SSH and RDP: Definitions, Comparison & Tips

In today's digital age, connecting remotely to servers and infrastructure is paramount. Two leading protocols dominate this space: RDP (Remote Desktop Protocol) and SSH (Secure Shell). While RDP connections offer graphical interfaces, especially for Windows environments, SSH provides a command-line interface, predominantly for Linux servers.

The debate between SSH and RDP or vice-versa often boils down to specific user needs and security considerations. This article delves deep into these protocols, comparing their security features and providing tips for optimal usage.

Part 1. What are SSH and RDP?

1.1 What is SSH, and How Does It Work?

SSH, which stands for Secure Shell, is a security protocol and is one of the most common ways to securely manage connections to remote servers securely. By leveraging encryption technologies, SSH provides a mechanism to establish a cryptographically secure relationship between two parties, verifying the identity of each and sharing methods for sending and receiving data.

The essence of SSH's security lies in its encryption techniques. SSH employs various data manipulation techniques at different stages of a transaction. These techniques involve symmetric encryption, asymmetric encryption, and hashing.

1. Symmetric Encryption: This type of encryption uses a single key to encrypt messages sent to another party and to decrypt messages received from the same party. Anyone with access to this unique key can encrypt and decrypt messages. SSH uses symmetric encryption to encrypt the entire connection. Contrary to popular belief, the public and private key pair (of asymmetric encryption) generated is used only for authentication, not for encrypting the connection.
2. Asymmetric Encryption: Asymmetric encryption differs from symmetric encryption, requiring two related keys to send data in one direction. One is known as the private key, and the other is the public key. The public key can be shared with anyone, while the private key remains confidential. The public key is associated with the private key, but the private key cannot be derived from the public key.

SSH is used for various purposes, including remote access, file transfers, X11 Forwarding, port forwarding, tunneling, and network management. 

1.2 What is RDP and How Does It Work?

RDP, or Remote Desktop Protocol, is a proprietary protocol developed by Microsoft. It allows users to connect to another computer over a network connection in a graphical interface, making it feel like they are using the remote computer locally.

RDP is primarily used for accessing Windows virtual machines (VMs) and physical Windows servers. It provides a user-friendly Windows Graphical User Interface (GUI) experience, making servers more accessible to a broader audience, including those without a technical background.

However, for remote access, RDP ports often need internet connectivity. For security reasons, it's recommended to shield RDP instances with a virtual private network (VPN) or a form of multi-factor authentication (MFA) since RDP ports can be susceptible to attacks when exposed online.

Part 2. SSH vs. RDP – Which Should You Choose?

Remote access to server infrastructure is a daily necessity for IT and DevOps organizations. When it comes to choosing an authentication protocol, two major contenders often come into play: the Windows® Remote Desktop Protocol (RDP) and the Secure Shell (SSH) protocol. Both have their merits and demerits, and the choice often boils down to specific user needs and scenarios.

RDP Overview

RDP is exclusively designed for accessing Windows virtual machines (VMs) and physical Windows servers. It provides a Windows Graphical User Interface (GUI) experience, making it more user-friendly and accessible even to those without a technical background.

However, because RDP ports often need internet connectivity for remote access, they can be vulnerable to attacks when exposed. For enhanced security, protecting RDP instances with a virtual private network (VPN) or multi-factor authentication (MFA) is advisable.

SSH Overview

On the other hand, SSH is optimized for Linux server access but is versatile enough for any operating system’s server. Unlike RDP, SSH doesn't offer a GUI but provides a command-line interface, typically controlled through bash. This makes SSH more technically demanding for end-users.

The primary security feature of SSH is its client/server authentication model, which uses public/private key pairs instead of traditional credentials. These keys function similarly to a conventional lock and key, with the public key acting as the lock and the private key as the unique access key. SSH's authentication is considered more secure than a standard username and password due to the 2048-bit encryption used by each key.

Comparing RDP vs. SSH

Both RDP and SSH are essential for securely accessing cloud-based servers and are invaluable for remote employees accessing on-prem infrastructure. However, they have distinct differences:

• Security: SSH is inherently more secure than RDP. The key pairs used in SSH are generally harder to compromise than traditional credentials. However, no system is entirely foolproof. Even with SSH keys, organizations must ensure that end users diligently protect their private keys.
• User-friendliness: RDP, with its GUI, requires less technical expertise than SSH. This makes RDP more appealing to organizations with limited technical know-how or smaller IT teams. The GUI-centric nature of RDP makes it accessible even to non-technical employees.

Choosing Between RDP and SSH

The choice between SSH over RDP largely depends on the specific needs and scenarios. SSH might be the preferred choice if the primary concern is security and the users are technically adept. However, if ease of use and accessibility for a broader range of employees are the main criteria, RDP could be more suitable.

Cloud directory services can be leveraged for those looking to secure both RDP and SSH from the cloud. These services can help establish multi-factor authentication on Windows systems and manage SSH key pairs, ensuring enhanced security regardless of the protocol chosen.

Part 3. RPD and SSH Security Vulnerabilities

As the digital landscape evolves, so do the threats that target various protocols and systems. Both SSH and RDP are widely used for remote access, but they come with their own set of vulnerabilities that organizations must be aware of.

SSH Vulnerabilities

SSH (Secure Shell) is a protocol that runs secured network services over insecure networks. It provides cryptographic host authentication, user authentication, strong encryption, solid data integrity protection, and multi-tunneling of data channels. While SSH remote desktop is known for its security features, it's not without vulnerabilities.

• Authentication Vulnerabilities: Although secure, the authentication process in remote desktop SSH can be compromised if the private keys are mishandled or exposed.
• Man-in-the-Middle Attacks: If an attacker can intercept the initial connection request, they can potentially act as a bridge between the client and server, relaying messages between them and potentially gaining unauthorized access.

RDP Vulnerabilities

RDP (Remote Desktop Protocol) is primarily used within Windows OS to access physical or virtual servers. It provides a graphical user interface, making it user-friendly. However, RDP has vulnerabilities:

• Unrestricted Port Access: Most RDP connections use port 3389 by default. If this port is left open, it can be a potential entry point for cybercriminals.
• Brute-force Credential Attacks: Weak or insecure user credentials can be exploited using brute-force attacks. Attackers try various combinations to gain unauthorized access.
• Remote Code Execution Vulnerabilities: RDP has vulnerabilities allowing attackers to execute arbitrary code on a target system. One notable example is the BlueKeep vulnerability (CVE-2019-0708).

Mitigating the Vulnerabilities

To ensure a secure remote connection, organizations must adopt best practices:

• Regularly Update and Patch: Ensure that both SSH and RDP are regularly updated to the latest versions. This helps in fixing any known vulnerabilities.
• Use Strong Authentication Methods: For SSH, use key-based authentication, and for RDP, use multi-factor authentication.
• Limit Access: Restrict access to SSH and RDP only to trusted networks and users.
• Monitor and Audit: Regularly monitor and audit SSH and RDP logs to detect any unauthorized access attempts.

Part 4. Explore a New Option for Secure Remote Access

In the ever-evolving world of remote access, Avica Remote Desktop emerges as a leading third-party remote access software, offering a blend of user-friendliness, robust security, and advanced features tailored to meet diverse needs.

Security at its Core

Avica prioritizes user security above all. It employs end-to-end AES-256 encryption, ensuring that all data transmitted between devices remains confidential and protected from potential threats. Additionally, Avica offers a unique privacy mode, which prevents unauthorized viewing by blacking out the remote device's screen. This feature ensures that your work remains private, even when accessing remotely.

Low Latency with High-Quality Experience

Avica boasts a patented streaming protocol that guarantees a stable connection, even in weak network conditions. This ensures a seamless remote access experience with minimal disruptions. Furthermore, users can enjoy a high-quality visual experience with 4K resolution and 4:4:4 color support.

User-Friendly Interface

Navigating Avica is a breeze, thanks to its simple and intuitive user interface. Whether you're a designer, engineer, gamer, or IT professional, Avica's platform is tailored to enhance your remote access experience. 

Diverse Features for Varied Needs

• Digital Board/Screen: Avica's interface is sensitive and responsive to pressure and tilt, enhancing the user experience.
• Game Controllers: For gaming enthusiasts, Avica supports up to four game controllers connected simultaneously for gaming enthusiasts.
• Drag-and-Drop File Transfer: Transferring files is a breeze with Avica's drag-and-drop functionality.
• Virtual Screen: Users can create multiple virtual screens on the remote device's monitors, enhancing multitasking capabilities.
• Voice Sync: Avica supports the transmission of sound from the local device to the remote device, ensuring a comprehensive remote experience.

You can easily download Avica software by clicking the button provided below. For more detailed information regarding Avica App downloads, please visit the official Avica download page. It is important to note that Avica ensures the safety and virus-free nature of all products available on its official website or app store. Feel confident in downloading Avica from these trusted sources.

Free Download

Conclusion

In the realm of remote access, both RDP and SSH offer distinct advantages. While RDP caters to those seeking a graphical interface, SSH emphasizes secure command-line connections. The choice between them depends on individual needs and security priorities.