What to Look for in a Top SFTP Server: Critical Features

Whether it’s sensitive financial data, personal information, or classified documents, organizations must ensure that their files are transferred securely to protect against unauthorized access, data breaches, and cyber threats. Failure to prioritize secure file transfers can lead to severe consequences, including financial losses, reputational damage, and legal repercussions.

Organizations by and large rely on Secure File Transfer Protocol (SFTP) for their secure file transfer needs. SFTP servers play a crucial role in facilitating the secure exchange of files between clients and servers. SFTP provides robust encryption, authentication, access control, and auditing capabilities, ensuring that files remain confidential and tamper-proof during transit. In this article, we will explore what to look for when evaluating SFTP servers to ensure you invest in the best and most secure solution relative to your business needs.

Secure File Transfer Protocol (SFTP): A Quick Refresher

SFTP is a network protocol that enables the secure exchange of files over a network. It is built on top of the Secure Shell (SSH) protocol, adding an additional layer of security to file transfers. SFTP provides a secure and reliable method for transferring files between a client and a server, ensuring that data remains protected from unauthorized access or tampering.

SFTP establishes a secure connection between a client and a server through SSH. The client sends commands to the server to perform file transfer operations, such as uploading, downloading, and deleting files. All files transferred between the client and the server are encrypted, ensuring content confidentiality. SFTP uses a combination of symmetric and asymmetric encryption algorithms to secure the content during transit.

How Does SFTP Compare With FTP and FTPS?

SFTP offers several advantages over traditional file transfer protocols like FTP (File Transfer Protocol) and FTPS (FTP over SSL/TLS). SFTP is more secure and reliable than FTP and FTPS protocols. While FTP sends data in plaintext, making it vulnerable to interception, SFTP encrypts data during transfer, ensuring confidentiality. Additionally, FTPS uses SSL/TLS certificates for security, but can be complex to configure. On the other hand, SFTP only requires SSH access, simplifying setup and administration. For enhanced security and ease of use, many businesses opt for SFTP servers, which offer top-level protection for sensitive data transfers.

Benefits of Using SFTP Over Other Protocols

SFTP combines the FTP and SSH protocols’ best features, making it an ideal choice for secure file transfers. SFTP offers the following benefits:

Security Considerations for SFTP Servers

When selecting an SFTP server for secure file transfers, it is crucial to consider various security considerations to ensure that the SFTP servers offer robust security measures to protect sensitive data during file transfers. These considerations include:

Secure Server Configuration to Avert Potential Security Breaches

When choosing an SFTP server for secure file transfers, one of the most critical considerations is the server’s configuration. It is essential to ensure that the server is configured securely to minimize the risk of unauthorized access and potential security breaches. This includes implementing measures such as disabling unused services and ports, applying regular software updates and patches, and configuring firewalls and intrusion detection systems to monitor and control network traffic.

Secure Protocols and Cipher Suites for Advanced Encryption

Another crucial aspect to consider when evaluating SFTP servers is the support for secure protocols and cipher suites like FIPS 140-2. It is essential to select a server that offers strong encryption algorithms, ensuring that data transmitted between the client and server remains confidential and secure. Servers supporting modern encryption standards such as Advanced Encryption Standard (AES Encryption) and strong key exchange algorithms like Diffie-Hellman are a must-have to ensure secure file transfers.

Strong Password Policies to Protect SFTP Server Access

Secure password policies play a vital role in protecting SFTP servers from unauthorized access attempts. It is recommended to choose a server that enforces strong password requirements, such as minimum length, complexity, and regular password expiration. Additionally, supporting multi-factor authentication, such as combining passwords with tokens or biometrics, adds an extra layer of security to the authentication process, making it harder for potential attackers to compromise the server.

Secure Data Storage to Protect Files at Rest

To ensure the security of sensitive data, it is imperative to select an SFTP server that offers secure data storage capabilities. This includes encryption of files at rest, where data is encrypted and decrypted transparently whenever it is stored or retrieved from disk. By employing strong encryption algorithms, even in the event of physical theft or unauthorized access to server storage, the data remains protected and inaccessible to unauthorized parties.

Encryption Safeguards Against Unauthorized Access

The encryption of files at rest ensures that data stored on the server is protected, even if the storage media is compromised. It is crucial to choose an SFTP server that supports robust encryption algorithms, such as AES, to encrypt the files and safeguard them from unauthorized access.

Protection Against Data Breaches

SFTP servers should also provide additional security measures to protect against potential data breaches. This includes features like access controls, allowing system administrators to define granular permissions to limit user access to specific files or directories. Furthermore, implementing audit trails and logging mechanisms enables monitoring and tracking of user activities, aiding in the detection and investigation of potential security incidents.

Secure Data Transmission Between the Client and Server

Securing data transmission is another essential consideration when selecting an SFTP server. It is crucial to choose a server that utilizes Secure Sockets Layer/Transport Layer Security (SSL/TLS) protocols for secure communication between the client and server. SSL/TLS encrypts the data during transit, preventing eavesdropping and interception. Servers that support the latest versions of SSL/TLS and adhere to recommended security practices, such as disabling vulnerable cipher suites and implementing perfect forward secrecy, offer enhanced protection against potential attacks.

SSL/TLS for Transmitting Over Insecure Networks

SSL/TLS provides a secure channel for data transmission over insecure networks, protecting the confidentiality and integrity of the information being transferred. It is essential to select an SFTP server that supports the latest versions of SSL/TLS protocols, as older versions may have known vulnerabilities that could be exploited by attackers. Additionally, configuring the server to utilize strong encryption algorithms and key exchange mechanisms ensures robust security for data in transit.

Avoiding Data Loss During Transfers

Ensuring data integrity and minimizing the risk of data loss during file transfers is another critical security consideration. Look for SFTP servers that provide reliable mechanisms for resuming interrupted transfers, preventing data corruption or loss due to network failures or unexpected interruptions. Support for data compression during transfers can also enhance efficiency and security by reducing the transmission time and bandwidth usage.

What Else to Look for in an SFTP Server

An organization shouldn’t choose an SFTP server in haste. Organizations rely on SFTP to transfer sensitive information like invoices, customer records, account statements, and more. Should this information be intercepted due to a poorly configured SFTP server, it can lead to a data breach, compliance violation, penalties and fines, litigation, revenue loss, brand erosion, and other serious consequences. As a result, organizations should choose their SFTP server wisely. When choosing an SFTP server for secure file transfers, it is essential to consider the following factors:

1. Advanced Encryption Standards Ensure Content Protection

The strength of encryption algorithms used by an SFTP server is crucial for ensuring the security of file transfers. Look for servers that support industry-standard encryption algorithms like Advanced Encryption Standard (AES) with key lengths of at least 128 bits. AES 128 encryption ensures that your data remains protected even against sophisticated attacks.

Supported Encryption Protocols: All Protocols Are Not Created Equal

In addition to encryption algorithms, consider the supported encryption protocols. Look for servers that support SSH version 2, as it offers improved security features compared to version 1. The SFTP server should also support the latest versions of SSL/TLS protocols for transport layer security.

2. Key Management for Secure Storage and Handling of Encryption Keys

Proper key management is vital for maintaining the security of your file transfers. Ensure that the SFTP server securely stores encryption keys and handles them in a way that minimizes the risk of unauthorized access. Consider servers that offer features like key encryption and tamper-proof key storage. Look for servers that provide options for key rotation and expiration, allowing you to enforce strict security policies and prevent the misuse of encryption keys.

3. Secure Authentication Mechanisms Protect Content From Unauthorized Access

A reliable SFTP server should support various secure authentication methods to ensure the integrity of user credentials. Look for servers that offer strong password authentication, allowing users to set complex passwords that meet industry best practices. Additionally, support for public key authentication provides an extra layer of security by requiring users to possess a private key that corresponds to their public key stored on the server. Certificates can also be used for authentication, providing a higher level of assurance in verifying user identities.

Multi-factor Authentication: The More Options, the Merrier

For additional security, consider SFTP servers that offer multi-factor authentication options. Multi-factor authentication requires users to provide multiple pieces of evidence to prove their identity, such as a password and a verification code sent to their mobile device. This adds an extra layer of protection against unauthorized access and strengthens the overall security of your file transfers.

4. Access Control and Permissions

Access controls and permissions are crucial for SFTP servers and content protection to ensure that only authorized individuals or systems have the ability to access, modify, or transfer data. They help prevent unauthorized access, protect sensitive information, maintain data integrity, and mitigate the risk of data breaches and unauthorized data transfers.

Granular Control Over User Access Rights Define and Enforce “Need to Know”

To ensure that only authorized users have access to specific files and directories, choose an SFTP server that provides granular control over user access rights. Look for servers that allow administrators to define specific permissions for individual users or groups. This ensures that each user has the necessary privileges to perform their tasks while preventing unauthorized access to sensitive data.

Options for Directory-level Permissions Limit Access to Sensitive Content Among Authorized Users

In addition to user-level permissions, consider servers that offer directory-level permissions. This allows you to specify access rights for specific directories, granting or denying users the ability to read, write, or delete files within those directories. Directory-level permissions provide an added layer of security by restricting access to sensitive information based on user roles or departmental requirements.

5. Firewall and Network Security Ensure Secure and Seamless File Transfers

An SFTP server should support firewall-friendly connections to ensure seamless file transfers even when network security measures are in place. Look for servers that can establish connections over common firewall-friendly ports, such as port 22 for SSH connections. This allows your organization to maintain a secure network environment while still facilitating secure file transfers.

Use of Secure Protocols (SSH, HTTPS) Protect File Transfers From Interception

Ensure that the SFTP server utilizes secure protocols for communication. Secure Shell (SSH) provides a secure channel for data transmission between the client and the server, protecting your files from interception or tampering. Additionally, support for HTTP over SSL/TLS (HTTPS) ensures that file transfers occur securely over the internet, providing an extra layer of protection against potential threats.

6. Compliance and Certifications

Compliance and certification capabilities are important for SFTP servers, as they ensure adherence to industry standards, regulations, and best practices. They provide enhanced security measures, protect sensitive data, mitigate risks, and build trust with customers by demonstrating a commitment to data protection and regulatory compliance. Look for SFTP servers that comply with industry standards and are certified.

Compliance With Industry Standards Is Often a Requirement

For organizations that handle sensitive data, compliance with industry standards is essential. Look for SFTP servers that comply with regulations such as the General Data Protection Regulation (GDPR), the Cybersecurity Maturity Model Certification (CMMC), the Payment Card Industry Data Security Standard (PCI DSS) or the Health Insurance Portability and Accountability Act (HIPAA). Compliance ensures that your file transfers adhere to specific data security and privacy requirements and safeguards against potential legal and financial consequences.

Availability of Certifications for Added Validation

Certifications provide an additional level of assurance about the security and reliability of an SFTP server. Look for servers that have achieved certifications such as the International Organization for Standardization (ISO) 27001 or Service Organization Control 2 (SOC 2). These certifications demonstrate that the server has undergone rigorous assessments and meets the highest standards of security and data protection.

Kiteworks SFTP Functionality With the Versatility of MFT

The Kiteworks Private Content Network provides organizations with a secure and efficient solution for file transfers. The Kiteworks SFTP server features robust security measures, compliance capabilities, and centralized governance. It is designed to protect sensitive content shared through bulk or automated file transfers, ensuring compliance with data privacy regulations worldwide.

The Kiteworks SFTP server is designed with security and compliance in mind. It utilizes AES-256 encryption for data at rest and TLS 1.3 for data in transit. With a hardened virtual appliance, granular access controls, and multi-factor authentication, organizations can achieve compliance with data privacy regulations such as PCI DSS, HIPAA, and GDPR. Comprehensive audit logs enable organizations to detect attacks sooner and maintain a chain of evidence for forensic purposes like eDiscovery.

The Kiteworks SFTP server also offers several secure deployment options, including on-premises, private cloud, hybrid cloud, and FedRAMP virtual private cloud, allowing file transfers and storage to occur on a dedicated instance. This ensures there are no shared resources, reducing the risk of cross-cloud breaches or attacks. Additionally, Kiteworks is FedRAMP Authorized for Moderate Level CUI, making it suitable for use by U.S. government agencies and defense contractors requiring FedRAMP compliance.

Scalability and cost consolidation are also important features (and benefits) of the Kiteworks SFTP server. Organizations can centralize their SFTP servers in a single Kiteworks system, meeting their throughput, availability, and compliance requirements globally. Centralized governance, logging, and administration save administrative time and costs.

The Kiteworks SFTP client offers a compliant and secure solution for connecting to remote SFTP servers. It includes security measures such as security hardening and integration with security stacks. The client is designed for ease of use, with the remote SFTP server appearing as web folders accessed in the same way as web file sharing. Automation capabilities allow for seamless content transfer into and out of SFTP servers, enabling scalability and efficiency.

To learn more about Kiteworks’ SFTP, schedule a custom demo of Kiteworks today.

Additional Resources

• Blog Post SFTP Security – Is It Truly Secure?
• Blog Post Best Secure Managed File Transfer Solutions for Enterprise
• Blog Post How to Find the Best Managed File Transfer Software
• Blog PostWhat Is Managed File Transfer & Why Does It Beat FTP?
• Blog PostHow to Find the Best Managed File Transfer Software