How to Learn Network Protocolsby Chris Loza
Learning network protocols can be daunting because of the complexity of getting computers to communicate with each other. With a little organizational skill, it's relatively easy to learn common networking protocols. It's important to consider the umbrella category under which all these protocols fall into. The OSI (Open Systems Interconnect) model houses all protocols under each layer, primarily: Application, Presentation, Session, Transport, Network, Data Link and Physical layers. These layers have common protocols used in networking.
Learning Network Protocols
Memorize the seven OSI layers using the commonly-used mnemonic "All People Seem To Need Data Processing" -- for Application, Presentation, Session, Transport, Network, Data link and Physical layers.
Remember that the Application layer is for applications that interface with users. Functions included here are emails, file transfers, web-browsing and remote access. Common email protocols are SMTP (Simple Mail Transfer Protocol) and POP3 (Post Office Protocol version 3). Web-browsing has HTTP (Hypertext Transfer Protocol). File transfer has FTP (file transfer protocol).
Remember that the Presentation layer is involved in the presentation of data. This includes audio, video and other visual presentations. Protocols include the common JPEG for pictures, MP3 for music, AVI for videos.
Remember that the Session layer is responsible for establishing a session or connection between computers and networks. Common protocols include SQL (structured query language) and RPC (remote procedure call).
Remember that the Transport layer is involved in transmitting or transferring data from one device to another. Common protocols are TCP (Transport Control Protocol) and UDP (User Datagram Protocol).
Remember that the Network layer is responsible for tracking and routing where data should be transmitted. To be able to route data correctly, computers need "addresses," which the Internet Protocol (IP) is responsible for. Similar to courier and cargo services, the network layer also has the RIP (Routing Information Protocol), EGP (External Gateway Protocol) and IGMP (Internet Group Management Protocol). These are the trucks, planes, and trains responsible for routing data.
Remember that the Data link layer is responsible for linking or connecting data between the other protocols. It provides error-free mechanism to ensure that the link is maintained. Common protocol is PPP (Point-to-Point Protocol) and SLIP (Serial Line Internet Protocol).
Remember that the Physical layer are the physical connections between networks and computers. These are the wires, cables, switches, amplifiers and other physical devices that link computers. There is no protocol under the Physical layer.