Hands-on Networking

My address, Other's address

• ipconfig or ifconfig is the PC/Unix/Mac utility program to find IP configurations

• nslookup is the utility to find other machines' name to address mapping

Layering

objective: why, what, where to find it

HW#0 First Trace

Install wireshark on your PC, capture and analyse a home page request to example.com

Check out the tools page on this site.

Submit one page that describes what you have captured and raise any questions you have on canvas discussions.

1. how do you get destination address? how do you get your address or do you see one? why or why not?

2. what's the sequence of request going out of your machine that's related to your browsing action?

3. how does the request related to layering?

4. what's the difference between DNS request and HTTP request?

5. is there anything more than address?

A few persons request clarification about #5. My original intent was to ask an open-ended question to stir your curiosity. Nevertheless, I answered on canvas as such:

For #5, there are many things to note among various layers (that's the purpose of the rest of semester). One important "thing" related to addressing is the port number. What did you make out of it? Instead of just google it, try to see if you can guess/reason the purpose of it.

• Does DNS and HTTP have the same port number?

• Can DNS and HTTP have the same ip address? Can the same machine serve as both DNS server and HTTP server?

• What happens if two browser tabs go to the same web server?

HW chapter 1

From textbook chapter 1 problems.

Solve problems 5, 6, 9, 18, 24, 28, 30. (no need for #9)

HW CH#1 Problem Description

HW (chapter 2) -

R13 and problems 1, 3, 5, 14, 15, 18 (part a, f, g)

HW CH2 Problem Description (problem 14,15 are SMTP, they are not part of the CMPE148 subjects. Will not be tested.)

Midterm prep recommendations:

1. Do the homework, including the exercises (wireshark, http, telnet, nslookup, tracert, etc)

2. Do the review questions in the book

3. Understand what we discussed in the class

4. Exam papers from previous semesters

HW (TCP seq/ack)

Analyze your example.com tcp sequences. Make sure you understand the two pipe full duplex seq/ack interactions.

HW (chapter 3) Part-1

Problems 2, 3, 25, 27, 33

HW CH#3 Part-1 Problem Description

HW (chapter 3) Part-2

Problems 37, 40, 42, 44, 46

HW CH#3 Part-2 Problem Description

HW (chapter 4) -- IP data plane

Problems 1,10,11,16,19

HW CH4 Problem Description

HW DHCP/IP/NAT

1. design an experiment to capture and analyze DHCP protocol (discovery, offer, request, renew.... etc).

2. investigate the ip layer of the above captures.

3. submit your findings about

   • (a) your design of the DHCP experiment method

   • (b) interesting aspects of DHCP protocols

   • (c) interesting aspects of IP

   • (d) if you can figure out the working of NAT, that will be bonus

For (b) and (c), you decide what's interesting to you.

HW (chapter 5) -- IP control plane

Problems 1, 3, 4, 5, 8

HW (chapter 6) Link Layer

This is for your reference in preparation for the final. No need to submit your work.

Problems: 1, 3, 5, 14, 15, 16, 28, 31

HW CH6 Problem Descriptions