PuTTYgen, part of the open-source network networking client PuTTY, is a crucial generating tool to create public and private SSH keys for servers. The native file format of PuTTY is .ppk files. Additionally, the tool is used for SSH connectivity. So users can use PuTTY to connect and securely transfer data from localhost to remote system.
But to use PuTTY, the private keys must be in the native format of the application. So for example, as Amazon Elastic Compute Cloud (EC2), a core part of the cloud-computing platform, generates Privacy-Enhanced Mail (PEM) file format, a user must first convert the file to .ppk file format before connecting to Linux Instance (virtual server on Amazon Web Services) from a Windows machine.
The EC2 allows users to lease virtual systems so that they can run their applications on it.
However if one plans to use PuTTY’s SSH client to connect, then they are first required to convert the .pem file to .ppk using PuTTYgen and then use the PuTTY application to join local and remote hosts.
What Is the .Pem File Format?
Privacy-Enhanced Mail (PEM) file extension is a format that is mainly used to transmit data, certificates, email, and cryptographic keys privately. The PEM file format is a tamperproof and secure way of storing and transferring data.
As a ‘.pem file’ can store multiple types of data; it represents data with the appropriate suffix. While the most common is .pem suffix, others include .key for private keys and .cer or .crt for certificates. The PEM file format encodes it with the binary-to-text encoding scheme – base64 so that it represents binary data in ASCII string.
Even though technological advancements have led to a more secure alternative to PEM containers, it is still leveraged to store public and private certificates, root certificates and many others.
Unlike most file formats that are easy to convert via online conversion tools, a user requires a specific application to convert files that have .pem extensions. PuTTYgen is one such application that quickly converts f .pem files to .ppk.
Convert .Pem to .Ppk using PuTTYgen
The primary requisite is to download and install the PuTTY application. As part of the networking client, PuTTYgen does not have to be downloaded separately. Users must download the latest version of the app and install the entire suite. Once installed, PuTTYgen will be ready to convert .pem files to .ppk format. We will provide detailed steps to convert files on both operating systems – Windows and Unix.
Converting .Pem to .Ppk on Windows
1 Click on Start menu> All Programs > PuTTY > PuTTYgen.
2 The following window will present with options on the crucial user wants to generate. Select the option ‘RSA (Rivest–Shamir–Adleman). RSA is a public-key cryptosystem that is commonly used to transmit data securely. Users with an older version of PuTTY should select the option – ‘SSH-2 RSA.’
3 Next, click on the option ‘Load.’ As PuTTY supports its native file format, it will only show files that have .ppk file extension. Therefore, users have to choose the ‘All Files’ option from the drop-down bar. It will display all key files included the .pem file.
4 Now, select the .pem file that you want to convert. As aforementioned that PuTTYgen is used for SSH connectivity, so it crucial for users to select the specific file that they plan to convert and click ‘Open.’ To confirm, click on ‘OK.’
5 In the resultant window, click on ‘Save private key’ which will convert and save the key file in PuTTY compatible format.
6 PuTTYgen will prompt a warning of saving the key without a passphrase. Hit ‘Yes’ on it.
7 Now, give the name to your file and PuTTYgen will automatically add .ppk file extension.
Note – Passphrases provide extra protection, but it sometimes gets annoying as each time a user copies files they have to enter the passphrase. Although, it entirely depends on the user if they wish or don’t wish to add the extra layer of protection
Once the file is converted to a PuTTY compatible format, users can connect their local machine with remote servers.