Google Drive vs. Amazon Cloud Drive - My Experience with Cloud Storage

A new year has begun and it is time to reconsider and plan ahead. One of the topics I reconsidered this year was my choice of cloud storage as a friend pointed me to an "irresistible" offer from Amazon. Well, I did some tests...

Pricing

Google Drive with a capacity of 1 TB is currently available for roughly 100 EUR per year in case the service is charged on an annual (as opposed to a monthly) basis.

Amazon Cloud Drive with an "unlimited" capacity is available for 70 EUR per year and charged annually.

So, based on the price comparison, it was worth testing Amazon and compare against Google. My application may not challenge all features of these services as it is simply an off-site mirror backup for my documents and pictures.

Integration

Both services offer apps to tie them into Windows, iOS or Android for uploads and downloads, and both also offer a web interface to browse, manage or upload files.

In addition, there are third-party backup/synchronization clients available under Windows which support the respective native protocols directly (without having to install Google or Amazon software locally) to replicate files from the local hard disks or a connected NAS to the cloud storage.

Performance

Google seems to throttle the bandwidth into the Google cloud (I usually do not run into this from home because my cumulated upstream bandwidth will be less than 10 Mbit/s), the number of concurrent connections (further connection attempts will time out), and the number of new connections per time unit (noticable when many small files are uploaded and several of them fail if uploads are attempted with three or more parallel threads).

Amazon seems to throttle the bandwidth in the same way as Google, but in my tests with a large directory of small icon and image files, I did not observe the effect of a limited number of connections per time unit.

With both cloud services, I could utilize my full upstream bandwidth for the backup. My router actually does session-based load balancing over two independent Internet connections, and the upload scenarios I tested with both cloud services managed to reach full upload capacity.

Reliability

I have tried several different clients for the mirroring backup from local disks and my NAS, and independent of the clients, there was a notable difference between Google and Amazon. The Google uploads would run robustly, except in the case of many small files in several parallel threads. Photos (usually 3-8 MB each) will upload reliably with three parallel threads. This way, a sync of ~140 GB in ~36.000 files worked without a single error. Syncing my clipart for presentations (~3000 image files of mostly a few kB, some in the MB range) worked robustly in a single-thread feed.

Amazon seems to time out every now and then, so some files will not be copied reliably, and to make sure I really have an identical mirror copy of the original file system (including modification times), I have to run the mirroring tool twice or even more often - until there are no further deviations between the two copies. There does not seem to be a correlation with file sizes as the same happened with the clipart collection and the photos. Reducing the number of threads per job to two or even one did not help, so I assume this is a question of either network congestion or some throttling mechanism.

The retrieval of files worked nicely and without errors for both services.

Neither one of the two services comes with an SLA for private customers. Google Apps for Work would bring SLA for Google Drive, Amazon does not have a business offering for Cloud Drive.

Features

There are not many features required for a mirroring backup solution. Both cloud storages support hierarchical directories of files - in contrast to the older Amazon S3. The Windows or mobile apps allow a hierarchical navigation through folders just as usual.

Google Drive does have one annoying feature, though: you can create directories with duplicate names. Using a mirroring tool usually avoids this effect but it can occur and will cause major confusion.

Amazon Cloud Drive is lacking an option to set modification dates of files. Files will always be stored with the time of the upload, as opposed to the original file times on the local file system. To compensate for this, some backup programs (like GoodSync, the one I am using) keep a record of the file times in additional meta data attached to Amazon Cloud Drive files after the file content upload has completed. However, this does not seem to work robustly - in remarkably many cases, there were timeouts and other errors that apparently kept the backup tool from setting this meta data properly. What happens? Well, you end up with a perfect copy of your files on the cloud service, but they all have the wrong modification times. As your backup tool will use this information to determine whether a backup is necessary, it will copy the respective files again. I found that sometimes five and more iterations were necessary to copy directory trees of ~2000 files. That is not my idea of a reliable backup.

Security

Both cloud services have rather rudimentary security/access control features - the ones present are based on a sharing model for files and folders.

While Google claims to disperse file contents as little encrypted pieces all over the world, so no single entity accessing their data centers (though hacking or court orders) would simply be able to retrieve clear-text client files, Amazon seems to keep files together in their data centers with possible replication to multiple locations. Given the high security levels of Google and Amazon data centers, this should normally provide adequate security for ordinary files of private customers.

For more sensitive materials like tax declarations, bank statements or medical records, one should utilize encryption features of synchronization tools or use encrypted containers (e.g., with VeraCrypt) to specifically protect such files beyond the cloud provider's mechanisms.

Conclusion

So, my personal conclusion from a little test over the last days is that I will stick with Google Drive and forget about Amazon Cloud Drive simply because of the modification time misfeature and robustness issues.

My simple requirement for a mirror backup is to run a tool and be more or less sure the job is done when the tool finishes. That was definitely not the case with Amazon Cloud Drive. I had to re-run multiple synchronizations until finally everything was copied and set properly. Amazon Cloud Drive presently does not seem to have the maturity to serve as a mirror backup cloud storage for my purpose, apart from security and privacy issues not addressed.

As a cheap off-site backup, Google Drive seems to be the best value for this price for me at this time.

Whither and Whence

My first experience with cloud storage was Amazon S3 when it became available in Europe. It was not quite what I wanted but a rather cheap off-site storage for documents and photos.

More like the feature set I was looking for was offered by a company humyo where I switched in 2009. Nowadays, I avoid smaller and more startup-like cloud storage providers as they may disappear as quickly as they emerge, or they may be taken over, changing relevant service parameters (e.g., where the storage will be hosted). Humyo was acquired by Trend Micro in 2010 and its successor finally disappeared last year.

After leaving humyo in 2010, I became a happy user of Strato HiDrive, a cloud storage service offered by Strato in Germany and several other countries. Strato worked fine until some changes to the WebDAV services were made in 2013. At this point, my mirroring tools stopped working reliably and I switched to Google Drive, which was not only cheaper but by far more robust and available. It has proven to be stable since then.

An interesting service operating from Swiss data centers and focussing on end-to-end encrypted access at still affordable prices is pcloud.com. They also started offering WebDAV access recently. I have not yet found time to evaluate it, but it certainly sounds like a serious competitor for my Google Drive and so far the closest in meeting my requirements. The 2 TB storage is at USD 95.88 per year, so roughly the same as Google and cheaper than Tresorit, another such service from Switzerland. PCloud service does include a traffic limit, however, it is rather generous.

Let's see... maybe this article is to be continued.