BitTorrent Sync 1.2 introduces API and performance improvements

Martin Brinkmann
Nov 5, 2013
Updated • Apr 27, 2015

BitTorrent Inc. launched the new BitTorrent Sync file synchronization application based on BitTorrent technology back in January. We managed to gain access to a private alpha version of the application and published our first review in February of the same year.

Public alpha versions for desktop PCs and Android were released a couple of months later, with the PC version reaching beta status back in July 2013.

Today the company announced that it has updated BitTorrent Sync to version 1.2. While still in Beta, the new version ships with several improvements over the previous version.

Users of the application benefit from improved sync performance while syncing files on local area networks. Sync speeds doubled to nearly 90 MB/s on networks according to the company, and while that will certainly vary depending on how the network is set up, it is definitely a step in the right direction to increase the appeal of the application to a larger audience.

BitTorrent Sync 1.2

According to the company, more than 1 million active users use BitTorrent Sync each month. Since the release of the beta in July, more than 30 petabyte of data have been synchronized using the application.

Is that a lot? 30 Petabyte are 30,000 Terabyte or 30,000,000 Gigabyte which sounds like a lot. If you divide it by the number of active users, you get a total transfer rate of 30 Gigabyte per user over the course of the beta.

Probably the most exciting news is the integration of an API that developers can make use of to distribute data on the platform.

Today, we’re releasing the BitTorrent Sync Beta API. The new API will allow developers to create distributed social media, communications, and enterprise apps on top of the platform. It’s designed to work across major operating systems; including Windows, Mac, and Linux.

Some of the possibilities that the API introduces are options to store encrypted file copies on a remote server so that users can create their own private and secure cloud, options to integrate Sync into a different user interface, or support for selective synchronization.

The API just like the main program is available as a beta version right now. Interested developers can check it out here on the BitTorrent Sync website.

One of the appeals of BitTorrent Sync is that it does not require a central cloud-based server to synchronize files. While that means that the computer systems need to be connected to the same network or reachable on the Internet, it adds extra protection to the process as data is not stored on third party servers.

Then again, the service is closed source which will surely keep privacy conscious users away as many prefer Open Source solutions that they can vet before use.

Closing Words

It is clear that BitTorrent Sync is not made for all synchronization needs, at least not in its current state. It has its appeal to users who want to sync data without having to go through a central server but is not really an option right now for users who want data to be available in the cloud at all times as well.

Development is progressing in a steady pace though, and it is likely that other missing features such as file versioning will make an appearance in future versions of the application. It does not necessarily have to be as part of the official client though, as third party developers can now make use of the API to create their own programs and services around this.

Now Read: BitTorrent Sync for Android, a first look

BitTorrent Sync 1.2 introduces API and performance improvements
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BitTorrent Sync 1.2 introduces API and performance improvements
A first look at the BitTorrent Sync 2.1 update that introduces an API and performance improvements.

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  1. XenoSilvano said on November 6, 2013 at 9:08 pm

    I really like this program, it has a very small file size and is very simple to operate.

    I mainly use it to back up my files to another computer as redundancy fail safe over a wifi router, I also use it to share program updates between computers. (Now lets just hope that both my main and backup computers won’t suffer from a sudden tandem catastrophic drive failure.)

    One aspect which I think is somewhat inefficient about BTsync is the way it handles the files that are moved around within folders that are inside the main sync folder that is being synced.

    Whenever a file is moved from one folder to another folder (folders that are within the main folder being synced), what BTsync does is it deletes the file which ‘already exists’ on the ‘other’ computer that is being synced, then it begins to resync the file from the computer that initiated the file relocation to the newly designated location to the other computer, which if you got my analogy, is a rather inefficient procedure. My question is: if the file already exists on the other computer why not simply send a command to that other computer to move the file in question to the newly designated location, why sync the file again?

    I’m assuming that there is most likely some sort of technical limitation for this. The reason I would prefer a more efficient procedure for this process is because my wifi router is limited to 1.8 MB/s transfer speeds therefore resyncing a file that already exists on the other computer, theoretically speaking, would add more congestion to other newly created files that could be waiting to be synced, ultimately this is inefficient.

    1. XenoSilvano said on November 6, 2013 at 9:20 pm

      If I may add, just like any other sync software, BTsync can sometimes suffer from transfer conflicts that can cause undesired operations as well, I’ve had occasions where data from the computer receiving transfer data had sent old data back to the computer where the data had originated, that sucks, luckily deleted files are archived in the .SyncArchive by default.

      Although this is not the case with BTsync, I really do not like it when transfer speeds are advertised in bits rather than bytes, which is obviously just a ploy to mislead people into thinking that the values are more impressive than they really are given how easily people can conflate bits with bytes (my wifi router is advertised at 15 mbps = 1.8 MB/s which is but a tickle for my SSD), measuring transfer speeds in bps is like gauging speed in km/m (100 km/m = 1 km/h, for those who have a grasp of the metric system). The common place metric in which files sizes are most commonly represented are in bytes not bits.

      1. XenoSilvano said on November 6, 2013 at 11:12 pm

        Actually, scratch the first paragraph of my previous common, that was a major screw-up on my part, don’t try to sync downloads from torrents while they’re in the process of download kids, its not a wise thing to do unless you want to see all your downloads continuously revert back to 0.

  2. niel said on November 6, 2013 at 7:09 am

    I am a BitTorrent user and would really appreciate the company if it gives us useful features like file versioning in the near future.

    1. F. D. Bryant III said on November 6, 2013 at 7:52 am

      Actually Bitorrent Sync does support versioning, from the FAQ:

      Does BitTorrent Sync support versioning?

      “Yes, versioning is available in BitTorrent Sync. It creates and stores all the old copies of edited files for the period of 30 days (this default period can be changed in General advanced preferences – sync_trash_ttl). The versions are stored in the hidden .SyncArchive directory within your sync folder that you can open by right click on the sync folder and choosing ‘Open SyncArchive’.

      Old versions of a file are marked by adding numbers to its name, where the file with the highest number is the latest.”

      Something more robust might be desired, but it is there.

      1. Martin Brinkmann said on November 6, 2013 at 9:18 am

        Thanks, I have corrected this in the article.

  3. insanelyapple said on November 5, 2013 at 7:33 pm

    How they get the amount of synchronized data and number of users actively using bt sync, since they were claiming that application is not using their servers and everything is encrypted?

    1. Martin Brinkmann said on November 5, 2013 at 10:05 pm

      Good question. It may be reporting Telemetry data, but that is just a guess.

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