1 / 11

Address Resolution Protocol (ARP)

Address Resolution Protocol (ARP). 1A-2F-BB-76-09-AD. LAN (wired or wireless). 71-65-F7-2B-08-53. 58-23-D7-FA-20-B0. 0C-C4-11-6F-E3-98. LAN Addresses and ARP. Each adapter on LAN has unique LAN address. Broadcast address = FF-FF-FF-FF-FF-FF. = adapter. LAN Address (more).

helga
Download Presentation

Address Resolution Protocol (ARP)

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. Address Resolution Protocol(ARP)

  2. 1A-2F-BB-76-09-AD LAN (wired or wireless) 71-65-F7-2B-08-53 58-23-D7-FA-20-B0 0C-C4-11-6F-E3-98 LAN Addresses and ARP Each adapter on LAN has unique LAN address Broadcast address = FF-FF-FF-FF-FF-FF = adapter

  3. LAN Address (more) • MAC address allocation administered by IEEE • manufacturer buys portion of MAC address space (to assure uniqueness) • Analogy: • MAC address: like Social Security Number • IP address: like postal address • MAC flat address ➜ portability • can move LAN card from one LAN to another • IP hierarchical address NOT portable • depends on IP subnet to which node is attached

  4. IP Address 0 23 24 31 • IP address format Network ID Host ID • Multicast Address • 224.0.0.0 to 239.255.255.255 • Private address • 10.0.0.0 ~ 10.255.255.255 (10/8 prefix) • 172.16.0.0 ~172.31.255.255 (172.16/12 prefix) • 192.168.0.0 ~ 192.168.255.255 (192.168/16 prefix) • Special address

  5. data CRC type 6 6 2 64-1500 4 dst src

  6. IP Address/Physical Address • Static Mapping • IP broadcast address maps to Ethernet broadcast address) • IP Multicast Address maps to Ethernet Multicast Address • lower 23bits of class D IP map into the lower 23bits of Ethernet address 01:00:5e:00:00:00 • Dynamic Mapping • ARP • RARP

  7. ARP • Address Resolution Protocol • RFC-826 • Mapping between IP address and the physical address(such as MAC)

  8. ARP/RARP Packet Format 0 16 31 proto type hard type HLEN op PLEN sender ethernet address sender ether addr sender IP addr target ether addr sender IP addr target ethernet address target IP address Hardware type = 1 : Ethernet Protocol type = 080016: IP address HLEN: hardware address length = 6 : Ethernet MAC address length PLEN: protocol address length = 4 : IP address length OP(operation): 1: ARP request, 2: ARP response, 3: RARP request, 4: RARP response

  9. How it works ? To :140.113.25.6  ‚ ARP IP … ƒ Ethernet † (broadcast) „ Ethernet Ethernet ARP ARP IP 140.113.25.6

More Related