TCP/IP Model & How it Relates to Browsing the Internet AnonymouslyBY: HELEN LIN

Contents

What is the TCP/IP model?

History

Layers of TCP/IP

Internet Layer

Way to browse the internet anonymously

What are the drawbacks?

TCP/IP Model

TCP/IP stands for Transmission Control Protocol and Internet Protocol.

Transmission Control Protocol and Internet Protocol (TCP/IP) is a collection of protocols designed to facilitate how data and communication are handled over a large network.

History

It was developed in 1969 by the U.S. Department of Defense (DoD) Defense Advanced Research Projects Agency (DARPA).

TCP/IP was born from a resource-sharing experiment called Advanced Research Projects Agency Network (ARPANET) which later evolved into what we now know as the internet.

TCP/IP is maintained by the Internet Engineering Task Force (IETF) which operates under the Internet Society – an international non-profit organization, is dedicated to providing “relevant technical documents that influences the way people design, use, and manage the internet.”

Layers of TCP/IP Model

The TCP/IP model can be broken down into four major layers:

Application layer

Transport layer

Internet layer

Network interface layer / Network access layer

Layers of TCP/IP Model

Application layer - defines how programs run by the host interacts with transport layer services to access the network

Transport layer - provides the communication session management between host computers.

This layer defines the level of service and status of the connection used when transporting data.

Internet layer - responsible for packaging data into IP datagrams (packets).

IP datagrams contain the source and destination address as information used to forward the datagram across the network.

The internet layer is comprised of many protocols such as: IP (Internet Protocol)

Network interface layer - responsible for detailing how data is physically sent through the network, i.e. it details how bits are electrically signaled by devices that interface with the network e.g. coaxial cables.

TCP/IP Model

IP – Internet Protocol

Internet Protocol (IP), a internet layer protocol, defines the format of datagrams (or packets), and the addressing scheme.

Every computer on the network has an IP address that identifies it.

IP is an connectionless protocol, i.e. there is no connection between the source and destination.

Packets are treated as independent data and is reorganized correctly due to TCP.

Public IP Address

Public IP address – used by internet servers, network routers, or any computer connected directly to the Internet via a modem.

Can be accessed over the internet like a postal address.

How to figure out your public IP address?

Google search “IP”

In some emails, you can find the IP address of the email sender.

What can someone do with your public IP address?

Get your location.

Using geolocation to get the router or the ISP location.

It’s possible to obtain a person’s exact location (however, it may be difficult).

Attack your computer/network.

DDOS.

Malicious users may scan your network for open ports or simply break into your router and act as a computer on the network, etc.

IP Geolocation Websites

These IP Geolocation websites typically show the location of the ISP (internet service provider) providing the connection.

http://geomaplookup.net/

http://www.infosniper.net/

http://www.myiptest.com/

IP Geolocation: http://www.myiptest.com/

Ways to Mask Your IP Address

Proxy Servers

VPN (virtual private network) software/services

Proxy Servers

A proxy server functions as an intermediary between your computer and the Internet.

Traffic from your browser is re-routed and made to appear to come from the proxy server's IP address.

Ex. Tor Browser - Internet traffic is routed through Tor’s network.

Disadvantage:

The proxy server owner can may view information saved on their cache such as passwords, usernames, browsing history.

VPN (Virtual Private Network)

VPN mask your IP address and also encrypt all the traffic from your computer to the desired destination by using encryption protocols and secure tunneling techniques.

VPNs also secure your data when using public Wi-Fi networks.

Ex. Foxyproxy – offers both VPN and proxy.

Disadvantage:

The VPN provider may have security vulnerabilities.

References (1 of 3)

http://www.studytonight.com/computer-networks/comparison-osi-tcp-model

http://networking.layer-x.com/pic/fig004.jpg

https://i-technet.sec.s-msft.com/dynimg/IC197700.gif

http://www.ietf.org

https://msdn.microsoft.com/en-us/library/aa767734(v=vs.85).aspx

http://www.yaldex.com/tcp_ip/FILES/15fig02.gif

http://searchnetworking.techtarget.com/definition/Telnet

http://d9clients.com/images/ftp_guide/ftp_diagram.jpg

http://searchenterprisewan.techtarget.com/definition/File-Transfer-Protocol

https://www.techopedia.com/definition/1881/trivial-file-transfer-protocol-tftp

http://www.wtcs.org/snmp4tpc/images/snmp.gif

http://www.networkmanagementsoftware.com/snmp-tutorial

http://1.bp.blogspot.com/-gTRV25VTdb8/T55rvji6cEI/AAAAAAAACXM/9clbBo-y0nY/s1600/dnslookups.png

http://searchnetworking.techtarget.com/definition/domain-name-system

http://www.vicomsoft.com/images/learning-center/email-and-email-servers/emailtwelve.gif

References (2 of 3)

http://whatismyipaddress.com/smtp

https://upload.wikimedia.org/wikipedia/commons/7/75/Internet1.jpg

http://www.omnisecu.com/images/cisco-certified-network-associate-ccna/rip-hop-count.jpg

http://searchnetworking.techtarget.com/definition/Routing-Information-Protocol

http://i.stack.imgur.com/uATzu.jpg

https://www.techopedia.com/definition/9760/transport-layer

https://upload.wikimedia.org/wikibooks/en/0/0f/Fig2_UDPwork.jpg

https://www.techopedia.com/definition/13460/user-datagram-protocol-udp

http://www.itgeared.com/images/content/1094-1.png

http://searchnetworking.techtarget.com/definition/ICMP

http://searchunifiedcommunications.techtarget.com/definition/Internet-Protocol

http://protocols.netlab.uky.edu/~edulab/images/int.gif

http://searchnetworking.techtarget.com/definition/Address-Resolution-Protocol-ARP

http://www.lgosys.com/products/FrameSeerHelp/Frame.gif

http://searchnetworking.techtarget.com/definition/Ethernet

References (3 of 3)

https://docs.getfoxyproxy.org/index.php/Difference_between_Proxy_and_VPN

https://getfoxyproxy.org/vpn/proxy-or-vpn.html

http://www.myiptest.com/