Portability of Data

Syllabus requires you to:


Protocols and standards:

Communication standards:

Emergence of standards:

Communications Protocols

The British Computer Society (BCS) defines a communications protocol as “a standard set of rules used to ensure the proper transfer of data between devices”. Protocols specify the format of the data and the signals to start, control and end the transfer of data.


Many protocols have been established by the International Telecommunications Union (ITU) and the International Standards Organisation (ISO).



Open Systems Interconnection (OSI)

Internet Protocols

TCP/IP (transmission control protocol / internet protocol)

Other protocols specify how particular types of data are structured, for example file transfer protocol (FTP) and hypertext transfer protocol (HTTP).


Hypertext transfer protocol (HTTP)

File transfer protocol (FTP)


Simple mail transfer protocol (SMTP)

Post office protocol 3 (POP3)

Point-to-point protocol (PPP)

Serial line Internet protocol (SLIP)