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Which Client Software Is Better for Telnet and SSH?

Updated on October 11, 2021
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You could access a server in another place as easily as you wanted while you were sitting right at the keyboard using Telnet and SSH. Various Telnet clients and SSH clients running Telnet and SSH protocol can help access the Telnet server and SSH server to execute configuration and management remotely. Telnet vs SSH: what are the differences? And among multiple Telnet clients and SSH clients, such as PuTTY, SecureCRT, which should you choose? Or how to access Telnet and SSH on computing platforms. This post gives the answers.

Telnet vs SSH: Definition & Difference

Telnet and SSH (Secure Shell) are two network protocols used to connect to remote servers in order to facilitate some sort of communications. They enable network administrators to remotely access and manage a device. So both of them are considered terminal emulators. Still, they possess some different features. Below are their definitions and main differences.


Sr. No. Key Telnet SSH
1 Definition Telnet is the joint abbreviation of Telecommunications and Networks and it is a networking protocol best known for UNIX platform designed specifically for local area networks. On other hand SSH or Secure Shell is a program to log into another computer over a network, to execute commands in a remote machine, and to move files from one machine to another.
2 Operation Telnet uses the port 23 and it was designed specifically for local area networks. SSH on other hand runs on port 22 by default however it can be easily changed.
3 Security As compared to SSH Telnet is less secured. On other hand SSH is a very secure protocol because it shares and sends the information in encrypted form
4 Data format Telnet transfers the data in simple plain text. On other hand SSH uses Encrypted format to send data and also uses a secure channel.
5 Authentication No authentication or privileges are provided for user's authentication. As SSH is more secure so it uses public key encryption for authentication.
6 Preference Due to its less security private networks are recommended for Telnet. On other hand SSH suitable for Public networks.

    Telnet Client Software & SSH Client Software Comparison

    As stated above, both Telnet and SSH allow users to communicate with remote devices. To use Telnet or SSH, you must have a software installed—Telnet client or SSH client running over Telnet or SSH protocol. And on the remote device, a Telnet server or an SSH server must be installed and running. (P.S. Telnet is built in and enabled by default in most windows operating systems). Multiple Telnet clients and SSH clients are available. According to Wikipedia, some of those Telnet clients and SSH clients are listed in the following table.


    Telnet Client SSH Client
    PuTTY, free, open-source, for Windows, Linux and Unix. AbsoluteTelnet for Windows, also supports SSH. RUMBA (Terminal Emulator) NCSA Telnet TeraTerm SecureCRT from VanDyke Software ZOC Terminal
    PuTTY, free, open-source, for Windows, Linux and Unix. AbsoluteTelnet for Windows, also supports SSH. OpenSSH SecureCRT from VanDyke Software SSH Secure Shell Client SunSSH Xshell

    Telnet Client Software: Free or Commercial

    What is the best Telnet client? Opinions vary. But most people will choose between TeraTerm and SecureCRT, Telnet clients can also be divided into free and commercial one. TeraTerm is an open source, free software implemented, terminal emulator program. It’s one of the most popular Windows terminal programs. It’s simple to use. In addition to standard terminal emulator functionality, Teraterm has macro language which allows to automate login to most frequently used servers. Unfortunately few people understand this very important and productivity enhancing (especially for sysadmins) feature of Teraterm. SecureCRT is a commercial SSH and Telnet client and terminal emulator by VanDyke software. SecureCRT client for Windows, Mac and Linux provides rock-solid terminal emulation for computing professionals, raising productivity with advanced session management and a host of ways to save time and streamline repetitive tasks. SecureCRT provides secure remote access, file transfer, and data tunneling for everyone in your organization. Whether you are replacing Telnet or Terminal, or need a more capable secure remote access tool, SecureCRT is an application you can live in all day long. With the solid security of SSH, extensive session management, and advanced scripting, SecureCRT will help raise your productivity to the nth degree.

    Figure 1: Use SecureCRT to establish remote connection

    SSH Client Software: Free or Commercial

    With various SSH clients, which is the best SSH client for Windows? Like Telnet clients, there are also free and commercial SSH clients. Here takes PuTTY and Tectia SSH as examples. For the free and open source SSH clients, PuTTY is probably the most popular SSH client for Windows. It has good terminal emulation, good configurability, and good support for different cryptographic algorithms. It also supports public key authentication and Kerberos single-sign-on. A major shortcoming of PuTTY is that it does not have integrated file transfers in the client itself. Instead, file transfers have to be done via the command line. This is too complicated for most users. Moreover, PuTTY does not come with an SSH server. It can be used with Linux OpenSSH.

    Figure 2: The most popular SSH client—PuTTY

    For commercial SSH clients, Tectia SSH is commercially supported SSH client for enterprise, with 24x4 support. Tectia SSH secures remote system administration, provides encrypted file transfers, and enables secure system automation. On Windows, Tectia SSH supports both file transfers and command line access. Command line access is very useful for remote administration of Windows servers in data centers, across firewalls, and for scripting administrative actions. Tectia SSH client is used by many enterprises for system administration and for running legacy text-based applications. Kind reminder: which SSH/Telnet to use depends on your requirements. The one fitting your network would be the best. If you can’t decide which secure shell or telnet client to use, start with PuTTY.

    Network Switch Telnet/SSH Remotely Configuration Guide

    A network switch, as a Telnet server or an SSH server, can connect to multiple Telnet or SSH clients. Telnet clients are typically LAN users, while SSH clients can be both LAN users and WAN users. How to access a network switch remotely and configure it over Telnet and SSH?


    How to Configure a Network Switch Remotely Over Telnet Client Software?

    A Telnet session lets you access a network switch remotely using the default port 23. Entering Telnet followed by the switch IP address can establish a Telnet session connection.

    switch# telnet 10.17.37.157

    If the switch is active and the Telnet service is enabled on it, a display like the following will appear.

    Trying 10.17.37.157... Connected to 10.17.37.157. Escape character is '^]'. Network OS (sw0) switch login:

    You can log in normally, once you have established the Telnet connection.

    How to Configure a Network Switch Remotely Over SSH Client Software?

    In order to establish SSH connection successfully, please pay attention to the following points:

    Create the connection between SSH client and SSH server. The version of SSH client and SSH server should be the same. The key matched. SSH function in server should be enabled.

    You can use the SSH command to connect a remote server and open a shell session there. The simplest form assumes that your username on your local machine is the same as that on the remote server. If this is true, you can connect using:

    ssh remote_host

    If your username is different on the remote server, you need to pass the remote user’s name like this:

    ssh username@remote_host

    Your first time connecting to a new host, you will see a message that looks like this:

    The authenticity of host '111.111.11.111 (111.111.11.111)' can't be established.

    ECDSA key fingerprint is fd:fd:d4:f9:77:fe:73:84:e1:55:00:ad:d6:6d:22:fe.

    Are you sure you want to continue connecting (yes/no)? yes

    Type “yes” to accept the authenticity of the remote host. If you are using password authentication, you will be prompted for the password for the remote account here. If you are using SSH keys, you will be prompted for your private key’s passphrase if one is set, otherwise you will be logged in automatically.

    When configuring SSH on a network switch, one of the steps will be to create a public/private SSH key which your SSH client will use to authenticate the switch when your connect. Each switch will have its own SSH key. It is recommended you save and install this key to whatever client you’re using to prevent man-in-the-middle attacks. In general, you can configure a remote network switch over SSH by these three steps: enable SSH, display SSH configuration to ensure the keyfile can be used, open SSH client in PC and log in switch. Take FS.COM network switches as examples, you can also access the network switch remotely and configure it over Telnet using various Telnet software clients but with the same display, or over SSH using various SSH software clients with the same display.

    Summary

    Telnet sends all packets of data through IP networks as clear text, which includes the username and password. In most cases, it can be a potential security risk that is very easy to abuse. When using Telnet for monitoring switches or routers, you must have in mind the security risk behind Telnet connection to the device. SSH is more secure by using encryption of data packets that are crossing the network. No matter Telnet or SSH, they actually do the same thing—access the command line of an operating system from wherever you are over the network.

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