Archive for March, 2013


Net 1 Lab 5

Ian Reese
Lab 5: Sniffing with Wireshark

Objectives: Track packets as they are sent using wireshark to learn about how they are transferred.

Notes and Observations:

Browsing a webpage on a server outside of campus:

1 browsingweb

File transfer on FTP server:

2 ftp

Testing connection with a ping:

5 download

Acquiring a network address with DHCP:

4 dhcp

Downloading a font file from dafont.com:

3 ping

Questions:

1. What is the purpose of sequence numbers?

– So they can be reassembled in the way they were transmitted.

2. What is the purpose of source and destination addresses?

– So the devices that are used to send the packets know who information is from and where it goes.

3. What is the purpose of DNS?

– So that users can type in a hostname and it can be translated into the meaningful IP address that the hardware uses to address information.

4. What is DHCP?

– Dynamic Host Configuration Protocol is a protocol used to configure devices connected to a network so they can communicate on an IP network.

5. What is the relationship between the OSI model of networking and what you saw in this lab activity?

6. What evidence of layered network design did you discover when examining captured data? How does the wireshark data demonstrate encapsulation?

7. What are the implications of having a tool like wireshark freely available? For network administration? For security?


Conclusions:

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Net 1 Lab 4

Ian Reese
Lab 4: IP Networking
Partner: Jon

Objectives: Our objective was to create a simple class “C” Network and the configure a router so our class “C” could communicate with a class “B” that another group were doing. Unfortunately we didn’t have the equipment to configure the router so we had to watch our instructor just demonstrate how you would configure a router.

Notes and Observations: The part that we were able to do was fairly simple, but we did run into one bump. That being that you need to completely close out of Local Area Connection Status window in order for manual IP configurations to come into effect. The amount of things that went wrong for the second part was quite notable. The upgraded computers ended up not having the connector that was needed as well as needing to download software to finally get a communication going between the input on the computer and the router. I think after getting hands on experience with configuring a router I will get a better understanding and find it quite easy, but for now I just have a rough understanding.


Conclusions: We managed to ping one another in the command window successfully. Technology can be a real pain.

This week in Networking we went over our test and talked more about encapsulation. Going to be completely honest with this and say that I didn’t learn anything in this week that I can remember.

Net 1 Blog 4

This week in Networking we only had one day of class and took an Exam that day. I did decent, but felt I could’ve done better if I gave some of the questions a second thought. The one that I got wrong that bothers me the most is question 24.    where it asks what electricity is the flow of. For some reason my brain that day immediately went to neutrons. If I had gone over the three aspects of an atom, protons, neutrons, and electrons, in my head, I would have instantly realized my mistake in thinking it was neutrons. So what I learned from going over this test is that for the next ones I should not quickly fly through some of the questions, but think about the logistics for a few seconds.

Net 1 Lab 3

Ian Reese
Lab 3: OSI Model
3/3/2013

1. If we already had the TCP/IP model, why was the more complicated OSI model created?

2. What does the abbreviation OSI stand for? Who originated it? When?

Open Systems Interconnection. Charles Bachman provided the concept in the 1970’s and it was fully created and incorporated by the International Organization of Standardization.

3.

Layer # Layer Name Mnemonic Keywords & Description of Function
7 Application Animals
6 Presentation Poisonous
5 Session Super
4 Transport Touch
3 Network Not
2 Data-Link Do
1 Physical Please

4. Determine the highest layer of operation for the following network devices:

Layer 1: hub, repeater, patch panel

Layer 2: bridge, NIC, wireless access point, cable media, switch

Layer 3: router, switch

5. What is another name for a physical address? How many bits do they require? When two machines attempt to transmit simultaneously on the same media segment, both messages become garbled and unintelligible. What is this condition normally called?

MAC Address. 48 bits. It is called a data collision.

6. What is your IP address? What is your MAC address?

129.130.175.17 and 40-61-86-06-54-83 respectively

7. ARP ends in a “P” so what does that often signify?

That the P stands for Protocol.

What does ARP stand for & what does it do?

At the command prompt type arp –d *. This command clears your arp table. Type arp –a to verify there are currently no entries in the arp table. Now ping your neighbor’s computer by typing ping and their IP address. Did you get a reply? If not, be sure the windows firewall is turned off. Why is ping useful? Retype arp –a and record any changes. What is your neighbor’s physical address? Have your neighbor verify their physical address. Is it what is displayed in your arp table? Add two more entries to the arp table by pinging two other machines in the lab. What address is added to the arp table when you ping http://www.sal.ksu.edu? Why?

8. If a packet comes in from another network, only a layer 3 (IP) address is known. But direct machine to machine communication only occurs at layer 2. What method is used to translate a known layer 3 address into an unknown layer 2 address?

Encapsulation

9. Network Layer Layer 3 devices allow the interconnectivity of different local area networks through gateways. What are layer 3 gateway devices called? They use logical, or software encoded addresses. Many types of software addresses have been developed and used. What is the de-facto standard for logical addresses used today? How many bits do they require?

10.