992

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Components Of The IAB Organization

• Internet Architecture Board (IAB)
• Board that oversees and arbitrates
• URL is
• http//www.iab.org/iab
• IRTF (Internet Research Task Force)
• Coordinates research on TCP/IP and
  internetworking
• Virtually defunct, but may re-emerge
• URL
• http//www.irtf.org/

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Components Of The IAB (continued)

• IETF (Internet Engineering Task Force)
• Coordinates protocol and Internet engineering
• Headed by Internet Engineering Steering Group
  (IESG)
• Divided into N areas (N is 10 plus or minus a
  few)
• Each area has a manager
• Composed of working groups (volunteers)
• URL is
• http//www.ietf.org

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ICANN

• Internet Corporation for Assigned Names and
  Numbers
• http//www.icann.org
• Formed in 1998 to subsume IANA contract
• Not-for-profit managed by international board
• Now sets policies for addresses and domain names
• Support organizations
• Address allocation (ASO)
• Domain Names (DNSO)
• Protocol parameter assignments (PSO)
• http//www.icannwatch.org/

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World Wide Web Consortium

• Organization to develop common protocols for
  World Wide Web
• Open membership
• Funded by commercial members
• URL is http//w3c.org

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Internet Society

• Organization that promotes the use of the
  Internet
• Formed in 1992
• Not-for-profit
• Governed by a board of trustees
• Members worldwide
• URL is http//www.isoc.org

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Protocol SpecificationsAnd Documents

• Protocols
• A protocol is a formal set of rules and
  conventions that governs how computers exchange
  information over a network medium.
• documented in series of reports
• Example Network protocol, routing protocol, etc.
• Documents known as Request For Comments (RFCs)
• Anyone know about RFCs

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RFCs

• Series of reports that include
• TCP/IP protocols
• The Internet
• Related technologies
• Edited by IESG (Eng Steering group), but not
  peer-reviewed like scientific journals
• Contain
• Proposals
• Surveys and measurements
• Protocol standards
• Numbered in chronological order

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RFCs (continue)

• Host Requirements Documents
• Major revision/clarification of most TCP/IP
  protocols
• RFC 1122 (Communication Layers)
• RFC 1123 (Application Support)
• RFC 1127 (Perspective on 1122-3)
• Router Requirements
• Major specification of protocols used in IP
  gateways
• (routers)
• RFC 1812 (updated by RFC 2644)

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Internet Drafts

• Preliminary RFC documents
• Often used by IETF working groups
• Either become RFCs within six months or disappear
• Available via
• Email
• FTP
• World Wide Web
• http//www.ietf.org/

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• Questions?

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History of Internetworking

• IBMs Systems Network Architecture (SNA) and
  Digitals network architecture.
• time-sharing networks that used mainframes and
  attached terminals.
• Local-area networks (LANs)
• relatively small geographical area to exchange
  files and messages
• shared resources
• such as file servers and printers.
• Wide-area networks (WANs)
• interconnect LANs with geographically dispersed
  users to create
• connectivity.
• High-speed LANs and switched internetworks
• operate at very high speeds and support such
  high-bandwidth applications as multimedia and
  videoconferencing.

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Open System Interconnection Reference Model

• The Open System Interconnection (OSI) reference
  model describes how information from a software
  application in one computer moves through a
  network medium to a software application in
  another computer.
• Divides the tasks involved
• Each layer is reasonably self-contained
• implemented independently.
• enables the solutions offered by one layer to be
  updated without adversely affecting the other
  layers

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The OSI Reference Model Contains Seven
Independent Layers
Upper layer (Application Layer) - Implemented
only in software
Lower layer (Data transport Layer) - Implemented
both in hardware and software
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OSI Model Layers Communicate with Other Layers
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Service Users, Providers, and Service Access
Points (SAPs) Interact at the Network and Data
Link Layer

• One OSI layer communicates with another layer to
  make use of the services
• The services help a given OSI layer communicate
  with its peer layer in other computer systems.
• Three basic elements are involved in layer
  services
• the service user,
• the service provider, and
• the service access point (SAP).

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Service Users, Providers, and Service Access
Points (SAPs) Interact at the Network and Data
Link Layer

• Service user is the OSI layer that requests
  services from an adjacent OSI layer.
• Service provider is the OSI layer that provides
  services to service users. OSI layers can provide
  services to multiple service users.
• The SAP is a conceptual location at which one OSI
  layer can request the services of another OSI
  layer.

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Service Users, Providers, and Service Access
Points (SAPs) Interact at the Network and Data
Link Layer
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Chapter 2 Review of Underlying Network
Technologies
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Basic Network Concept

• The TCP/IP Concept (Five layers
• Network hardware
• Connection-oriented
• Connectionless
• Packet Switching Networks
• Local Area Network (LAN)
• Wide Area Network (WAN)
• Point-to-point link
• Set of bridged networks

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Two Basic CategoriesOf Network Hardware

• Connection oriented (circuit switching)
• establish a connection with the desired service
  before passing any data
• Operate by forming a dedicated connection or
  circuit between 2 points
• Paradigm
• Form a connection through the network
• Send / receive data over the connection
• Terminate the connection
• Involves 3 phases connection establishment, data
  transfer, and connection termination

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Connection oriented

• Can guarantee bandwidth
• Dedicated circuit, 64 Kbps,128 Kbps, 1M, 2M etx.
• monitor for lost packets and handle resending
  them
• The protocol is generally also responsible for
  putting the packets in the right sequence before
  passing the data up the protocol stack
• negotiate a connection, transfer data, and tear
  down the connection
• Proponents argue that it works well with
  real-time applications
• Independent use

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Connection oriented

• Can guarantee bandwidth
• Dedicated circuit, 64 Kbps,128 Kbps, 1M, 2M etx.
• monitor for lost packets and handle resending
  them
• The protocol is generally also responsible for
  putting the packets in the right sequence before
  passing the data up the protocol stack
• negotiate a connection, transfer data, and tear
  down the connection
• Proponents argue that it works well with
  real-time applications
• Independent use

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Connectionless(Packet Switched Technology)

• Paradigm
• Form packet of data
• Pass to network
• (Data to be transferred across a network is
  divided into small pieces called packed that are
  multiplexed onto high capacity inter-machine
  connections)
• Each packet travels independently
• transfer can simply send the data without the
  added overhead of creating and tearing down a
  connection
• Packet includes identification of the destination
• Enables the network hardware to know how to send
  it to specific destination
• Each packet can be a different size
• The maximum packet size is fixed (some
  technologies limit packet sizes to 1,500 octets
  or less)

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Connectionless

• Advantage
• Multiple communication among computers can
  proceed at the simultaneously with intermachine
  connection shared by all pairs of computer that
  are communicating
• Disadvantage
• Overloaded the networks computers must wait
  before sending additional packets

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Broad Characterizations OfPacket Switching
Networks

• Local Area Network (LAN)
• Engineered for
• Low cost
• High capacity
• Direct connection among computers
• Limited distance
• Wide Area Network (WAN)
• Engineered for
• Long distances
• Indirect interconnection via special-purpose
  hardware
• Higher cost
• Lower capacity (usually)
• Categories are informal and qualitative

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Local Area Networks

• What is LAN
• A LAN is a high-speed data network that covers a
  relatively small geographic area. It typically
  connects workstations, personal computers,
  printers, servers, and other devices. .
• Engineered for
• Low cost
• High capacity
• Direct connection among computers
• Limited distance
• LANs offer computer users many advantages,
  including shared access to devices and
  applications, file exchange between connected
  users, and communication between users via
  electronic mail and other applications

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Three LAN Implementations Are Used Most Commonly
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Wide Area Networks(Long Haul Networks)

• What is WAN
• A WAN is a data communications network that
  covers a relatively broad geographic area and
  that often uses transmission facilities provided
  by common carriers, such as telephone companies.
• WAN technologies generally function at the lower
  three layers of the OSI reference model the
  physical layer, the data link layer, and the
  network layer
• Engineered for
• Long distances
• Indirect interconnection via special-purpose
  hardware
• Higher cost
• Lower capacity (usually)

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A Typical Point-to-Point Link Operates Through a
WAN to a Remote Network
http//www.cisco.com/univercd/cc/td/doc/cisintwk/i
to_doc/
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Examples Of PacketSwitched Networks

• Wide Area Nets
• ARPANET, NSFNET, ANSNET
• Common carrier services
• Leased line services
• Point-to-point connections
• Local Area Nets
• Ethernet
• Wi-Fi

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ARPANET (1969-1989)

• Original backbone of Internet
• Wide area network around which TCP/IP was
  developed
• Funding from Advanced Research Project Agency
• Initial speed 50 Kbps

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NSFNET (1987-1992)

• Funded by National Science Foundation
• Motivation Internet backbone to connect all
  scientists and engineers
• Introduced Internet hierarchy
• Wide area backbone spanning geographic U.S.
• Many mid-level (regional) networks that attach to
  backbone
• Campus networks at lowest level
• Initial speed 1.544 Mbps

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ANSNET (1992-1995)

• Backbone of Internet before commercial ISPs
• Typical topology

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Abilene Network Backbone
Current status of the Abilene network at 10Gbps.
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Wide Area Networks AvailableFrom Common Carriers

• In telecommunications, T-carrier, sometimes
  abbreviated as T-CXR, is the generic designator
  for any of several digitally multiplexed
  telecommunications carrier systems originally
  developed by Bell Labs and used in North America,
  Japan, and Korea.
• Optical Carrier levels describe a range of
  digital signals that can be carried on
  Synchronous optical networking SONET fiber optic
  network.1 The number in the Optical Carrier
  level is directly proportional to the data rate
  of the bitstream carried by the digital signal.
• The general rule for calculating the speed of
  Optical Carrier lines is when a specification is
  given as OC-n, that the speed will equal n 51.8
  Mbit/s.2

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Wide Area Networks AvailableFrom Common Carriers

• Point-to-point digital circuits
• T-series (e.g., T1 1.5 Mbps, T3 45 Mbps)
• OC-series (e.g., OC-3 155 Mbps, OC-48 2.4
  Gbps)

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Wide Area Networks AvailableFrom Common Carriers
(cont.)

• OC-1 (Optical) (1) STS1 on Optical
  facilitiesOC-3 (3) OC-1s 155.52mbits/secOC-9
  (9) OC-1s (not commonly used)
  466.56mbits/secOC-12 (12) OC-1s or (4) OC-3s
  622.08mbits/secOC-18 (18) OC-1s (not commonly
  used) 933.12mbits/secOC-24 (24) OC-1s (not
  commonly used) 1.244gbits/secOC-36 (36)
  OC-1s (not commonly used) 1.866gbits/secOC-48
  (48) OC-1s or (4) OC-12s or (16) OC-3s
  2.488gbits/secOC-192 (192) OC-1s or (4) OC-48s
  or (16) OC-12s or (64) OC-3s 9.953gbits/sec
• OC-256 13.271 Gbps
• OC-768 40 Gbps
• What is the latest OC ??? New DWDM systems are
  now in development to run at at 10 trillion bits
  per second (10 Tbps) per fiber.

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Wide Area Networks AvailableFrom Common Carriers
(Cont)

• Packet switching services also available
• The size of network can be extended by adding a
  new switch and another communication lines
• The larger the WAN becomes the longer it takes to
  route traffic across it
• Examples ISDN, SMDS, Frame Relay, ATM

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2.4 EthernetA Brief History

• The original Ethernet was developed as an
  experimental coaxial cable network in the 1970s
  by Xerox Corporation to operate with a data rate
  of 3 Mbps using a carrier sense multiple access
  collision detect (CSMA/CD) protocol for LANs with
  sporadic but occasionally heavy traffic
  requirements. Success with that project attracted
  early attention and led to the
• 1980 joint development of the 10-Mbps Ethernet
  Version 1.0 specification by the three-company
  consortium Digital Equipment Corporation, Intel
  Corporation, and Xerox Corporation.
• The original IEEE 802.3 standard was based on,
  and was very similar to, the Ethernet Version 1.0
  specification. The draft standard was approved by
  the 802.3 working group in 1983 and was
  subsequently published as an official standard in
  1985 (ANSI/IEEE Std. 802.3-1985). Since then, a
  number of supplements to the standard have been
  defined to take advantage of improvements in the
  technologies and to support additional network
  media and higher data rate capabilities, plus
  several new optional network access control
  features.

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EthernetA Brief History

• Coaxial Cable Original Wiring Scheme
• Twisted Pair Ethernet Cat 5 (Because existing
  telephone wires uses same technology) Cheaper
  and easier to install as compared to coaxial
  cable.

Category 6 cable, commonly referred to as Cat 6,
is a cable standard for Gigabit Ethernet and
other network protocols that is backward
compatible with the Category 5/5e and Category 3
cable standards. Cat-6 features more stringent
specifications for crosstalk and system noise.
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2.4.2 Fast and Gigabit Ethernet

• Extremely popular
• Packet-switched LAN tech
• Can run over
• Copper (twisted pair)
• Optical fiber
• Three generations
• 10Base-T operates at 10 Mbps (also depends on the
  Network Bandwidth)
• To overcome the throughput problem - same wires
  at Cat 5, but achieve more bandwidth by using
  more wires
• 100Base-T (fast Ethernet) operates at 100 Mbps
• 10/100 Ethernet (dual speed Ethernet)
• 1000Base-T (gigabit Ethernet) operates at 1 Gbps
• 1000 Base-X (fiber optics Ethernet signals are
  converted to light pulses) 10 40 Gbps

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2.4.2 Fast and Gigabit Ethernet

• Technology known as 10/100/1000 Ethernet is
  available for NICs as well as for switches.
• Automatic negotiation and determination of the
  cables and maximum speed the other side of the
  connection can support

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2.4.2 Fact for the Day !

• 10BASE-T, one of several physical media specified
  in the IEEE 802.3 standard for Ethernet local
  area networks (LANs), is ordinary telephone
  twisted pair wire.
• 10BASE-T supports Ethernet's 10 Mbps
  transmission speed. In addition to 10BASE-T, 10
  megabit Ethernet can be implemented with these
  media types

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2.4.2 Fact for the Day ! (cont.)

• 10BASE-2 (Thinwire coaxial cable with a maximum
  segment length of 185 meters)
• 10BASE-5 (Thickwire coaxial cable with a maximum
  segment length of 500 meters)
• 10BASE-F (optical fiber cable)
• 10BASE-36 (broadband coaxial cable carrying
  multiple baseband channels for a maximum length
  of 3,600 meters)

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2.4.2 Fact for the Day ! (cont.)

• This designation is an Institute of Electrical
  and Electronics Engineers (IEEE) shorthand
  identifier.
• The "10" in the media type designation refers to
  the transmission speed of 10 Mbps.
• The "BASE" refers to baseband signalling, which
  means that only Ethernet signals are carried on
  the medium.
• The "T" represents twisted-pair the "F"
  represents fiber optic cable and the "2", "5",
  and "36" refer to the coaxial cable segment
  length (the 185 meter length has been rounded up
  to "2" for 200).

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Power over Ethernet

• Power over Ethernet (PoE) can send small amount
  of electrical power over the same copper cable
  used for Ethernet

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2.4.5 Properties of Ethernet

• Design for shared bus technology that supports
  broadcast
• All station connect to a single, shared
  communication channel
• Transmit a packet to all stations at the same
  time
• Single segments up to 500m with up to 4
  repeaters gives 2500m max length
• Max 100 stations/segment, 1024 stations/Ethernet
• Best effort delivery
• Hardware provide no information to the sender
  about whether the packet was delivered

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Properties of Ethernet

• CSMA/CD shared medium Ethernet
• Ethernet originally used a shared coaxial cable
  (the shared medium) winding around a building or
  campus to every attached machine. A scheme known
  as carrier sense multiple access with collision
  detection (CSMA/CD) governed the way the
  computers shared the channel. This scheme was
  simpler than the competing token ring or token
  bus technologies.

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Properties of Ethernet

• When a computer wanted to send some information,
  it used the following algorithm
• Main procedure
• Frame ready for transmission.
• Is medium idle? If not, wait until it becomes
  ready and wait the interframe gap period (9.6 µs
  in 10 Mbit/s Ethernet).
• Start transmitting.
• Did a collision occur? If so, go to collision
  detected procedure.
• Reset retransmission counters and end frame
  transmission.
• Collision detected procedure (aborts when it
  detects collisions)
• Continue transmission until minimum packet time
  is reached (jam signal) to ensure that all
  receivers detect the collision.
• Increment retransmission counter.
• Was the maximum number of transmission attempts
  reached? If so, abort transmission.
• Calculate and wait random backoff period based on
  number of collisions. (must wait for a minimum
  idle time)
• Re-enter main procedure at stage 1.

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2.4.7. Wireless Networks and Ethernet

• IEEE standards
• IEEE 802.11b Wi-Fi (max 11Mbps)
• IEEE 802.11a and 802.11g 54Mbps
• IEEE 802.16 WiMax IEEE802.n
• 540 Mbps and 802.11i (Security)
• Enables multiple users to share a broadband
  connection Supports WiFi 802.11 b/g Four
  RJ45 Local Area Network ports available
  Additional Home Voice Service Easy to use -
  plug and play Supports Windows 2000, XP and
  Vista only

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Topology
Example Coaxial Bus Topology -limited to 500
meter -100 stations
                                               
                                   
repeater
Hub/switch
Example Star-Connected Topology
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Ethernet Hardware Addresses

• 48-bit addressing scheme
• Each NIC card is assigned a unique 48-bit number
  known as an Ethernet Address
• How?
• Ethernet hardware manufacturers purchase blocks
  of Ethernet technologies and assign them in
  sequence.
• Physical addresses
• Recall, that when computers connect to a hub,
  each computer receives a copy of every packet
  sent

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Ethernet Frame Format

• Layer 2 thought of as link-level connection
• Header format fixed (Destination, Source, Type
  fields)
• Frame data size can vary from packet to packet
• Maximum 1518 octets
• Minimum 64 octets
• Preamble and CRC (Cyclic Redundancy Check)
  removed by framer hardware before
• frame stored in computers memory both sender
  and receiver calculate the CRCs and counter check
• Self Identifying (used by the OS to determine
  which protocol therefore a system can have many
  protocols)
• Determine which protocol software module should
  process the frame

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Example Ethernet Frame In Memory

• Octets shown in hexadecimal
• Destination is 02.07.01.00.27.ba
• Source is 08.00.2b.0d.44.a7
• Frame type is 08.00 (IP)

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Point-to-Point Network

• Any direct connection between two computers
• Leased line
• Connection between two routers
• Dialup connection
• Link-level protocol required for framing
• TCP/IP views as an independent network

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Bridge

• Hardware device that connects multiple LANs and
  makes them appear to be a single LAN
• Repeats all packets from one LAN to the other and
  vice versa (does not replicate noise, errors or
  malformed frames must be valid frame)
• Introduces delay of 1 packet-time
• Does not forward collisions or noise
• Called Layer 2 Interconnect or Layer 2 forwarder
• Makes multiple LANs appear to be a single, large
  LAN
• Often embedded in other equipment (e.g., DSL
  modem)
• Watches packets to learn which computers are on
  which
• side of the bridge (adaptive bridges)
• Uses hardware addresses to filter

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Layer 2 Switch

• Electronic device
• Computers connect directly
• Applies bridging algorithm
• Can separate computers onto virtual networks
  (VLAN switch)

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Local and Remote Bridges Connect LAN Segments in
Specific Areas
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Bridging Switching

• Function
• controls data flow, handles transmission errors,
  provides physical (as opposed to logical)
  addressing, and manages access to the physical
  medium.
• by using various link layer protocols that
  dictate specific flow control, error handling,
  addressing, and media-access algorithms
• Task
• analyze incoming frames, make forwarding
  decisions based on information contained in the
  frames, and forward the frames toward the
  destination

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ATM Asynchronous Transfer Mode

• Asynchronous Transfer Mode (ATM) is a cell relay,
  packet switching network and data link layer
  protocol which encodes data traffic into small
  (53 octets 48 octets of data and 5 octets of
  header information) fixed-sized cells. ATM
  provides data link layer services that run over
  Layer 1 links. This differs from other
  technologies based on packet-switched networks
  (such as the Internet Protocol or Ethernet), in
  which variable sized packets (known as frames
  when referencing Layer 2) are used.

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Physical Networks AsViewed By TCP/IP

• TCP/IP protocols accommodate
• Local Area Network
• Wide Area Network
• Point-to-point link

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INTERNETWORKING CONCEPT

• Content
• Properties of Internetworking
• Network Interconnection
• Physical connectivity

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Accommodating Heterogeneity

• Application gateways
• Gateway forwards data from one network to another
• Step at a time
• Disadvantage

1. Limited Communication
2.Unrealiable communication
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Network level Interconnection

• Network-level gateways
• Delivers small packets of data from their
  original source to their ultimate destination
  without using intermediate application program
• Gateway forwards individual packets
• Advantage

1.Efficient directly mapping
2.Separate data comm. activities
3. Flexible system
4.Unlimited communication
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Desired Design Properties

• Universal service
• End-to-end connectivity
• Transparency

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Agreement Needed ToAchieve Desired Properties

• Data formats
• Procedures for exchanging information
• Identification
• Services
• Computers
• Applications
• Broad concepts naming and addressing