BitTorrent reveals Sync, a new file synchronization tool | Hacker News Reader

BitTorrent reveals Sync, a new file synchronization tool

thenextweb.com

111 pointsSami_Lehtinen35 comments

This is what I've been waiting for. A dropbox-like service that uses BitTorrent. Seriously, with the way BitTorrent is integrated into all kinds of services and devices, it would be like instant Dropbox integration, with everything. You could start using the cool Torrent scheduling stuff to, for example, automatically transfer large files to a partner, quickly, as they're produced on the other end. Or to your TV, whatever.

Don't forget about most people's very limited upload speed if they need to access files from a "not-in-sync" client.

Not saying Dropbox download speeds are a lot better, they actually sucked for large files last time I checked.

Of course, if you throw this on a server though, it obviously becomes a very good alternative to Dropbox et al, yet that's not a solution for everybody and you yourself are responsible for keeping the server safe.

This is why it's important to demand symmetric speeds from Internet providers in US. People are uploading a lot of stuff to the Internet these days. It's a much more 2-way medium today than it was in the past.

I use git-annex assistant for that. When a new file appears in a certain directory in my VPS, the Assistant will automatically sync it to my Desktop machine (which has a 2TB disk). When the VPS disk space gets low, a script will run "git annex drop --in=here --in=desktop", which deletes files that have already been copied to the Desktop (but not without first checking if they're there).

Then, on my laptop, I can just do "git annex get [file]" and it'll fetch it from the best source automatically.

Seriously, it's a great piece of software.

Does it work on windows yet?

Not yet. See: http://git-annex.branchable.com/todo/windows_support/

Not according to the website:

http://git-annex.branchable.com/todo/windows_support/

Seconding git-annex.

I haven't used git-annex assistant, but git-annex alone has revolutionized the way that I think about and interact with my filesystem(s).

And where are the files stored? If I create a 'Sync'ed file, switch off the computer and start the laptop, the file needs to be stored somewhere. And if this somewhere is the torrent swarm, then I would expect an interesting discussion on cryptography and (perhaps) fountain codes etc. ( Unfortunately the blog post [1] is even less detailed than OP's submission.)

[1] http://blog.bittorrent.com/2013/01/24/test-bittorrent-sync-p...

I suppose it can be seen as twofold:

1. an AeroFS-like part, i.e your files reside only on your machines and are synced via a P2P protocol, so not-yet-synced files are unavailable when your source is offline (unless like AeroFS, they are opt-in stored in the cloud).

2. a content-hashing part, which means files on your machines that happen to have an identical file elsewhere can be obtained from that elsewhere, even if your machines are offline.

Still, no source => no data, but that's a given.

Technically, 1. is of course a special case of 2. It's just that AeroFS restricts peer requesting to your machines (and — optionally — their cloud storage).

Maybe on a Rhaspberry Pi you keep running somewhere?

Several companies have been using BitTorrent this way to move data in between machines (backups, builds, etc.). This may be inspired by such anecdotes.

Probably. I've been looking for easy ways to share large files between 2 computers, and I've noticed some people were recommending to just create a torrent with utorrent (apparently you can do it just by dragging and dropping the file on utorrent), and then send that person the torrent to download the file.

So I think this has a lot of potential, as a much more secure alternative to "cloud storage" as this is being more like "personal cloud storage".

I guess a big difference is that your data isn't stored at a 3rd party somewhere. That's one of the things that are good about Dropbox - if you delete your stuff, you can go back and fetch it.

It is also one of the things that are bad about Dropbox: even if you delete your files, someone else still has a copy. Worse, it's almost never encrypted client-side.

That is often not an issue of course, Dropbox is great.

Dropbox has its demons, however, and it's probably not something you should rely on for its security.

I used to use it as a means of keeping an encrypted file synced across machines, but when you re-lock up the file it... well, encrypts it, which means re-arranging ALL the bits, so a diff (how dropbox syncs) is just the whole damn file.

> I guess a big difference is that your data isn't stored at a 3rd party somewhere.

I think a word which could be missing here is "necessarily". I see no reason why you couldn't have "remote" sync devices provided by third parties, including but not limited to Dropbox. So if you want to store your data at a third party, you can. If you want a remote storage under your control, you can. If you don't want remote storage, you can.

On your own terms, with your own conditions.

I've tried to hack together something like this but had trouble getting the initial torrent to seed from behind a NAT. After reading up on the BT protocol, my conclusion was that it really works best when you have a large swarm of peers. For sharing a file between my 2-3 devices or with 2-5 friends/coworkers, I want a protocol that works to establish the fastest connection between me and 1-2 other peers (taking advantage of local networks), not one that's designed to peer me with 15 other people. I'd encourage anyone interested in this to check out AeroFS.

Also, I think I had seen an earlier iteration of this that was using some kind of technique where they sucked the data you wanted to share into their seedbox. I wonder how they got around that.

One thing dropbox and other cloud-based sync providers have going for them is that they've solved peer-to-peer NAT fairly well.

I've always thought that the simplest way of solving the problem of "I want to sync an arbitrary amount of content between two computers, and I don't care that it's not available 'in the cloud' when all my machines are off" is to build a communication channel on top of dropbox (or something else). Although it's likely that Bad Things could start happening once your usage profile starts getting attention.

It wasn't "launched", only "revealed".

This would actually be tremendously handy for my geographically-distributed extended family.

For example:

* My mother could see all the pictures we've taken of her grandchild.

* My sister would know that all her PhD research is backup on a computer half-way across the country.

* I don't have to email my wife documents she asks me to scan, because she has everything I scan in her folder, even if she's out of town.

I love Dropbox, but being able to roll my own solution with my own family is great.

Seems similar to AeroFS.

Similar, differences are: real p2p, native code, arm/ppc/x86 versions. Based on uTorrent, so very effective in terms of memory and speed.

And git-annex assistant (http://git-annex.branchable.com/assistant/)

I have been using AeroFS ( https://www.aerofs.com/ ) for a couple months now and it works similarly.

The files sync between all your AeroFS computers (and supports selecting syncing too) instead of to a single server so I basically have literally 100s of GBs of 'cloud'/Dropbox-like storage available. And as a bonus, its completely free for all this 'unlimited' storage.

I just want to know if it does client-side encryption.

AES256 client side

Logmein's Cubby does pretty much the same thing, in same p2p fashion and has an option to get a server-side storage. Doesn't have the cool kid factor associated with BitTorrent, but the point is that the tehnology has long been there and it has been wrapped into the products.

Sync success hinges largely on whether BT can market it well, not on what it does or how it does it.

Interesting. Questions come to mind:

Encryption? (or would that require another layer a-la BozCryptor?)

Error/collision management - when Dropbox syncs files, there is a master repository (Dropbox.com) and a file isn't synched unless it exists there.

How do you think it compares to Crashplan multi backup feature http://support.crashplan.com/doku.php/feature/multi_destinat... ?

As a Crashplan user, I see it as only slightly related. Crashplan is a backup solution, with multiple versions available for restoration. These are stored in a compressed and optionally encrypted blob of folders and files with restoration controlled by Crashplan's GUI.

BitTorrent's Sync application appears to be a way to keep the current version of files syncronized on multiple computers without a cloud (server) intermediary and without a history of previous versions.

Am I missing something? Other people have my files? Peer-to-peer sounds horrifying for my personal files.

I'll take SSL between me and one server, thankyouverymuch, and I'd prefer if 100 different seeders didn't have my personal files!

Or am I only seeding between my own personal machines? I sync to my four devices and I can leech off of any of my own devices connected? But that doesn't seem very "cloud".

Does anyone honestly feel comfortable syncing their files to peers?

Why not just hop on and peer everyone for the sole purpose of harvesting people's files?

Files are stored only on your computers, there is no cloud part. Sync uses p2p to create a cloud from your computers. You will need to care about your setup, to have 24x7 availability of the files.

We do this in Tonido as well. Using your primary computer as a sync server and sync clients in all your other devices.

Your data is completely private and secure. Since it is a sync and have the same files on all your connected devices you really don't need 3rd party cloud storage systems like dropbox. Because often the argument is made for public clouds that it provides offline backup not only sync.

Many small businesses use the product especially who have sales personnel in the field.

Seems like Tonido Sync (http://www.tonido.com/app_sync_home.html)

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