1. How to use the Internet Ikjun Yeom

2. How to send a packet  buy a computer  make sure that the computer is equipped with a network interface card  find a place where the computer can be hooked up to the Internet  configure network setting properly  write a client-server program for sending and receiving a packet  run your server program on the destination  run your client program to send a packet

3. Network Settings  IP address – can be configured manually – or can be configured automatically by DHCP  subnet mask  default gateway  DNS server

4. Sample Code - Server

6. Sample Code - Client

8. How does a packet reach to a destination in the Internet? Internet ISP IAP

9. Name Resolution  URL to IP address  Using Domain Name Service Top Domain.kr.com.net.ac.kr.co.kr.skku.ac.kr.naver.com

10. Subnet Default Gateway

11. Address Resolution  mapping an IP with a MAC address  ARP (Address Resolution Protocol)

12. Routing  Intra-domain routing – RIP – IGRP – OSPF  Inter-domain routing – BGP iBGP eBGP