BitTorrent Sync beta brings mobile support and versioning

BitTorrent's Sync decentralized file-synchronization tool has entered beta status, and offers a number of enhancements, including support for mobile devices as well as a new versioning feature called SyncArchive.

Following months of closed testing, on April 23, 2013, BitTorrent released a public alpha version of its Sync software, a cross-platform competing service to online storage and synchronization solutions such as Dropbox, Google Drive, and Apple's iCloud. Unlike its competitors, Sync approaches synchronization using the decentralized BitTorrent peer-to-peer (P2P) network, which avoids the need for hosted storage space as a transfer medium, and instead keeps paired folders directly synced between devices, regardless of where they are in the world.

Users got a taste of Sync's capabilities with the alpha release; BitTorrent saw wide adoption with over 8 petabytes (8 million gigabytes) of data synced across devices by users over the past three months. With the beta version released today, BitTorrent aims to expand its user base and has added a couple of enticing features to the program:

1. SyncArchive
   This feature is a new versioning routine, which keeps past renditions of documents that are synced between devices. If a document is edited on one device and thereby updated on all paired devices, this feature will preserve the most recent version of a changed document in a hidden folder that can be accessed through the Sync interface panel. In its current form, SyncArchive only keeps one past version of a given document, but BitTorrent mentioned that this feature is a work in progress, so it will likely expand to include multiple versions of documents, among other features.
2. Mobile support
   Another new feature with the beta is support for mobile phones and tablets. Currently there is an Android client available (through Google Play), though an iOS client is in the works and is expected to be released soon. With these additions, Sync offers a cross-platform solution and can keep files maintained across Windows, OS X, Linux, iOS, and Android devices.

Beyond these features, Sync offers file-specific handling options like one-way synchronization, and file and folder exclusions lists, to help you tailor which files are synced and which are not.

BitTorrent's decentralized approach for synchronization is unique in that there are no accounts, subscriptions, or reliance on third parties for managing your files. This offers several enticing benefits over alternative options.

First off, while some may enjoy having a company behind their cloud-based storage, others might be skeptical about privacy and file security -- especially given that data entrusted to an account on external servers can be stored anywhere in the world -- and (regardless of argument about rarity and unlikeliness) worry that their information can technically be accessed by the hosting company and passed on to governments and other third parties. BitTorrent Sync keeps your files on your devices only, with all transfers between devices being secured using 256-bit AES encryption.

Additionally, the software is built to be persistent, meaning that it does not depend on a parent company to stay in business and keep its servers running. Even though Google Drive and Dropbox are expected to be around indefinitely, should some problem happen, these services could experience an outage or be shuttered entirely, whereas the decentralized nature of BitTorrent Sync means that it will persist as long as an Internet connection is available (or simply a Wi-Fi or Ethernet connection for local network syncing).

Finally, Sync is only limited by the storage space you have available on your system, and perhaps by the transfer limits (monthly or otherwise) imposed by your ISP. If you have been frustrated by the 2-5GB storage limits for popular cloud-based options, Sync offers a free way to get maximal data storage and allow you to expand it at your leisure.

Though these perks may be enticing, one drawback of BitTorrent Sync is the lack of a hosted backup service. In the event that files are lost and can't be found in your sync folder, companies like Dropbox offer options to access backed up files, whereas Sync requires you to maintain your own backups. This is relatively easy to do with services like Time Machine for OS X, where you can even set up a dedicated server to host a sync folder that is regularly backed up, but some may prefer to have this handled by their synchronization service, especially if they solely work on mobile devices and rarely use a computer.

Given BitTorrent Sync uses the BitTorrent network, there may be confusion and suspicion that even in encrypted form files may be distributed and stored among different anonymous computers -- but this is not the case. For classic BitTorrent file sharing, a TORRENT file allows one client to request data from another and thereby permit access to data; however, with BitTorrent Sync this authorization is managed and secured by an encrypted 32-character unique "secret" that limits requests to clients configured with this secret.

This setup prevents unauthorized BitTorrent network clients (Sync or otherwise) from requesting your data, so the BitTorrent network is only used as a means for establishing a connection between your devices, and not as a means for transferring your files. However, while P2P technologies are the default behavior, you can set up each folder you sync to use specific subsets of available connectivity options, including limiting connections to predefined hosts only.

Overall, BitTorrent Sync offers a free, alternative approach for keeping your files with you wherever you go, be it on your desktop or laptop using OS X, Windows, or Linux, or on a mobile phone running either Android or iOS (coming soon).

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