Most of a technician’s work, in either a small or a large network, will in some way be involved with network protocols. Network protocols support the applications and services used by employees in a small network. Common network protocols include:
- DNS
- Telnet
- IMAP, SMTP, POP (email)
- DHCP
- HTTP
- FTP
Click the servers in the figure for a brief description of the network services each provides.
These network protocols comprise the fundamental tool set of a network professional. Each of these network protocols defines:
- Processes on either end of a communication session
- Types of messages
- Syntax of the messages
- Meaning of informational fields
- How messages are sent and the expected response
- Interaction with the next lower layer
Many companies have established a policy of using secure versions of these protocols whenever possible. These protocols are HTTPS, SFTP, and SSH.