Exercise 1. Tools

Read the man pages for

• arp(8),
• ifconfig (if on Unix) or ipconfig (if on Windows),
• netstat(1),
• ping(8),
• whois(1),
• traceroute(8) or tracert on Windows.

Experiment running them and interpreting their output. Note that the University firewall prevents ICMP from escaping the university network. Investigate using the looking glasses at http://www.traceroute.org/.

Implement basic ping and traceroute functionality in a language of your choice.

Exercise 2. Packets

Read the man pages for tcpdump. Experiment running it to observe

• different ICMP exchanges,
• traceroute operation (increasing TTLs, &c),
• behaviour when you unplug/replug your network interface,
• TCP connection establishment and teardown,
• TCP retransmission of both SYNs and data,
• TCP self-clocking behaviour (ackno, seqno relationships).

Using tcpdump capture a reasonable duration period of network traffic. In a language of your choice, implement code to parse the resulting PCAP file, reassembling data successfully transferred in all TCP flows (i.e., ignore retransmissions). Print statistics concerning flow duration, size, bandwidth, loss.

If you find yourself unable to run tcpdump directly, consider using some publicly available dataset from, e.g., Crawdad, or the UMass Trace Repository.

Iain Fraser has kindly taken some traces as directed above for reference: the parsed traces are here.

Exercise 3. Routes

Using (or implementing!) a library of your choice, examine routing data held by the RouteViews or RIPE/RIS projects. Suggestions

• extract and plot BGP dynamics for given prefixes (withdraw/update),
• extract and plot behaviour over time of the AS_PATH attribute and its manipulation,
• reconstruct the RIBs and FIBs that would pertain at any point,
• extract and plot the evolution of the Internet’s AS structure.

References: PyRT

Exercise 4. Web services

Implement a simple base-N encode/decode RESTful webservice that limits a given user to 10 operations and is resilient to client failure. Do not use any system, runtime or third-party libraries that directly provide either base-N encoding or UUID generation. As a minimum, support N=64, 32, 16.

References: RFC4122, RFC4648.

General

These books are good general background textbooks on computer communications. They all cover material from the course, much of which will be in more detail or with more examples than we have time to go into during lectures.

Network Algorithmics

Network Algorithmics: An Interdisciplinary Approach to Designing Fast Networked Devices by George Varghese, Morgan-Kaufman, 2004. ISBN 978-0-12-088477-3.

Interconnections

Interconnections (2nd ed.): bridges, routers, switches, and internetworking protocols, by Radia Perlman, Addison-Wesley Longman Publishing Co., Inc, 2000. ISBN 0-201-63448-1.

Top-Down Approach

Computer Networking: A Top-Down Approach, 4th Edition by Jim Kurose and Keith Ross, 2007.

A Systems Approach

Computer Networks - A Systems Approach, 4th Edition by Larry L. Peterson and Bruce S. Davie, Morgan Kaufmann, 2007.

Stallings

Data and Computer Communication Networks, sixth edition by William Stallings, Prentice Hall, 2011. ISBN: 978-0-13-139205-2.

Topic Specific

These books provide more detail on particular elements covered within the course.

UNIX Network Programming

UNIX Network Programming, Volume 1: The Sockets Networking API, 3rd Edition by W. Richard Stevens, Bill Fenner, and Andrew M. Rudoff, Addison-Wesley, 2003. See also Volume 2: Interprocess Communications.

TCP/IP Illustrated

TCP/IP Illustrated, Volume 1: The Protocols, by W. Richard Stevens. See also Volume 2: The Implementation and Volume 3: TCP for Transactions, HTTP, NNTP, and the UNIX Domain Protocols.

Internetworking

Internetworking With TCP/IP Volume 1: Principles Protocols, and Architecture, 5th edition by Douglas Comer, Prentice-Hall, 2006. ISBN 0-13-187671-6. See also Volume 2: Design, Implementation and Internals and Volume 3: Client-Server Programming and Applications (different editions for different specific platforms).

Internet Administration

• The Internet Assigned Numbers Authority, IANA manages Internet number allocations such as TCP/UDP ports and IP address blocks.
• The Internet Engineering Task Force, IETF documents and standardises Internet protocols, primarily through the Internet Requests for Comment, RFCs series, which subsumed the Internet Engineering Notes, IENs (mirror).
• The North American Network Operators Group, NANOG is the community of network admins, predominantly for Internet providers based in North America.

Related Courses

• University of Berkeley, Introduction to Communication Networks EE122 (2009) EE122 (2010)
• University of Berkeley, Graduate Computer Networks CS268 (2003)
• University of Cambridge, Network Architecture (primarily a paper-reading/research based course).

Miscellaneous

• Several of the major network-vendor websites have informative data sheets, product specs and manuals. Among the major players are Cisco Juniper Extreme Avaya and Brocade.

• routergod.com is a bit of fun.