Tonido and FileCloud

Texas-based CodeLathe offers two separate variants of its software [13]. Although Tonido is primarily aimed at home users and small businesses, FileCloud addresses business customers with 20 users or more. Both versions are packetized or available as archives for various Linux distributions, Mac OS X, and Windows.

Tonido is also available for the Raspberry Pi. The latter is free for typical private use (up to five shares and five guest accounts), but it can be beefed up with an annual subscription.

Although the data remains on your own systems, you need a Tonido ID (e.g., <user>@tonidoid.com ) for access as a substitute for the otherwise necessary DynDNS service. Although this approach may be convenient for some, it is likely to cause raised eyebrows among self-hosting purists. Worse, Tonido implements its core functions – even on Linux – with closed source binaries.

Commercial License

The FileCloud enterprise solution is also completely under a commercial license. Major parts of the PHP scripts, which run against a MongoDB database, are also protected from scrutiny by ionCube. Any reverse engineering is prohibited in the FileCloud terms of services. The terms also include the condition that FileCloud calls on the provider to look for software updates, and the privacy rules were actually written for Tonido.

In terms of features, FileCloud leaves little to be desired as an FSS solution. In addition to Web UI, WebDAV access, and desktop synchronization, CodeLathe also provides its own Windows application named Cloud Drive that mounts the cloud directly as a drive.

An app is available for Windows Phone, alongside iOS and Android support for mobile access. Outlook users can use a special add-on to free their mail attachments and send sharing links instead. As you would expect for a commercial offering, the documentation is also extensive.

Conclusions: The combination of Tonido and FileCloud is an attractively priced alternative to file synchronization and sharing, assuming that you trust the claims and intentions of the provider.

BitTorrent Sync

Many people only know of Torrents [14] by hearsay in the context of illegal file-sharing activities. However, the peer-to-peer protocol is also suitable by definition for synchronizing your own files across multiple devices or for sharing with other users. The venture-funded BitTorrent Inc. offers software called BitTorrent Sync (Sync or BTSync for short) [15] in addition to the normal BitTorrent client, which offers precisely this functionality (Figure 6).

Figure 6: BitTorrent Sync lets you share files with other computers or devices. This functionality is especially useful for backup purposes.

The free Sync client lets you synchronize data between different computers and systems on the LAN but also – thanks to NAT traversal and UPnP port mapping – on the Internet; this means you can also use it as a home cloud system.

Each instance of BitTorrent Sync optionally acts as a data transmitter (client) or receiver (server). If you have a Raspberry Pi at home running a server instance, it receives the data from the stationary and mobile clients running the client. It has two modes of operation: read-only and full-access mode. In both, BitTorrent Sync keeps the data in sync between the source directory (client) and the target directory (server).

The difference: In full-access mode, BTSync deletes files from the source directory as soon as they disappear from the target directory, but this does not happen in read-only mode. On request, BTSync first pushes deleted files into the .SyncArchive subfolder.

BitTorrent Sync encrypts the data stream with an AES key and a 20-byte security key, according to the manufacturer's details. However, you cannot determine how secure the encryption actually is, because the source code is missing. If you do not trust the encryption, you can also use BTSync purely locally.

The good thing is that BitTorrent Sync runs across platforms and in the background; it is easy to use and also supports mobile clients. Maintaining the software is somewhat time consuming, however, once you have it running on multiple computers. After you upgrade to a new version, you need to set up BTSync again wherever you use it. Additionally, some of the sync processes hung frequently in our ADMIN magazine lab, forcing the admin to set up the server side yet again.

In contrast to the architecture of other FSS solutions, Sync does not require a server. Data is exchanged exclusively between the devices running Sync. Users can share with other Sync users and notify them by email or QR code. Both full control and read-only rights are configurable.

The fact that Torrent handles large files well is known to at least the users of traditional BitTorrent clients. BitTorrent Inc. offers closed source clients for Linux, Windows, Mac OS X, and FreeBSD. For mobile devices, the range extends from Android through iOS to Windows Phone. Sync is also available for some NAS devices (e.g., QNAP and Netgear).

The lack of an option for accessing data without a Sync client somewhat limits the range of applications for the tool. Although users retain control over the systems under their own sovereignty and can also influence shares, they need to trust that the clients do not have any data leaks. The less than fully transparent business model of BitTorrent Inc. – at least in terms of Sync – will typically lead to users developing an alternative plan for their synchronization strategy.

Conclusions: Sync offers robust file synchronization without a server and – restricted – external data sharing but is unfortunately closed source.