Telnet and FTP are the TCP/IP, application layer, connection-oriented protocols which establishes a connection to the server from the remote host to remotely log in to a system or transfer a file. These protocols can be used in a collaborated way, to transparently log in to the FTP server and then can be used to transfer files.
The common difference between Telnet and FTP is that Telnet permits a client user to login to remote server to access its resources while FTP is used to transfer a file to the remote machine.
Content: Telnet Vs FTP
Comparison Chart
| Basis for comparison | Telnet | FTP |
|---|---|---|
| Basic | It allows a user to log in to the remote server. | It allows a user to transfer a file to the remote machine. |
| Functions on Port number | 23 | 21 and 20 |
| Security | May have some security concerns. | More secure than Telnet. |
| Remote login | Is required to access the system resources. | Not necessarily needed. |
Definition of Telnet
Telnet is a standard TCP/IP protocol for providing virtual terminal services standardized by ISO. In this protocol, the client-server first sets up a connection link with the remote server and then keystrokes from the user’s keyboard are transferred directly to the remote computer, which looks like the keystrokes were passed from the keyboard connected to the machine. The result is also carried back to the user from the remote machine. The process is considered to be transparent to the users because it seems like the user is directly attached to the remote machine.
The remote machine is identified by Telnet client software through defining either of its IP address or domain name. The process for accessing a remote machine can be complicated because the different operating system could be running on the different machine and also every machine and its operating system accept a combination of unique characters as tokens. So here we are handling heterogeneous system where we need a mechanism to find the computer type and its specific terminal emulator which we want to access remotely.
Here comes Network Virtual Terminal (NVT) a universal interface defined by Telnet. With the help of the NVT, the client Telnet software transforms characters (data or commands) coming from the local terminal into NVT form and transmit them to the network. Then the server Telnet translates NVT form of data and commands into the form that can be accepted by the remote computer.
There are three standard services provided by Telnet. Firstly, it provides an interface to the remote system defined by Network Virtual Terminal (NVT) as mentioned above. The client program is devised to use the standard interface and it need not to understand the internal details of all possible remote systems. Secondly, Telnet provides a mechanism which enables the client and the server to settle options and a set of standard options. Lastly, both ends of the connection are equally treated by Telnet.
Definition of FTP
File Transfer Protocol (FTP) is primarily used for transferring the files from local machine to remote machine. FTP client establishes the connection with the help of the TCP. The FTP server allows multiple client to access the server concurrently. The transfer of a file to the remote machine may encounter some issues such as file name conventions, directory structure and representation of text and data in two different system can be distinct which would make transferring of file difficult.
FTP sets up two connections between the hosts which makes it more efficient. The first connection is used for transferring the data and other for controlling the information (commands and responses). In the control connection, only one line of command or response is transferred at a time. FTP uses port 21 for control connection and port 20 for data connection. In the entire FTP session, the control connection remains activated while data connection opens for transferring files and then closed when the file is completely transferred.
Key Differences Between Telnet and FTP
- Telnet enables a client user to access the resources of a server remotely whereas FTP is used for copying a file from one to another machine.
- The Telnet protocol uses port number 23 for the connection. On the contrary, FTP uses port 21 and 20 for control and data connections respectively.
- Telnet doesn’t employ security measures hence it is insecure. As against, FTP uses encryption methods which implement security.
- In Telnet the user needs to log in first in the remote machine then any operations can be performed. Conversely, in FTP the user need not log in to the remote machine.
Conclusion
Telnet is used for logging in the remote machine in order to access its resources while FTP is a file transfer protocol used to transfer a file from one host to another in a network or internet.
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