L2 - Internet Addressing and Naming CS 7260 Nick Feamster...

Info iconThis preview shows pages 1–12. Sign up to view the full content.

View Full Document Right Arrow Icon
Internet Addressing and Naming CS 7260 Nick Feamster January 10, 2007
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 Announcements Course mailing list cs7260-course at mailman.cc.gatech.edu https://mailman.cc.gatech.edu/mailman/listinfo/cs7260-course Wiki should be up soon (we hope) TA: Keshav Attrey (attrey@cc.gatech.edu)
Background image of page 2
3 Today: Addressing and Naming Internet Addressing Step 1: Connecting a single network Step 2: Connecting networks of networks IPv4 Addressing – Structure – Scaling problems and CIDR (1994) Allocation and ownership – Longest prefix match and Traffic Engineering Issues and design questions More scaling problems and solutions Internet Naming Today: DNS and the naming hierarchy Research: Flat names Paper discussion: Jung et al.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
4 Bootstrapping: Networks of Interfaces LAN/Physical/MAC address Unique to physical interface (no two alike) Flat structure sender frame receiver datagram frame adapter adapter link layer protocol What are the advantages to separating network layer from MAC layer? Frames can be sent to a specific MAC address or to the broadcast MAC address
Background image of page 4
5 ARP: IP Addresses to MAC addresses Query is IP address, response is MAC address Query is sent to LAN’s broadcast MAC address Each host or router has an ARP table Checks IP address of query against its IP address Replies with ARP address if there is a match Potential problems with this approach? Caching is key! Try arp –a to see an ARP table
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
6 Interconnecting LANs: Bridging Learning Spanning tree (RSTP, MSTP, etc.)
Background image of page 6
7 Learning Bridges Bridge builds mapping of which port to forward packets for a certain MAC address LAN A LAN B LAN C A B C If has entry, forward on appropriate port If no entry, flood packet Potential problems with this approach?
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
8 Virtual LANs (VLANs) A single switched LAN can be partitioned into multiple “colors” Each color behaves as a separate LAN Better scaling properties Reduce the scope of broadcast storms Spanning tree algorithms scale better Better security properties
Background image of page 8
9 IPv4 Addresses: Networks of Networks 32-bit number in “dotted-quad” notation www.cc.gatech.edu --- 130.207.7.36 10000010 11001111 00000111 00100100 Network (16 bits) Host (16 bits) 130 207 7 36 Problem: 2 32 addresses is a lot of table entries Solution: Routing based on network and host 130.207.0.0/16 is a 16-bit prefix with 2 16 IP addresses Topological Addressing
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
10 Pre-1994: Classful Addressing Network ID Host ID 8 16 Class A 32 0 Class B 10 Class C 110 Multicast Addresses Class D 1110 Reserved for experiments Class E 1111 24 /8 blocks ( e.g. , MIT has 18.0.0.0/8) /16 blocks ( e.g. , Georgia Tech has 130.207.0.0/16) /24 blocks ( e.g. Simple Forwarding: Address range specifies network ID length
Background image of page 10
11 Problem: Routing Table Growth Growth rates exceeding advances in hardware and
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 12
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 50

L2 - Internet Addressing and Naming CS 7260 Nick Feamster...

This preview shows document pages 1 - 12. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online