The Complete Guide to FTP, FTPS, SFTP, and SCP

In the digital age, data transfer is integral to operations for businesses of all sizes. While Extract, Transform, and Load (ETL) processes have become fundamental for moving raw data to destinations like data warehouses, the protocols you use to transfer these files can impact the efficiency and security of the entire operation. Dive into our comprehensive guide, as we shed light on the most popular file transfer protocols and their relevance in today's tech landscape.

Here are the 5 key takeaways from the article: 

• FTP is foundational but unencrypted.
• FTPS adds SSL/TLS encryption to FTP.
• SFTP operates securely via SSH.
• SCP offers speed using SSH but has limited features.
• Modern policies like GDPR and HIPAA favor secure transfers, elevating SFTP as the top recommendation.

In this guide, we look into the most-used transfer protocols for moving files from servers to clients via computer networks, enabling ETL to transform data from these files into readable formats for big data analytics. Here's a comparison of FTP, FTPS, SFTP, SCP, and other transfer protocols.

What is FTP?

FTP (File Transfer Protocol) has been the foundational method for transferring files since the 1970s. FTP is a simple way to move files between computers via TCP/IP — the framework that connects network devices online. Here's how FTP usually works:

1. Upload files to the FTP server.
2. Relay these files through TCP/IP to the FTP host.
3. The recipient accesses and downloads the files.

FTP handles three data representations (8-binary data, ASCII 7-Bit, and EBCDIC 8-Bit) and moves files via one of three transmission modes (block, stream, and compressed.) 

FTP Pros:

• Quick and straightforward, with a proven track record spanning four decades.
• Capability to handle multiple directory transfers concurrently.

FTP Cons:

• Lacks encryption, which poses potential security threats.
• Utilizes dual data channels, elevating the risk of unauthorized data interception.

With evolving data governance policies like GDPR and HIPAA, relying on FTP, especially for sensitive data transfers, has become a risk many modern enterprises are unwilling to take.

What is FTPS?

FTPS (File Transfer Protocol Secure, sometimes called FTP/SSL) emerged in the 1990s as a fortified version of FTP. It incorporates an SSL/TLS layer below FTP to encrypt its data channels, enhancing security during transfers.

FTPS Pros

• Lots of internet infrastructure has built-in support for SSL, making it easy to transfer files via FTPS.
• Strong authentication.
• X.509 certificate features.

FTPS Cons

• It can interfere with firewalls, so some users might struggle with it at first. 

Recommended reading: FTPS ETL to Your Warehouse

What is SFTP?

SFTP (Secure File Transfer Protocol), introduced in the late 1990s, offers an encrypted alternative to FTP, operating via SSH. This protocol ensures file security during transfers, making it a robust choice against data breaches.

Similar to SSL, SFTP uses commands to execute the data connection when you transfer files. The recipient of your files connects to the SSH server and authenticates the server with cryptographic keys (SSH keys) or a username/password combo. 

Recommended reading: SFTP ETL to Your Warehouse

SFTP Pros

• Data file encryption.
• Command execution.
• IPV6 HTTP support. 
• TMUX support.
• Username/password authentication.
• Public key authentication.
• One channel for file transfers.
• Excellent choice for various types of flat files, delimited files, plain text files, CSV files, common flat files, files with comma-separated values, and files with a simple structure. 

SFTP Cons

• There are few cons. SFTP is a much safer alternative to FTP, especially for ETL. 

What is SCP?

Leveraging the SSH protocol, SCP (Secure Copy Protocol) transfers files via encrypted IP-based data tunnels, ensuring both speed and security. It does this by moving files between local hosts and remote hosts (or two remote hosts).

SCP Pros

• Like SFTP, SCP uses the SSH protocol for authentication, making it a safer FTP alternative. 
• It's (sometimes) faster than SFTP for file transfers, particularly on high-latency networks. 

SCP Cons

• It lacks file management capabilities.
• It offers little support for resume file transfers.
• It's built for file transfers only. Unlike SFTP, you can't create directories or directory listings or delete files. Depending on the specific data type, it's far more limited in scope.

Other File Transfer Protocols

• TFTP (Trivial File Transfer Protocol) works on the User Datagram Transport Protocol (UDP) for file transfers. It dates back to the early 80s, and few companies use it anymore.
• MFT (Managed File Transfer) has administrative controls that support protocols like SFTP and FTPS. Used in the banking industry, MFT provides additional encryption during financial file transfers. 

Should You Use FTP, FTPS, SFTP, SCP, or Another Protocol?

With cyber threats looming larger than ever, and with the increased focus on data governance and compliance, FTP might not be your best choice. While SCP is a good FTP alternative and sometimes faster than SFTP on high-latency networks, it's limited to file transfers. So you can't delete files, create directories, or execute other functions. 

So that leaves SFTP vs. FTPS. While FTPS is effective and comes with encryption benefits, it's essentially an extension to FTP and still uses two connections. SFTP is an entirely different protocol with one connection, which reduces the risk of hackers stealing your data. As of 2023, SFTP is the safest file transfer protocol for data warehousing projects, with FTPS in second place.

With that, SFTP emerges as the frontrunner, providing both efficiency and security. FTPS, while secure, still operates on the legacy dual connection system, presenting potential vulnerabilities.

How Integrate.io Can Help

Integrate.io provides full support for SFTP and lets you integrate FTPS with some analytics platforms for data analysis, making it the template for ETL workflows. Send and receive files to and from flat file databases, relational databases, data warehouses, database management systems, data lakes, and business intelligence tools without worrying about field names, delimiters, or other data markup issues. 

Integrate.io requires no code or data engineering, making file transfers and data formatting a piece of cake. Whether you want to use SFTP, FTPS, or another transfer protocol, reach out to Integrate.io to learn about our 14-day free trial options.