Acronyms and Lab Assignment

Acronyms-(Hourglass)

1)      HTTP: Hyper Text Transfer Protocol is part of the application layer in the OSI model. HTTP formats and transmits messages. It also lets us connect to World Wide Web.

Sources: http://www.webopedia.com/TERM/H/HTTP.html

2)      SMTP: Simple Mail Transfer Protocol is part of the application layer in the OSI model. SMTP sends emails between servers.  It is commonly used to send messages between email clients and mail servers.

Sources: http://www.webopedia.com/TERM/S/SMTP.html

3)      RTP: Real-Time Transport Protocol is part of the session layer in the OSI model. RTP transmits real time data such as audio and video.  

Sources: http://www.webopedia.com/TERM/R/RTP.html

4)      DNS: Domain Name System is part of the application layer in the OSI model. DNS purpose is to translate domain names into IP addresses. Having a DNS is beneficial because it’s easier to remember DNS rather than memorizing IP’s.

Sources: http://www.webopedia.com/TERM/D/DNS.html

5)      TCP: Transmission Control Protocol is part of the transport layer in the OSI model. TCP allows a connection between two hosts, so that data can be transferred.  

Sources: http://www.webopedia.com/TERM/T/TCP.html

6)      UDP: User Datagram Protocol is part of the transport layer in the OSI model. UDP broadcasts messages through the network along with providing a few error recovery services.

Sources: http://www.webopedia.com/TERM/U/User_Datagram_Protocol.html

7)      IP: Internet Protocol is part of the network layer in the OSI model. IP delivers packets from one host to its destination. It relays datagrams through the network.

Sources: http://www.webopedia.com/TERM/I/IP.html

8)      ICMP: Internet Control Message Protocol is part of the network layer in the OSI model. ICMP’s purpose is to send error message indications to network devices. It is also an addition to the Internet Protocol.

Sources: http://www.webopedia.com/TERM/I/ICMP.html

9)      DSL: Digital Subscriber Line is part of the physical layer in the OSI model. DSL allows data transfer through wires of local telephone network.

Sources: http://en.wikipedia.org/wiki/Dsl

10)   SONET: Synchronous Optical Network is part of the physical layer in the OSI model. SONET’s role is to connect fiber-optic transmission systems.

Sources: http://www.webopedia.com/TERM/S/SONET.html

11)   802.11 is part of the physical layer in the OSI model. 802.11 supports data transfer in a wireless local area network. It’s an over-the-air interface which allows the client and host to connect.

Sources: http://www.webopedia.com/TERM/8/802_11.html

12)   ETHERNET is part of the physical layer in the OSI model. It supports data transfer in a local area network.  It uses a bus or star topology.

Sources: http://www.webopedia.com/TERM/E/Ethernet.html

 LAB Assignemnt

CS 461-Lab 1-Questions 1-5

1) Sketch a small network, for example your home network. Label all links, routers and hosts. The type of each link (wired or wireless, bluetooth, wifi, 3G or 4G) should be evident from the picture (e.g., through solid or dotted line etc). You may use pen/pencil and paper to complete this assignment because computer based drawing software are a waste of time and energy. Submit a hard copy of your diagram in the next class.

I will submit Hardcopy in class

2) Use traceroute to trace the route to any two IP addresses on the campus network. Explain each line in the output. Submit your answer in blogs.

I chose not to install linux, instead I did the tracert using windows 7.

The first IP is my routers IP 192.168.1.1

The domain www.york.cuny.edu was converted into Tracing route to sun3.york.cuny.edu [198.61.16.7] over a maximum of 30 hops:

From 15 to 30 # of hops requested a time out.

*Request timed out.

# of Hops	Hop 1 time ms	Hop 2 time ms	Hop 3 time ms	Domain Name	IP Address
1	1   ms	1   ms	1   ms	Wireless_Broadband_Router.home	192.168.1.1
2	9   ms	6   ms	11 ms	L100.NYCMNY-VFTTP-125.verizon-gni.net	72.89.93.1	NY, USA
3	11 ms	12 ms	9   ms	G1-5-5-0.NYCMNY-LCR-22.verizon-gni.net	130.81.189.102	USA
4	7   ms	10 ms	8   ms	ae4-0.NY5030-BB-RTR2.verizon-gni.net	130.81.163.232	USA
5	13 ms	33 ms	10 ms	0.xe-3-1-0.BR3.NYC4.ALTER.NET	152.63.26.117	USA
6	27 ms	28 ms	27 ms	te-7-3-0.edge2.NewYork2.level3.net	4.68.111.137	USA
7	33 ms	33 ms	34 ms	vlan51.ebr1.NewYork2.Level3.net	4.69.138.222	USA
8	34 ms	33 ms	39 ms	ae-47-47.ebr1.NewYork1.Level3.net	4.69.201.45	USA
9	47 ms	42 ms	31 ms	ae-1-8.bar2.Boston1.Level3.net	4.69.140.97	USA
10	32 ms	32 ms	31 ms	CWIE-LLC.bar2.Boston1.Level3.net	4.53.54.6	USA
11	14 ms	14 ms	14 ms	xe-1-0-0.nycmnyzrj42.lightower.net	72.22.160.152	NY, USA
12	14 ms	18 ms	15 ms	64.72.64.110.available.lightower.net	64.72.64.110	NY, USA
13	17 ms	13 ms	14 ms	ae3-nycmnyaaj41.lightower.net	72.22.160.172	NY, USA
14	20 ms	13 ms	16 ms	162.220.40.254.lightower.net	162.220.40.254	USA
15	*	*	*	Request timed out.
16	*	*	*	Request timed out.
17	*	*	*	Request timed out.
18	*	*	*	Request timed out.
19	*	*	*	Request timed out.
20	*	*	*	Request timed out.
21	*	*	*	Request timed out.
22	*	*	*	Request timed out.
23	*	*	*	Request timed out.
24	*	*	*	Request timed out.
25	*	*	*	Request timed out.
26	*	*	*	Request timed out.
27	*	*	*	Request timed out.
28	*	*	*	Request timed out.
29	*	*	*	Request timed out.
30	*	*	*	Request timed out.

Tracing route to home.cunyfirst.cuny.edu [128.228.157.141] over a maximum of 30 hops:

# 6 hop- requested time out and 15 to 30 # of hops requested a time out.

# of Hops	Hop 1 time ms	Hop 2 time ms	Hop 3 time ms	Domain Name	IP Address
1	1   ms	1   ms	1   ms	Wireless_Broadband_Router.home	192.168.1.1
2	11  ms	9   ms	13 ms	L100.NYCMNY-VFTTP-125.verizon-gni.net	72.89.93.1
3	11  ms	12 ms	9   ms	G1-5-5-0.NYCMNY-LCR-22.verizon-gni.net	130.81.189.102
4	11  ms	9  ms	9   ms	ae4-0.NY5030-BB-RTR1.verizon-gni.net	130.81.163.224
5	10 ms	10 ms	20 ms	0.xe-10-1-0.BR1.NYC1.ALTER.NET	152.63.18.225
6	*	*	*	Request timed out.
7	49 ms	49 ms	51 ms	ms  vlan51.ebr1.NewYork2.Level3.net	4.69.138.222
8	51 ms	54 ms	46 ms	ae-48-48.ebr1.NewYork1.Level3.net	4.69.201.49
9	55 ms	54 ms	51 ms	ae-1-8.bar2.Boston1.Level3.net	4.69.140.97
10	94 ms	51 ms	52 ms	CWIE-LLC.bar2.Boston1.Level3.net	4.53.54.6
11	39 ms	39 ms	39 ms	xe-1-0-0.nycmnyzrj42.lightower.net	72.22.160.152
12	40 ms	44 ms	46 ms	64.72.64.110.available.lightower.net	64.72.64.110
13	37 ms	39 ms	47 ms	ae3-nycmnyaaj41.lightower.net	72.22.160.172
14	43 ms	45 ms	44 ms	162.220.40.254.lightower.net	162.220.40.254
15	*	*	*	Request timed out.
16	*	*	*	Request timed out.
17	*	*	*	Request timed out.
18	*	*	*	Request timed out.
19	*	*	*	Request timed out.
20	*	*	*	Request timed out.
21	*	*	*	Request timed out.
22	*	*	*	Request timed out.
23	*	*	*	Request timed out.
24	*	*	*	Request timed out.
25	*	*	*	Request timed out.
26	*	*	*	Request timed out.
27	*	*	*	Request timed out.
28	*	*	*	Request timed out.
29	*	*	*	Request timed out.
30	*	*	*	Request timed out.

3) Use traceroute to any dotcom website hosted in your home country. This might not work from campus because traceroute is blocked by the firewall so try at home. Then copy all IP addresses in the trace and do a web search "where is <IP address>". Note and write or draw the geographic route your query took. Submit your answer in blogs.

I had a difficult time finding websites that are hosted in my home country, so I searched one from neighboring country: www.net4.in. I used whereismyip.net to search for location.

# of Hops	IP Address	Location
1	192.168.1.1	New York, USA
2	72.89.93.1	New York, USA
3	130.81.107.174	New York, USA
4	130.81.151.228	New York, USA
5	152.63.23.181	New York, USA
6	209.58.26.93	Quebec, Canada
7	63.243.128.38	Quebec, Canada
8	80.231.200.13	Europe
9	80.231.217.1	Europe
10	80.231.217.18	Europe
11	180.87.38.2	Maharashtra, India
12	180.87.39.26	Maharashtra, India
13	Request timed out
14	Request timed out
15	Request timed out
16	121.241.156.74	India
17	61.8.147.230	India
18	202.71.131.8	Uttar Pradesh, India

   

4) Connection oriented service provides 6 service primitives. In programmers terms, these are functions that can be used to achieve some tasks). The socket API exposes these functions to application developers for writing apps that communicate across a network. You will use these APIs soon to write your own networked apps. For now, research the following to get started:

Find the function definition (return type, input parameters, names and the header files needed to use these functions) of all the primitives that are available in the C programming language. Write these down clearly in the following format:

Open Socket:

int socket (int namespace, int style, int protocol)

header file: sys/socket.h

Creates a socket and specifies communication style (SOCK_STREAM, SOCK_DGRAM or

SOCK_RAW), namespace (PF_LOCAL or PF_INET) and protocol designates the specific

protocol (default is zero which usually works best).

The return value from socket is the file descriptor for the new socket, or -1 in case of error

Submit your answer in blogs.

#include<sys/socket.h>

Int socket