Computer Network

Only available on StudyMode
  • Download(s) : 115
  • Published : April 21, 2011
Open Document
Text Preview

Introduction to Computer Networking
Prof. Jean-Yves Le Boudec Prof. Andrzej Duda Prof. Laurent Toutain Prof. Patrick Thiran ICA, EPFL CH-1015 Ecublens


o understand TCP/IP and networking terminology
l l l l l l l l l l

layered model transport protocol TCP; UDP; IP; MAC IP addresses, MAC addresses,machine names, DNS, NetBIOS names, port numbers routers, bridges, servers client server architecture HTTP, FTP, SMTP multiplexing and switching protocol connection

o basic elements of transmission


o useful complement to these notes
[Stevens] “TCP/IP illustrated volume I”, The protocols, W. Richard Stevens, Addison Wesley Very detailed, experimental hands-on description of TCP/IP. Also volume III for HTTP

[STA] “High Speed Networks (TCP/IP and ATM Design Principles”, William Stallings, Prentice Hall, 1997 Advanced topics

[Keshav] “An Engineering Approach to Computer Networking”, S. Keshav, Addison Wesley, 1998 Advanced topics

[Kurose, Ross] “Computer Networking”, J.F. Kurose and K.W. Ross, Addison Wesley, 2000 Top down approach, applications

o other references
[Walrand and Varaiya] High Performance Communication Networks, Jean Walrand and Pravin Varayia, Morgan Kaufman, http// [BG] “Data Networks”, Dimitri Bertsekas and Robert Gallager, Prentice Hall Theoretical approach, fundamentals ideas behind basic building b locks of a computer network. Little description of real systems


Network Services
o network services examples:

distributed database, Web (3) , file transfer, remote login, email, news, talk, remote processing, resource sharing (file servers, printers, modems), network time, name service (2) ……

user clicks: name server 1 2 query

answer IP addr = Web server IP addr = GET activities.html


data (HTML page)

In this lecture we study computer networks. We use a top-down approach, starting with applications. We present an overall picture, which will enable you to understand the layered model of networking software. Then in the following chapters, we will study the various components (called “layers”), one by one. What are computer networks used for ? Computer networks allow people and machines to communicate, using a number of services. The slide shows a small subset of services.


Network Infrastructure
A computer network is made of o distributed applications
l l

provide services to users on other machines, or to other machines execute on computers supports transport of data between computers where distributed applications reside in computers (Ethernet card, modem + software) + in special network devices (bridges, routers, concentrators, s witches)

o network infrastructure
l l

focus of this lecture = network infrastructure

A computer network is made of two distinct subsets of components - distributed applications are programs running on interconnected computers; a web server, a remote login server, an e-mail exchanger are examples. This is the visible part of what people call “the Internet”. In this lecture we will study the simplest aspects of distributed applications. More sophisticated aspects are the object of lectures called “Distributed Systems” and “Information Systems”. - the network infrastructure is the collection of systems which are required for the interconnection of computers running the distributed applications. It is the main focus of this lecture. The network infrastructure problem has itself two aspects: - distance: interconnect remote systems that are too far apart for a direct cable connection - meshing: interconnect systems together; even in the case of systems close to each other, it is not possible in non-trivial cases to put cables from all systems to all systems...
tracking img