1 / 26

TCOM 509 – Internet Protocols (TCP/IP) Lecture 01

TCOM 509 – Internet Protocols (TCP/IP) Lecture 01. Instructor: Dr. Li-Chuan Chen lichen@mitre.org TA: Waqar Ishaq wishaq@gmu.edu. Date: 08/25/2003. Based in part upon slides of Prof. J. Kurose (U Mass), Prof. B. Yener (Rensselaer Polytechnic Institute).

mikaia
Télécharger la présentation

TCOM 509 – Internet Protocols (TCP/IP) Lecture 01

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. TCOM 509 – Internet Protocols (TCP/IP)Lecture 01 Instructor: Dr. Li-Chuan Chenlichen@mitre.org TA: Waqar Ishaq wishaq@gmu.edu Date: 08/25/2003 Based in part upon slides of Prof. J. Kurose (U Mass), Prof. B. Yener (Rensselaer Polytechnic Institute)

  2. Topics - Tentative • Concepts Overview (1 lecture) • IP Protocol (2 lectures) • TCP/UDP (1 lecture) • Routing Protocols (1 lecture) • Internet Multicasting (1/2 lecture) • Application Protocols (1/2 lecture)

  3. Grading • Homeworks 30% • Midterm 30% • Final Exam 40% • Grades will be curved. • No late homeworks will be accepted.

  4. Outline • Introduction and Overview • Internetworking Concept and Architectural Model

  5. Internet: History • U.S. Department of Defense had multiple networks. • Advanced Research Projects Agency (ARPA) funded research on packet-switched networking. • Late 60’s - ARPANET went on-line with point-to-point leased line interconnection. • The goal was to interconnect all machines at different sites so that researchers could share data and their findings across the ARPANET. • ARPA researchers designed networking software called TCP/IP Internet Protocol Suite or TCP/IP in the mid 70’s.

  6. Internet: History • 1983 - Defense Communications Agency (DCA) mandates all computers connected to backbone Internet use TCP/IP. • 1983 - commercial implementation of TCP/IP begins. • ARPA reached over 90% of university computer science department by funding UC Berkeley to integrate TCP/IP into UNIX. • 1983-1993: Internet changed from a small experimental research project into the world’s largest computer network. • By late 1987, estimated the growth rate had reached 15% per month. By 2000, the global Internet reached over 50 million computers in 209 countries. Both the size and the use of the Internet continued to grow much faster than anticipated.

  7. Internet Host Count

  8. Exponential Web Growth Number of Web Sites: 1997: 1,570,000 1998: 2,851,000 1999: 4,882,000 2000: 7,399,000 2001: 8,745,000 Source: http://wcp.oclc.org/ Source: Network Wizards

  9. What are Internet Standards and RFC? • All activities on the Internet are governed by the Internet standards. • Who makes up these standards? • How they are organized? • Where to find these standards? • What is RFC?

  10. The Board IRSG IESG … area n area 1 … … … research groups working groups The Internet Architecture Board (IAB) • IAB decides which protocols are a required standard of the TCP/IP suite, sets official policies, and guides the evolution of the Internet. • Internet Research Task Force (IRTF) – coordinates research activities • Internet Engineering Task Force (IETF) – short-term and medium-term engineering problems The IAB Organization IRTF IETF

  11. What is RFC? • RFCs – Request For Comments • Most protocols of the TCP/IP are specified by RFCs • Internet Engineering Steering Group (IESG) edits and approves the RFCs. • RFCs publications are for the Internet community. • RFCs are published by the IAB and are freely available online. • Internet drafts are preliminary versions of RFC documents.

  12. Internet Services • Internet is a set of applications that use the underlying network to carry out communication tasks. Popular Internet application services are: • World Wide Web or Web allows users to view multimedia documents and to follow hyper links from one computer to another. • Electronic Mail or E-mail allows a user to compose and send messages to other individuals or groups on the Internet. • File Transfer application allows users to send or receive a coy of a data file. Will discuss these applications in greater detail later.

  13. Internet Services • Internet provides a connectionless or connection-oriented packet delivery service for transporting data across network. • Data is divided (fragmented) into smaller pieces called packets. Packets may take different routes from a given source to a given destination. • Connectionless • No guaranteed delivery of packets. Packets may arrive out-of-order. • Connection-oriented • Reliable transmission of packets delivery. Will retransmit packet if errors (transmission error, lost packets, hardware failure).

  14. The Problem • BeforeInternet: different packet-switching networks • Proprietary communication systems: only nodes on the same network could communicate.

  15. The Internetworking Problem • Two nodes, A and B, communicating across a cloud of networks • How to transportpackets through this heterogeneous networks? A B

  16. The Internetworking Problem • Problems: heterogeneous networks and systems, interoperability, and scalability • Heterogeneous networks and systems • How to interconnect a large number of disparate networks ? • How to support a wide variety of applications ? • Interoperability • How to interoperate between various vendors’ products? • Scalability • How to support a large number of end-nodes and applications in this interconnected network (Internet)?

  17. Internetworking Solution IP Gateways

  18. Definitions • A network is a collection of hosts and nodes (routers, switches, or gateways) interconnected by communication links. • Protocols are standards which specify the procedures for passing messages, the details of message formats and describe how to handle error conditions. • A gateway interconnects two disparate networks, translates protocols, and forwards packets from one to the other.

  19. Outline • Introduction and Overview • Internetworking Concept and Architectural Model

  20. Telnet FTP SMTP HTTP Optical fiber Coaxial cable PacketRadio Network-Level Interconnection • FTP – File Transfer Protocol • SMTP – Simple Mail Transfer Protocol • HTTP – World Wide Web protocol Application Transmission Media • Not scalable – Each new application has to be re-implemented for every transmission media.

  21. Telnet FTP SMTP HTTP Optical fiber Coaxial cable PacketRadio Network-Level Interconnection Application Internet Layer (IP) IP Transmission Media • Advantages • Efficient: mapping packets directly onto network media • Flexible: adding or modifying network software without the need for changing the application software. • Hides low-level details from the user.

  22. Properties of the Internet • Interconnects all computers by assigning a universal unique IP address. • Universal interconnection - allows any two nodes to communicate irrespective of their network architectures, network topologies, and distance.

  23. Internet Architecture Net 1 Net 2 R1 Net 3 R2 • A collection of cooperative, interconnected networks by IP gateways or routers (Ri). • IP routers provide interconnections among physical networks. • Routers use the destination network, not the destination computer, when forwarding a packet. • All networks are equal. A network can be a local area network (LAN), a wide area network (WAN), or a point-to-point link between two computers.

  24. Internet Architecture – User’s View internet hosts

  25. Internet Architecture hosts

  26. Internetworking Protocols

More Related