Try it now: We have setup a Sync folder in the BitTorrent office that contains 1.1GB of BitTorrent Featured Content. You are welcome to sync with it by using the following secret key: RWC4YD3S723QRVHHHIZWJXPTQMO6GKEQR Getting started 1. Install BitTorrent Sync on the devices you want to sync 2. Choose a folder that you want to synchronize and generate a secret for that folder on one of the devices. The secret is random and unique, and functions like a key that connects multiple devices into one sync network. 3. On the other devices, choose a folder to sync and enter the same secret. 4. Leave BitTorrent Sync running on all devices you want to keep in sync 5. Manage your sync folders at any time via the application interface on Windows and Mac, or via the WebUI and config file on Linux. Choosing folders BitTorrent Sync allows you to synchronize any number of folders and files of any size. To add a new folder to Sync, at the bottom of the Folders tab, click on the + button (Mac) or Add button (Windows). Choose any folder on your computer or external drive (note that you need to have proper permissions to modify the folder). If the folder doesn t exist, you can create a new folder anywhere on your computer.
Generating/Using a Secret Folders that sync are connected by a common secret--a private key that is unique for every sync folder. If you initiate a sync network, click Generate to create a new secret. This secret must be then entered on all the devices you want to sync. If you are joining a sync network, enter an existing secret that someone has shared with you.
If you need to find the secret later on, it can be found by right-clicking on the folder in the Folders tab, and copying it to the clipboard, or looking on the advanced tab in folder preferences..
One-way synchronization If you want to sync information from your computer only (and not the other way round), you can do it using a read-only secret. Use case? The read-only secret can be found by right-clicking on the folder in the Folders tab, opening folder preferences, and clicking on the Advanced tab. Any device setup using the read-only key will be fully synced, but no changes will ever be copied back to the original device. You can use read-only secret in combination with the master secret depending on what type of access you are willing to grant to other devices. Devices with read-only secrets cannot generate their own secrets for a folder. One-Time Key (secret) For security reasons, you may not want to publish a master secret. In this case you can create a one-time key that can be used only once and expires after 24 hours. This can either be a full access or a read-only
key that is created on the base of the master secret. After the one-time key is entered, the device will receive a permanent full access or read-only secret for the sync network. Application Preferences You can set your preferences for the application in the Preferences tab in the main window. Here you can change the name of your computer as it is shown on other devices, configure updates and notifications, change the listening port and map it using UPnP, as well as set limits for total upload and download speeds.
Folder preferences Apart from changing settings for the whole app, BitTorrent Sync lets you fine-tune preferences for each folder. They can be accessed by double or right click on a folder in the Folders tab. General Tab BitTorrent Sync is preconfigured to ensure best performance, but feel free to change settings according to your needs: The relay server is used only when it is impossible to connect to other devices directly due to NAT issues. The tracker server facilitates communication and discovery between devices. Delete Files to Sync trash saves all the files deleted on other clients to a hidden.synctrash folder. If you uncheck this option, deleted files will be moved to system Trash\Recycle Bin (depending on your OS). Use predefined hosts is an option to specify ip:port or host:port of known clients. This way, if one of your devices has a static and accessible IP, peers can connect to it directly.
Advanced Tab Advanced folder preferences is the place where you can copy, change or generate new secrets for your sync folder. Secret is a 32-character master key for connecting folders. All the folders added with this secret will be granted a full set of permissions for two-way synchronization. The master secret can be changed at any time or replaced with a custom Base64 string more than 40 symbols long (any change to the folder secret needs to be re-entered on all the devices in the sync network). Read only secret is generated on the basis of the master secret and is used for one-way synchronization. Any folder with the read-only secret will be fully synced, but changes made in the folder will never be synced back to the original device. It is also not possible to manage secrets for the folder if access to the folder is granted by a read-only secret. One-time secret/key is a security option available for the folders operated by a master secret. You can generate either a full access or read only short key (16 characters) which can be used only once and should be activated within a limited period of 24 hours. When connected, a folder added with a one-time secret will receive a permanent master or read-only secret from the device where the one-time secret was generated. Linux and NAS WebUI WebUI is the default way of accessing BitTorrent Sync. It can be reached at YourLocalIP:8888/gui You can manage both general and folder preferences via WebUI the same way as from a desktop application. Сonfig File Config file offers a slightly wider variety of options to configure. It is a JSON format file.
1. Get a sample config by running --dump-sample-config. You ll see a list of options and commentary. 2. Save config file to any desired location. For example, to save it to the current directory, run:./bittorrent Sync --dump-sample-config > sync.conf 3. Customize the settings and run BitTorrent Sync with the modified config. For example, if your config file is in the same directory with BitTorrent Sync, run:./bittorrent Sync --config sync.conf Before running BitTorrent Sync with config file, make sure it is a valid JSON. Otherwise, you ll get an error message. Frequently Asked Questions (FAQ) Can other BitTorrent users see my shared files? No. BitTorrent Sync is based on BitTorrent protocol, but all the traffic is encrypted using a private key derived from the shared secret. Your files can be viewed and received only by the people with whom you share your private secret. What is a Secret and how does it work? A secret is a key that connects different devices and joins them together. We automatically generate secrets to ensure their uniqueness. Since each secret is 32 characters long, it is virtually impossible for the same secret to be automatically generated in two separate instances. After a folder is added to BitTorrent Sync, the Secret is stored in its advanced preferences and can be accessed by double or right click on a folder in the Folders tab. There are 3 types of secrets: master (full access) secret, read only Secret for one-way sync and one-time secrets (both full access and read-only). Read only and one-time secrets may be generated only for folders operated by master secrets. If you are concerned about security, BitTorrent Sync provides opportunity to regularly generate new
Secrets for a folder, or replace an existing secret with your own Base64 string more than 40 characters long. The new folder Secret should be re-entered on all the devices in sync. What happens if a file is deleted or changed on one of the devices? Files deleted from a sync folder on your computer are handled depending on your OS preferences (moved to Trash/Recycle Bin/similar folders or deleted completely). On the other syncing devices these files will be moved to the.synctrash in their sync folders (.SyncTrash is hidden by default). What if several people make changes to the same file? When a file is changed on one of the devices, it will be recreated as a new copy and synced to the other devices. We save only the latest version of the file. What if files with same names are added from different computers? If several users add a file with the same name, BitTorrent Sync saves only the file that was added last. What happens when I remove folder from BitTorrent Sync? If a folder is removed from BitTorrent Sync, all the synced files stay there; incomplete files with the.! sync extension will be deleted. Does BitTorrent Sync support versioning? Currently versioning is not available. We are planning to add it in the future versions. Is one-way synchronization possible? Yes, starting from the version 1.0.95 BitTorrent Sync features one-way synchronization. It is established via read only secret (permanent or one-time). Any folder with a read-only secret will be fully synced, but changes made in this folder will not be synced back. Do I have an option to ignore some files during sync? If you have files in your sync folder that you don t want BitTorrent Sync to track, you can use.syncignore..syncignore is a UTF-8 encoded.txt file that helps you specify single files, paths and rules for ignoring during the synchronization job. It supports? and * wildcard symbols. Note that.syncignore is applied only to the folder where it is contained and will not work with the files that have already been synced. If you add indexed files to.syncignore, they will be deleted on other syncing devices. In order to avoid this: 1. Quit BitTorrent Sync or remove the folder from sync on all the devices. 2. Modify.SyncIgnore file on all of them so that it contains same info. 3. Run BitTorrent Sync or re-add the modified folders.
Technology Secret The secret is a randomly generated 21-byte key. It is Base32-encoded in order to be readable by humans. BitTorrent Sync uses dev/random (Mac, Linux) and Crypto API (Windows) in order to produce a completely random string. This authentication approach is significantly stronger than a login/password combination used by other services. That's why using a secret generated by BitTorrent Sync is very safe and secure. If you want even more security, BitTorrent Sync gives you a way to use a custom secret of any length you want. Just create your own secret of any length, encode it with Base64, and enter in the secret field for BitTorrent Sync. Servers Sync is the first synchronization tool that can run completely without servers or inside your LAN without any internet access. However there are cases when servers help and we are going to describe such cases below: Peer Discovery In order to find proper peers that have the same secret, Sync uses: Local peer discovery. All peers inside local network are discovered by sending broadcast packets. If there are peers with the same secret they respond to the broadcast message and connect. Peer exchange (PEX). When two peers are connected, they exchange information about other peers they know. Known hosts in folder settings. If you have a known host with a static ip:port, you can specify this in Sync client, so that it connects to the peer using this information. DHT. Sync uses DHT to distribute information about itself and obtain the information about other peers with this secret. Sync sends SHA2(Secret):ip:port to DHT to announce itself and will get a list of peers by asking DHT for the following key SHA2(Secret) BitTorrent tracker. BitTorrent has a specific tracker server that helps peers discover each other. It also sees combination of SHA2(secret):ip:port and just helps peers connect directly. Another application of BitTorrent tracker is as a STUN server to do a NAT traversal for peers. It helps peers tbehind NAT to establish direct connection. This can t be done by DHT, so even if peers can talk to DHT, they won t be able to talk directly. We do recommend that you use a tracker server rather than DHT for the reasons of faster response and NAT traversal, so peers with higher probability could talk directly.
Relay Server There are rare cases when peers can t talk directly. This usually happens when devices are in an office behind good firewalls. In such a case BitTorrent provides a relay server to route traffic between peers. All traffic is AES encrypted with your Secret, so there is not even a theoretical chance for us to see anything inside. You could opt out of this, but it could introduce (=result in?) the case when peers won t be able to talk to each other. As you can see, BitTorrent Sync offers a lot of configuration options to make sure you achieve what you need. Default Sync settings are based on our extensive experience in networking and p2p and are best suitable for the majority of cases. Platforms At the moment BitTorrent Sync works on Windows, Mac and Linux devices that meet the following system requirements: Mac OS X Snow Leopard or later Windows XP SP3 or later Linux with kernel 2.6.16 (glibs 2.4) or newer on ARM/PPC/i386/x86_64 You can install our app on Network Attached Storages (NAS) running on Linux with ARM, PowerPC, i386 and x86_64 architecture. In the future releases we plan to add versions for the most popular mobile platforms. P2P Protocol BitTorrent Sync synchronizes your files using a peer-to-peer (P2P) protocol. This protocol is very effective for transferring large files across multiple devices, and is very similar to the powerful protocol used by applications like µtorrent and BitTorrent. The data is transferred in pieces from each of the syncing devices, and BitTorrent Sync chooses the optimal algorithm to make sure you have a maximum download and upload speed during the process. The devices you setup to sync are connected directly using UDP, NAT traversal and UPnP port mapping. We also provide such additional methods of ensuring connectivity as relay and tracker servers. If your devices are on the same local network, BitTorrent Sync will use your LAN for faster synchronization. Security BitTorrent Sync was designed with privacy and security in mind. All the traffic between devices is encrypted with AES cypher and a 256-bit key created on the base of the secret a random string (20 bytes or more) that is unique for every folder.
It s our priority to make sure that nobody has unauthorized access to your folders. That s why there are no 3rd party servers involved when syncing your files. All the files are stored only on your trusted devices, controlled and managed solely by you. For the same reason we provide you with an agile way of managing secrets. You can regularly change them and invite people by sharing a one-time secret instead of distributing a permanent one.