Are You Still Using FTP for CAD File Transfer?

This post will explore the pros and cons of using email, FTP, cloud-based file sharing and cloud-based PDM based on my experience with each.

Description: You’re only as strong as your weakest link.

That saying is true for any group endeavor, whether it’s a team sport, product development, world domination, or something simpler like sharing data.

In this post I’ll explore the pros and cons of using email, FTP, cloud-based file sharing and cloud-based PDM based on my experience with GrabCAD Workbench.

Let’s look at a product development scenario.  A designer has finished the preliminary design of a brand new widget.  He is in a small design shop, so he keeps the files on his personal computer. 

He wants a rapid prototype of the design made so he emails the file to a service bureau.  As the bureau is working up a quote for the prototype, the designer notices a few things and makes some tweaks.  The file size is too big now, so he uploads it to his company’s FTP site and emails a notification to the bureau.  But, because the project is still in development and no files have been released, the designer doesn’t change the revision on the file.  It’s the same filename on the FTP site as was emailed previously to the service bureau. 

Now the bureau has two files downloaded to their system.  Both with the same filename and both contain relatively the same time stamp caused by saving the email attachment at about the same time they downloaded the file from the FTP site.  Rather than being able to quickly quote the part and begin shooting laser beams, they have to spend the time to reconcile the files, also taking up the designer’s time. 

This is corrective action!  What company makes profit on corrective action?  So why have workflows that include corrective action? 

How else can you share files?

Data security is a key question, but so is saving time.  There are some problems with how we commonly share data that may surprise you.  Let’s take a look at the two ways the designer shared his data with the service bureau to see if there is a better option.


Emailing files raises concerns.

  • First, many inboxes will not download large files.  Our designer realized this and that’s why he was forced to using FTP the second time.
  • Second, email protocols don’t compress the data well for electronic transfer, so uploading (sending) and download (receiving) an email with a large attachment can take a long time. Don’t you spend enough time managing email already?
  • Third, eavesdroppers can snoop into an email at any stop through the internet, just like a postman could open and look at a letter during any stop along the route.
  • Fourth, recipients who receive unexpected attachments may think they contain a virus.  Your supplier might not open email attachments until first verifying them via phone call or another message, wasting valuable time.

This list doesn’t include the pitfalls of using email for data management: duplicate copies of files, renamed files and broken links, and loss of revision or version control.  Any one of these causes a problem and results in dedicating resources to corrective action.  And once you send a file outside of your managed environment, it can be forwarded to anyone without your knowing.  Is that the best way to secure your intellectual property?

File Transfer Protocol

I think we can all agree that while emailing files is convenient, it is the worst method to transmit data, both from a security perspective and from a data management perspective.  There is a reason that FTP has been around for so long; it was one of the best methods to transfer large files.  For a while, it was the only method to transfer large files.

Advantages of FTP:

  • Allows secure transfer of large files on an as-needed basis.  Users login and chose when to download large files, it is not done automatically at the next send/receive command.  And you don’t have another email message to deal with.
  • Anyone with a command prompt can access FTP.  Internet browsers and FTP clients enhance functionality.
  • If there is an internet connection, it is likely that a user can access the files on the FTP site.

Disadvantages of FTP:

  • Duplicate files still exist: the original location, on the FTP site, and on any computer that the file was downloaded to.  If multiple users are modifying their local copy of the file, how do changes get reconciled?
  • Some firewalls block the ports typically used by FTP, making the files inaccessible.
  • Requires IT support to setup and maintain an FTP site, including administering usernames and passwords which may be different than your network domain login.
  • Conversations about the files happen outside of the FTP site.  Connecting a conversation to a specific version of a file is difficult.
  • Only people who have software that can open the native file type are able to view or use the contents of the file.  Additional software licenses may be required, third party viewers may need to be installed, or else some personnel may be left out of the loop.
  • Granting access to the FTP site allows full access to everything on that site, including download and uploading files.  Downloaded files are then outside of the originator’s control.

The one thing FTP still has going for it is that it can handle large file transfers better than email.  But that’s about it.  Surely there must be a better method with new millennia technology.

Cloud-based File Sharing

What about cloud-based file sharing apps like Dropbox for Business, Google Drive, or One Drive?  True, these use current security protocols and are therefore less susceptible to hijacking than FTP.  They also contain sole source of information because the file only exists in the data cloud.  While there may be local copies, most hosts instruct the users to not access the local files directly.  Files should only be accessed via the virtual drive or through a web browser.  So what happens if there is no reliable internet connection?  It means there is no access to the files stored on the cloud.

Cloud-based file sharing applications breakdown when functions beyond file sharing come into play, such as collaborative development or data management.  Although the developers of these applications are tuning the features to be more business friendly, files exist in the user’s private cloud, not a general network share, and are only shared with the workgroup when the user explicitly allows them.  While easy to share the file, allowing other coworkers to modify the file proves difficult. With no file locking or control of who has read/write privileges begs the same confusion as having multiple files.

Cloud-based file sharing is more secure and easier to setup than FTP, which is why many users ignore company policy and use their personal account to share business files.  Cloud-based file sharing improves security and eliminates some of the issues with duplicate files, but it still doesn’t improve the collaborative work environment.  The process of file sharing using personal cloud-based applications will still result in corrective action and the costs associated with it.

Cloud-based PDM

There remains one solution, cloud-based PDM.  With cloud-based PDM, the files are stored in the cloud and on the local drive.  The files are synchronized automatically and access to the data is based on rights and roles-based permissions setup in the project of the PDM system.  That means that files can be worked on when offline and synchronized when reconnected, keeping the designer productive and the project team harmonized to the latest version.

Cloud-based PDM uses the latest in security protocols yielding data security greater than what can be achieved by a standard network firewall managed by a busy IT staff.

  • Because it is PDM and not just file sharing, data management is built in.  Archiving, revisioning, and viewing are all possible.
  • Non-CAD users get the same access to the file contents as CAD users, but without the complexity of having to learn CAD.
  • Filename changes and controls are managed within the system, prohibiting broken links in assembly data.
  • And unlike FTP, users can login and view the files but be prevented from downloading them resulting in no unmanaged copies of data floating around for your competition to see.

Cloud-based PDM also has check-in / check-out functionality, preventing two designers from making modifications to the file at the same time.  There is no question as to which is the latest version.  Adding users is as simple as adding their username to a project, so it doesn’t take any specialized IT staff to manage.  Finally, the conversations about files are captured within the PDM system, so notes and feedback about a design are linked with the file.  No more tribal knowledge or looking up old ECOs to determine the logic behind a change.  All the justification is attached to the file, not just the one line Reason for Change.  Design reviews can occur online and with remotely located employees.

Cloud-based PDM isn’t for everyone, though.

  • Those with ITAR restrictions will be limited in options to PDM providers that locally host data and get their systems certified to be ITAR compliant.
  • Users looking for more than data management, such as those requiring complete product lifecycle management (PLM) or integrations with ERP or MES systems will not be satisfied with cloud-based PDM.
  • Cloud-based PDM programs don’t always integrate with a user’s existing design (CAD) or simulation (FEA) software, either.
  • As of this post, I don’t know of any cloud-based PDM system that has SSO support, whereas Dropbox for Business does.

Like any enterprise system, users should weigh all pros and cons of a data management system to be certain it fits their company’s needs.

For most scenarios, it’s time to move on from FTP

FTP may be a protocol capable of handling large file transfers, but it lacks the sophistication required of businesses in the 21st century.  Cloud-base file sharing apps improve on FTP, but they still don’t manage product data well.  Unless you have requirements for a complete PLM system, the only solution is cloud-based PDM.

Let’s face it, when you’re busy figuring out how to dominate the world, or maybe something more obtainable like completing your project on time and under budget, you have neither the time for corrective action nor can you risk unmanaged copies escaping your control.  Secure your data, reduce corrective action, and spend your resources on productive improvements by using cloud-based PDM, like GrabCAD Workbench.

Request a demo at Request Workbench Demo.

See additional information comparing Workbench to FTP.

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GrabCAD has paid a fee to to promote their cloud-based PDM solution.  They have not had editorial input to this post.  – Scott Wertel