ECS 152B

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• ECS 152B
• Computer Networks
• Demet Aksoy
• http//www.cs.ucdavis.edu/aksoy/courses/s06

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Information

• Lectures- MWF 1210-100, 146 Olson
• Discussion- F 210-330, 147 Olson
• Prerequisites
• ECS150 and ECS152A
• Make sure to follow up the announcements at
• www.cs.ucdavis.edu/aksoy/course/s06/152b.html
• ucd.class.ecs152b
• ucd.class.ecs152b.d

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Grading Policy

• Grading
• Projects 30 (2 projects, 1020)
• Midterm 20 (one mid-term)
• Homework 15 (2-3 sets)
• Final 35
• Midterm DateApril 28, 2006 146 Olson
• Final DateSat, June 10, 800-1000 a.m. 146
  Olson
• Late policy
• Will not be graded unless approved in advance by
  the instructor
• Regrading Policy
• One week regrading period
• Academic Integrity

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Good Grade Guideline

• Protocol stacks are rational
• Understand, not memorize
• Active classroom participation
• Do your own homework
• Help you understand
• Help you do well in exams
• Hands-on project involvement
• Follow the announcements and handouts

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Information

• Course Resources
• http//www.cs.ucdavis.edu/aksoy/course/s06/152b.h
  tml
• Course Information
• http//www.cs.ucdavis.edu/aksoy/course/s06/info.h
  tml
• Course Outline
• http//www.cs.ucdavis.edu/aksoy/course/s06/outlin
  e.html

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Road Map

• I. Introduction
• Computer Networks Overview
• Protocols
• Layered architecture
• II. IP Protocols
• Internet Protocol
• Routing protocols
• ICMP and IGMP
• III. Transport Layer
• UDP
• TCP

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Road Map

• IV. Transport Layer Interfaces
• Socket
• Socket related system calls
• I/O Multiplexing
• V. Networking Applications
• Network Library Routines
• File Transfer Protocol (FTP)
• HyperText Transfer Protocol (HTTP)
• Telnet / Remote Login
• Domain Name System (DNS)
• Remote Procedure Calls (RPC)
• VI. Additional Topics

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Whats a computer network
Interconnected collection of autonomous
computers attached to a host system
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Types of Networks

• Local Area Networks (LAN)
• restricted in size privately owned
• Metropolitan Area Networks (MAN)
• standardized distributed queue dual bus
• Wide Area Networks (WAN)
• subnets, packet switching nodes etc.
• Wireless Networks
• e.g., wireless LANs, not necessarily mobile
• Internetworks
• connecting different networks

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What is the Internet an application view

• Communication
• School, work, family, friend, spam, etc.
• Commerce
• ebay, amazon, travel, shopping, banking, ad, etc.
  
• Entertainment
• Music, movie, news, blog, etc.
• Make Billionaires
• Google, amazon, yahoo, ebay, etc.
• ....

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Cool internet appliances
IP picture frame http//www.ceiva.com/
What else?
Web-enabled toasterweather forecaster
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InterPlanetary Internet
Acknowledgement I. Akyildiz, Computer Networks,
2003
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Sensory Internet
Ack http//www.greatduckisland.net/ Ack I.
Akyildiz, Infocom 2005
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Whats the Internet nuts and bolts view

• millions of connected computing devices hosts,
  end-systems
• PCs, workstations, servers
• PDAs, phones, cars, sensors,
• running network apps
• communication links
• fiber, copper, radio, satellite
• transmission rate bandwidth
• routers forward packets (chunks of data)

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Whats the Internet

• protocols control sending, receiving of msgs
• e.g., TCP, IP, HTTP, FTP, PPP
• Internet network of networks
• loosely hierarchical
• public Internet versus private intranet
• Internet standards
• RFC Request for comments
• IETF Internet Engineering Task Force

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Whats the Internet a service view

• communication infrastructure enables distributed
  applications
• Web, email, games, e-commerce, database., voting,
  file (MP3) sharing
• Best-effort
• communication services provided to apps
• connectionless
• connection-oriented
• dynamic
• New applications are constantly being invented
  and deployed

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roadmap

• Computer Networks Overview
• 1 What is the Internet?
• 2 Network edge
• Client/Server Model
• Peer-to-Peer Model
• 3 Network core

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The network edge

• end systems (hosts)
• run application programs
• e.g. Web, email
• at edge of network
• client/server model
• client host requests, receives service from
  always-on server
• e.g. Web browser/server email client/server
• peer-peer model
• minimal (or no) use of dedicated servers, e.g.
  Gnutella, KaZaA, BT

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Client-server Paradigm

• Typical network app has two pieces client and
  server

• Client
• initiates contact with server (speaks first)
• typically requests service from server,
• for Web, client is implemented in browser for
  e-mail, in mail reader
• Server
• provides requested service to client
• e.g., Web server sends requested Web page, mail
  server delivers e-mail

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Acronym

• Standardization
• Internet Society (ISOC)
• Internet Architecture Board (IAB)
• Internet Engineering Task Force (IETF)
• Internet Research Task Force (IRTF)
• RFC
• Request for comments