Module One Overview

Lessons Learned in Module One

Module One featured an overview of the layered communication models, the OSI and TCP/IP layered models. The models are fundamental in understanding the communication functions of a computing network system, and feature 7 and 4 layers, respectively. In depth learning about these models was obtained from videos from Eli the Computer Guy and Professor Messer. To demonstrate this knowledge, I created tables detailing each model, answered questions from the professor, and created a vocabulary table. This was one of the most useful assignments of the module, and I will cover it more in detail in the learning artifact section below.

The next assignments covered application protocols and DNS, as well as network media. Again, information was learned from Eli the Computer Guy and Professor Messer, and demonstrated by answering a number of questions and creating table. The application protocols segment primarily covered information about the application level of the TCP/IP and OSI models, and the DNS protocols section explored in-depth how a Domain Name System functions. The final section, Network Media, covered the details of the different types of cabling and media that can be used to create a network. This has significant importance in understanding what types of cabling are best for different situations and learning the specifications of each different type of cable.

Learning Artifact

The most useful learning tool in this module for me was watching videos from Eli the Computer Guy and Professor Messer regarding the OSI and TCP/IP models. Understanding the functions at each layer, and the protocols and hardware utilized by each, is fundamental to understanding how networks operate and how to diagnose problems that can occur at the various levels. The videos in particular were very useful because Eli goes into very detailed information about each layer, whereas Professor Messer does an excellent job of giving a broad overview of the models. Part of the deliverable for this assignment was to create tables for each model, details the function, protocols, and hardware utilized at each layer. An example of these tables can be found below.


The OSI Model
Layer Name
Function
Protocols
Hardware
Application End user's access to the network; provides a set of utilities for application programs HTTP, MIME, SMTP, DNS, FTP Web applications, email, file transfer
Presentation Formats the data for presentation to the user; accommodates different interfaces on different computers TLS, AFP, JPEG, GIF Images, embedded items
Session Manages and structures all sessions; does session initiation and termination RPC, SQL, NFS, SSH Logical ports
Transport Establishes, maintains, and terminates logical connections fro the transfer of data TCP, UDP Multiplexing
Network Performs routing; determines where messages should be sent IP Routers
Data Link Manages the physical transmission circuit and transforms it into a circuit that is free of transmission errors; performs error detection and correction and decides when a device can transmit ATM, PPP, STP Switches, bridges, WAPs
Physical Physical connection between computers and/or devices in the network Ethernet, DSL, 802.11 Hubs, repeaters, cabling

The TCP/IP Model
Layer Name
Function
Protocols
Hardware
Application Application software used by the network user; user's access to the network HTTP, MIME, SMTP, DNS, FTP Web applications, email, file transfer
Transport Links the application layer software to the network and establishes end-to-end connections between sender and receiver UDP, TCP Multiplexing
Internet Allows exchange of information between hosts that are not attached to the same physical medium IP Routers
Link Allows two hotsts that are directly connected through a physical connection to exchange information; the medium connecting these devices is used to transfer an electrical or optical signal between two directly connected devices SLIP, PPP, Ethernet, DSL Switches, bridges, hubs, cabling