When is ssh used

Ensuring proper policies, processes, and audits also for SSH usage is critical for proper identity and access management. We provide services and tools for implementing SSH key management. Once a connection has been established between the SSH client and server, the data that is transmitted is encrypted according to the parameters negotiated in the setup. During the negotiation the client and server agree on the symmetric encryption algorithm to be used and generate the encryption key that will be used.

The traffic between the communicating parties is protected with industry standard strong encryption algorithms such as AES Advanced Encryption Standard , and the SSH protocol also includes a mechanism that ensures the integrity of the transmitted data by using standard hash algorithms such as SHA-2 Standard Hashing Algorithm.

It is now an internet standard that is described in the following documents:. It runs over SSH, and is currently documented in. The public key file format is not a formal standard it is an informational document , but many implementations support this format. Together with our customers, our mission is to secure their digital business on on-premises, cloud, and hybrid ecosystems cost-efficiently, at scale, and without disruptions to their operations or business continuity.

In even modestly complex environments, manual SSH Key rotation is infeasible. For instance, you could identify accounts set up to use SSH keys, you could manually scan through authorized keys file in the hidden. SSH user folder, but this falls short of helping you identify who has the private key matching any of the public keys in the file. Organizations who recognize the risks posed by SSH Key sprawl risk and take a proactive cybersecurity posture, typically use a dedicated SSH key management or automated privileged password management PPM solution to generate unique key pairs for each system, and perform frequent rotation.

Automated solutions dramatically simplify the process of creating and rotating SSH keys, eliminating SSH key sprawl, and ensuring SSH keys enable productivity without compromising security. To tighten security controls around SSH Keys, you should also apply the following six best practices:. This is also an appropriate juncture to determine who is using various keys and how.

This will provide an effective SSH audit trail and more direct oversight. This limits the potential fallout from misuse of SSH keys. Stay Attentive to SSH Key Rotation: Implement diligent SSH Key rotation — force users to generate keys on a regular basis and disallow use of the same passphrases across multiple accounts or iterations.

These actions help protect the organization from password reuse attacks. In organizations with a large SSH key estate, this can only be feasibly performed via an automated solution. This practice creates dangerous backdoors for malware and hackers to exploit. Embedded keys that use simple or default passphrases may be vulnerable to password-guessing and other attacks. Therefore, an important piece of SSH security is to uncover and eliminate embedded SSH keys, and bring them under centralized management.

Audit All Privileged Session Activity: Any privileged session started via SSH Key authentication or other means should be recorded and audited to meet both cybersecurity and regulatory needs. Privileged session management activities can entail capturing keystrokes and screens allowing for live view and playback. Ideally, you also layer on the ability to control pause or terminate privileged sessions in real-time to maintain strong oversight and a short leash over privileged activity.

This method is quick, it is not resource-intensive, and SSH uses it for each session. Data is asymmetrically encrypted when machines use two different but mathematically related keys, public and private, to perform the encryption. The client machine that participated in setting up the encryption can decrypt the information using the private key. SSH uses temporal asymmetric keys to exchange symmetric keys, such as during the user authentication process. SSH uses hashing to validate if the data packets come from the source they appear to come from.

A hashing algorithm uses a data packet to create a unique hash string. The machine sending the packet always sends the packet together with the hash value. The receiving machine knows the algorithm used to create the hash and can apply it to the data. The purpose is to see if the calculated hash value will be the same. This article aimed to give you a better sense of the mechanisms behind SSH. Understanding how SSH works and why it is useful should help you decide if you want to use it in your personal or work environment.

December 17, What is SSH? What is SSH Used for? Introduction Data transmission between devices on a network needs to be regulated for devices to communicate properly. Was this article helpful? Marko Aleksic. His innate curiosity regarding all things IT, combined with over a decade long background in writing, teaching and working in IT-related fields, led him to technical writing, where he has an opportunity to employ his skills and make technology less daunting to everyone.

Next you should read. Networking Security Web Servers. Fix SSH connection refused by troubleshooting some of the common causes for this problem.