Brandeis CS 146a

ASSIGNMENT 6: October 20 through October 27, 2011

For Class, Monday, October 25, 2011

Class Discussion

The discussion today will be on Network Address Translation. Please read "Anatomy: a Look Inside Network Translations" by Geoff Huston .

You may also want to check out these relevant documents.

Architectural Implications of NAT (RFC 2993)
IP Network Address Translator (NAT) Terminology and Considerations (RFC 2663)
Protocol Complications with the IP Network Address Translator (NAT) (RFC 3027)
Internet Transparency (RFC 2775)
Classless Inter-Domain Routing (CIDR) (RFC 1519)

M. Walfish, et al., "Middleboxes No Longer Considered Harmful" 6th Usenix OSDI, San Francisco, CA, December 2004.

Address the following reading question:

Recall from prior lecture/discussions that to increase routing scalability, IP addresses are hierarchically allocated (i.e., the Internet uses variable-length "area identifiers"). How does the hierarchical allocation affect the address shortage problem? Is the IP address space efficiently used?
What are the characteristics of a global address? What are the characteristics of a local/private address?
Why do global addresses have to be different from local addresses? What happens if a NAT box advertises a local IP addresses (e.g., 10.*.*.*) to the rest of the Internet?

Lecture Material:

Our lecture topic today is scalable lookup, we will talk about DNS and peer-to-peer systems. Read about Domain Name System (the Internet's name system). from Chapter 4 Appendix A and also browse the RFC1032 man pages of 'Named' - they describe the Internet Domain name server.

For Class Wednesday, October 27, 2011

There is no lecture today. Instead, we will run a Q&A session to help you get started on Project 2.

CS146a, Assignment 6, issued 10/20/2011