Computer Science: Protocols, Layers & Translators

Computer Science: Protocols, Layers & Translators

1. Protocols

   • TCP/IP - Transmission Control Protocol/Internet Protocol - enables communication over the internet.
   • HTTP / HTTPS - Hypertext Transfer Protocol - communication between webserver and client. HTTPS (secure) includes secure encryption.
   • FTP - File Transfer Protocol - governs the transmission of files across a network and the internet.
   • UDP - User Datagram Protocol - similar to TCP, but it is often faster, allowing for gaming or video calls over the internet.
   • Emails
     • Sending
       • SMTP - Simple Mail Transfer Protocol
     • Recieving
       • IMAP - Internet Message Access Protocol

2. Translators

   • Compiler
   • Interpreter

3. Network Layering

   • Application (1)
     • Applications such as web browsers and email programs operate at this layer.
   • Transport (2)
     • Breaks down the message into packets. Each is given a packet number and the total number of packets. Sets up the communication between hosts.
   • Network (3)
     • Adds the sender’s and recipient’s IP addresses to the packet, packages the data to make it ready for transmission. Also routes the packets across the network.
   • Data Link (4)
     • Network interface card/controller (NIC) and operating system drivers are at this layer.