D1 - Protocols: Application Layers

Application Layers:

HTTP:

Hypertext Transfer Protocol

Port No. 80

Downloads web pages.

HTTPS:
Hypertext Transfer Protocol Secure
Port No. 443
Secures communications

FTP:
File Transfer Protocol
Port No. 21
Simple transmission of files (TCP/IP)

SMTP:
Simple Mail Transfer Protocol
Port No. 25
Email message between servers

Telnet:
Telecoms Network Protocol
Port No. 992
Remote login - Controls from distance

POP3
Post Office Protocol 3
Port No. 110
Allows user to download emails.

SSH:
Secure Shell
Port No. 22
Remote log on, runs scripts and commands.

DNS:
Domain Name System
Port No. 53

IMAP:
Internet Mail Access Protocol
Port No. 993
Receives emails.