Part of the CCNA certification requires you to know the TCP/IP Model.
TCP/IP stands for Transport Control Protocol/Internet Protocol
The layers of the TCP/IP model are:
The Application Layer
The purpose of the Application layer is basically to operate the user initiated protocols such as FTP and SMTP. As compared to the OSI model, the Application layer of the TCP/IP model incorporates the Application and Presentation layer from the OSI model. The data then gets encapsulated and handed over to the Transport layer.
The Transport Layer
The purpose of the Transport layer is to guarantee delivery of all segments without error. It is a reliable protocol with error control, fragmentation and flow control. The obvious protocol used in this layer is TCP which is connection-oriented.
It ensures that:
Data is arrived in the correct order (The Transport layer will re-send the missing data)
Arrives at destination without error (It will re-send that data if there are errors)
The Internet Layer
This layer deals with routing data packets from the source to it’s destination. It has the core purpose of using ip addressing, forwarding and routing between devices.
Protocols utilized here are IP and ICMP.
The Network Access Layer
Here we deal with the physical connection to network hardware. These are the 1′s and 0′s of networking. Defined in this layer is the access to the physical network and exchange data from one network/device to another.
Related posts:
- Layers of the OSI Model
- CCNA Notes – IP Addressing and Routing
- CCNA Notes on the Basics of WANs
- WAN Link Protocols
