Resource Request
Requirements
Building upon the back of Section 1, this portion of the final will focus on transferring a BasicStamp (.bs2) file from the Manufacturing Branch Office in Maine to the Headquarters Office in Arizona and then back again. The final requirements outline the following requirements for this portion of the final:
- In addition to transferring this file back and forth, 20 concepts that allow the data to move from Maine to Arizona and back again will be discussed.
- Do not cut and paste from another source.
- Use your own words and understanding of the concepts to explain the process. If you reference or use a quote to provide clarity to a concept, you must reference your source. This will be prose not fill in the blank or in list format. This section will consist of the following:
- Minimum of 20 concepts along the “path” of the resource request. Each layer of the TCP/IP model (Chapters 2, 3, 4/5, 6) will have a minimum of five concepts explained (5 x 4 = 20). Each concept is worth two points.
- Each step will consist of the following:
- Concept
- Concept Definition
- Applicable Port and Protocol
- Applicable data unit (Data, Segment, Datagram, Frame)
- What this concept provides the user
- For each concept you use you will label your network diagram with where that concept takes place
Example
Bob would like to access a webpage at www.example.com. His computer does not currently have an IP address so his computer creates a DHCP message request. The DHCP server is a network management protocol that dynamically assigns IP address to network devices. It uses two ports 67 for the server and 68 for the client. This message is contained within a UDP segment which will be encapsulated within an IP datagram. When DHCP provides Bob’s computer with an IP address the computer will be able to communicate networked resources.
Following a most troublesome and disturbing situation, an investigation took place regarding the events which occurred when Party A attempted to book a public speaking event at the Four Seasons Hotel (www.FourSeasons.com). This investigation was requested by the most top-ranking members of this committee because the speaking event was mistakenly booked at the Four Seasons Total Landscaping Corp (www.FourSeasonsTotalLandscapingCorp.com). This action resulted in political embarrassment to the cause of this organization and in the words of the most recent memorandum, will result in the termination of whomever is responsible.
To begin, it was discovered that Party A utilized an Office Network laptop, with Internet Protocol (IP) address of 192.168.20.16 (NL-2), to book this event. An IP address is not a port; rather, it is a unique number provided for each end system that allows users to send and receive packets of data (Kurose, 2017, p. 53). This laptop was connected to the Internet, as well as a Wide Area Network (WAN), across the Local Area Network (LAN)(DL-4). This is because the laptop had previously received an IP address on the Office Network Virtual Local Area Network (VLAN)(DL-5) 20. This happened when the Dynamic Host Control Protocol (DHCP) server received and replied to a request message. This message request was transmitted across the network on an 802.11 Wireless Access Point (WAP) (DL-3). This encapsulated what is called User Datagram Protocol (UDP)(TL-1) segment. UDP protocol utilizes port 53 to provide a connectionless service to its applications, which allowed Party A to transmit across the Internet (Kurose, 2017, p. 79). Regardless, this UDP segment had been broadcast to the network within an IP version4 (IPv4) (NL-1) datagram. Upon receipt of this IP datagram, the wireless Network Interface Card (NIC) (DL-2) re-encapsulated the message into a link layer frame for transmission into the 802.11 Ethernet (DL-4) network. Thus, enabling the laptop to be connected to the internet.
It was also discovered that Party A accessed the content required to book the public speaking event using Internet Explorer (IE), which is a software program called a Web Browser (AL-1). The Web is a client-server relationship which allows users to obtain documents on demand. A Web Browser communicates on a server’s port 80 or 443 and is the Hypertext Transfer Protocol (HTTP) client-side application designed to access Web content published on Web Servers (Kurose, 2017, p. 130). A Web Server implements the service side of the HTTP and stores objects which may be accessed by a Uniform Resource Locator (URL)(Kurose, 2017, p. 130). Using IE, Party A navigated to www.Yahoo.com. Next, Party A’s laptop conducted a Domain Name System (DNS) query to locate the IP address for www.Yahoo.com web client server (DL-1). The laptop then created a TCP (TL-2) connection with Yahoo!’s web server through a three-way handshake (TL-3). This established a TCP socket connection from Yahoo!’s web server at port 80 (AL-2) to the laptop on port 9100 (AL-2). However, Yahoo! utilizes Secure Socket Layer (SSL) protection on their website; therefore, Party A was redirected to Yahoo!’s web service located at port 443 in order to use Hypertext Transfer Protocol Secure (HTTPS)(AL-3). After connecting to Yahoo! on the right port, the web server utilized Transport Layer Security (TLS)(TL-4) to enable encrypted communication to transfer web traffic. Next, the company router (NL-5) performed a Network Address Translation (NAT)(NL-3) to replace the laptop IP address with a public IP address. Finally, Party A typed into Yahoo!’s search bar for “Four Seasons near me” and clicked on the first search result connecting him to www.FourSeasonsTotalLandscapingCorp.com.
Once Party A was on the www.FourSeasonsTotalLandscapingCorp.com website, they clicked on the email address Sales@FourSeasonsTotalLandscapingCorp.com, which automatically opened Microsoft (MS) Outlook. Using MS outlook, Party A composed an email requesting to know the fee for booking a speaking event in an “open air” environment. This email was sent utilizing Simple Mail Transport Protocol (SMTP)(AL-4) on this organization’s email server. After Party A had left for the day, he established an encrypted connection with an IP Security Protocol (IPSec)(NL-4) datagram from his Home Network to the laptop left in the Office Network. Doing so allowed a Virtual Private Network (VPN)(TL-5) connection to the Office Network laptop, where Party A responded to the email to book the speaking event. Finally, Party A opened FileZilla, a Secure Shell (SSH)(AL-5) software application, and he connected to the company file directory server on port 22 to upload invitations for the media into the shared media folder.
| Layer | Diagram Key | Term |
| Application | AL-1 | Web Browser |
| Application | AL-2 | Port Number |
| Application | AL-3 | HTTP/HTTPS |
| Application | AL-4 | SMTP |
| Application | AL-5 | SSH |
| Transport | TL-1 | UDP |
| Transport | TL-2 | TCP |
| Transport | TL-3 | 3-way handshake |
| Transport | TL-4 | TLS |
| Transport | TL-5 | VPN |
| Network | NL-1 | IPv4 |
| Network | NL-2 | IP Address |
| Network | NL-3 | NAT |
| Network | NL-4 | IPsec |
| Network | NL-5 | Router |
| Data Link | DL-1 | Web Server |
| Data Link | DL-2 | NIC |
| Data Link | DL-3 | 802.11 Wireless AP |
| Data Link | DL-4 | Ethernet/LAN |
| Data Link | DL-5 | VLAN |
References
Kurose, J. F., & Ross, K. W. (2017). Computer networking: A top-down approach (Vol. 7). Boston, MA: Pearson.
