What is Telnet?
Telnet protocol is user to connect the remote Computer(also called as Host computer) over the TCP/IP network. Using Telnet client software we can establish a connection with the remote server such as (Linux,Unix,Mac).Once you establish a connection your terminal become an virtual Terminal.
Telnet can works on Port no 23.
We have to enter the command in command Prompt as
telnet hostname/IP address Port No(By default 23),which establish connection with the remote server.
Disadvantage using Telnet
The data transferred in between Client and server is in the form of Plane Text.
So there must be a possibility of Intruder (Hacker) can hack the data while data is being transmitted. So Telnet is not secure Protocol.
It can be used in small Offices,Colleges,Labs where there is no primary issue of security.
Most of Big companies strictly prohibit the use of telnet. They use SSH Protocol to connect with the Remote server which is very secure than the Telnet protocol.
Implementation of telnet server in RHEL6/FEDORA/CENTOS
For implementing the telnet server in Fedora/Centos/Rhel6 it is necessary to check the following package must be installed on system.
1.Check whether the packages are installed on system or not
rpm -qa telnet-server
rpm –qa xinetd
2.If the packages are not installed Install using yum or rpm command.
yum –y install telnet* xinetd
3.After installation of packages go to the configuration file of telnet and make change configuration file as follows.
make disabled=no .so Telnet client can connect to the remote server.
4.Restart the xinetd service and also make telnet server can be available at booting time on as follows
service xinted restart
chkconfig telnet on
5.Telnet client can’t directly connected to root account. so add one user and assing password to that user
Logging to telnet server using the telnet client
1.Telnet client is not enabled on windows by default. for enabling it do following steps:
Start->Control Panel->Programs and Features->Turn Windows Feature on or off
->(check the check box) telnet->click on Ok button.
It will turn the telnet feature on.
2.Go to Run -> type CMD.
3.within Command Prompt type the command as follows
telnet ip ( ip address of remote server)
4.It will ask for login user and password for connecting to the remote server, type User name and Password .