#7unit 1introduction to e commerce

Internet protocols

The communication rules that run the internet.

Learning Objectives

  • Define what an Internet protocol is.
  • Describe the four-layer TCP/IP architecture.
  • Identify the main Application Layer protocols (HTTP, SMTP, FTP, POP3, IMAP, Telnet, SSL/TLS).
  • Explain the role of each protocol in supporting e-commerce.

Explanation

In simple terms

Internet protocols are rules for how data is transferred across the Internet. TCP/IP is the core; it has four layers, with the Application Layer holding protocols like HTTP (web pages), SMTP/POP3/IMAP (email), FTP (file transfer), Telnet (remote login), and SSL/TLS (secure communication).

A protocol is a set of rules and standards for data transfer. Transmission Control Protocol/Internet Protocol (TCP/IP) has become the core communications protocol for the Internet. TCP establishes connections among sending and receiving computers and makes sure packets arrive in sequence; IP provides the Internet's addressing scheme and is responsible for the actual delivery of packets.

TCP/IP is divided into four layers: the Network Interface Layer (places packets on and receives them from the network medium), the Internet Layer (addresses, packages, and routes messages), the Transport Layer (provides communication with other protocols in the suite by acknowledging and sequencing packets), and the Application Layer (includes a variety of protocols used to provide user services or exchange data).

The Application Layer contains the protocols most visible to e-commerce users. HyperText Transfer Protocol (HTTP) is the Internet protocol used to transfer web pages; HTTP/2 is an updated version with performance and security benefits. Simple Mail Transfer Protocol (SMTP) sends e-mail to a server; Post Office Protocol 3 (POP3) and Internet Message Access Protocol (IMAP) retrieve mail. File Transfer Protocol (FTP) transfers files between server and client. Telnet allows remote login on another computer.

Secure Sockets Layer (SSL)/Transport Layer Security (TLS) operate between the Transport and Application Layers and secure communications between client and server. SSL/TLS helps secure e-commerce communications and payments through techniques such as message encryption and digital signatures. Other Application Layer elements include the Border Gateway Protocol (BGP), which enables the exchange of routing information among autonomous systems on the Internet.

Key Points & Important Terms

Key Points

  • •A protocol is a set of rules and standards for data transfer.
  • •TCP/IP is the core communications protocol for the Internet.
  • •TCP/IP has four layers: Network Interface, Internet, Transport, Application.
  • •Application Layer protocols: HTTP, SMTP, POP3, IMAP, FTP, Telnet, SSL/TLS.
  • •HTTP transfers web pages; SMTP/POP3/IMAP handle email.
  • •SSL/TLS secures client-server communications, including payments.

Important Terms

Protocol
A set of rules and standards for data transfer.
TCP/IP
The core communications protocol for the Internet, divided into four layers.
HTTP
HyperText Transfer Protocol — the Internet protocol used to transfer web pages.
SMTP
Simple Mail Transfer Protocol — used to send e-mail to a server.
FTP
File Transfer Protocol — permits users to transfer files between server and client.
SSL/TLS
Secure Sockets Layer / Transport Layer Security — protocols that secure client-server communications.