As we deep dive into TCP/IP and OSI protocols, looking at each one’s architecture. TCP/IP consists of four to five layers application, transport, network, data link, and physical. OSI (International Organization for Standardization) consists of seven layers application, presentation, session, transport, network, data link, and physical.
Both Protocols use application for their first layers. The application layer supports applications and sometimes support services such as encryption and compression. Which user applications like browser and word processing applications are not found within this layer they use protocols that function within the application layer. Application Protocols used for TCP/IP and OSI include HTTP (Hypertext Transfer Protocol) which allows browsers and servers to send and receive web pages. SMTP (Simple Mail Transfer Protocol) enables users to send and receive emails. FTP (File Transfer Protocol) moves files from one computer to another. SSH (Secure Shell) allows remote computers to securely log in to other computer systems. SNMP (simple Network Management Protocol) manages the numerous elements in a computer network to be managed at a single point.
Looking at the second layer of TCP/IP and OSI which they differ. TCP/IP second layer is the Transport Layer. Which uses TCP (Transmission Control Protocol) this allows for an error free end to end connection. TCP protocol is not the only protocol found in the Transport Layer. You can also find UDP (User Datagram Protocol) this is not commonly found within this layer and usually used when steaming data like music or videos. OSI uses the presentation layer for its second layer. We do not find this layer within TCP/IP. Which it performs functions for presenting data properly to the sender or receiver.
The Third layer of TCP/IP and OSI differ also. TCP/IP has the Network layer thirdly. The Network layer also known as Internet layer or IP layer is used to transfer data within, and between networks. IP (Internet Protocol) software which prepares packets of data for transmission between the networks. OSI third layer consists of the session layer and is not found within the layering of TCP/IP protocol. The session layer consists of transferring large amounts back and forth between two systems. It uses a point after each small section of transmission to ensure proper data transmission.
Now we are at the fourth layer of TCP/IP and OSI protocols. TCP/IP uses Data Link at this layer. Data Link layer which gets data from user’s workstations and passes it to the router connected to the Internet. Commonly the LAN gets the data from workstation to Internet. The Data Link Layer prepares data for transmission to a router sitting between the LAN and internet. OSI’s fourth layer is the second layer of TCP/IP, Transport Layer. Which verifies the data that arrived at the destination is the same sent from the original station.
Diving into the fifth layer of TCP/IP and OSI we see they also differ. With TCP/IP we find the Physical Layer which is the final layer of its architecture. This is where the data transmission occurs. This can be through physical wiring, or radio signal. OSI uses the same layer TCP/IP uses at its third layer. Network layer also known as Internet layer or IP layer is used to transfer data within, and between networks. IP (Internet Protocol) software which prepares packets of data for transmission between the networks.
OSI architecture only contains two more layers which are included in the architecture of TCP/IP. The sixth layer of OSI is the Data Link layer it prepares data for transmission to a router sitting between the LAN and internet. OSI’s fourth layer is the second layer of TCP/IP, Transport Layer. Which verifies the data that arrived at the destination is the same sent from the original station. The seventh layer is the Physical layer which is the final layer of OSI architecture. The physical layer where the data transmission occurs. This can be through physical wiring, or radio signal.
After deep diving into both TCP/IP and OSI protocols we can see that OSI architecture is bigger and more in depth then TCP/IP. Understanding their architecture really brings why and what purpose would you want to use ether. My opinion is that you would use OSI in a more secured networked area and TCP/IP within a expansion and smaller less secure networked area.
References
West, J. (2022). Data Communication and Computer Networks (9th ed.). Cengage Learning US. https://ecpi.vitalsource.com/books/9780357504413
