Space Monkey: Taking the cloud out of the datacenter(kickstarter.com)
kickstarter.com
Space Monkey: Taking the cloud out of the datacenter
http://www.kickstarter.com/projects/clintgc/space-monkey-taking-the-cloud-out-of-the-datacente
24 comments
Without much more technical detail, it's hard to say if this is technically sound, but I've never seen a tech project better suited to Kickstarter. Here's a product that absolutely depends on having lots of early adopters, and using Kickstarter means that unless it has those adopters, you won't be investing in its inevitable failure.
I don't get it. How does it work?
How big is the hard drive in there? Judging from the price, the disk inside can't be much bigger than 2TB. That means if I have 1 TB of data and all the other have 1TB of their own data, it can only "replicated" exactly once (unless there are dedicated "cloud" servers involved), Which means, if my device breaks all devices which received a portion of my data need to be online for me to restore the content.
How does the encryption work? Surely the AES key can't be stored on the device - if it breaks your data is lost. If it's stored in the cloud it's not any safer than cloud storage.
How big is the hard drive in there? Judging from the price, the disk inside can't be much bigger than 2TB. That means if I have 1 TB of data and all the other have 1TB of their own data, it can only "replicated" exactly once (unless there are dedicated "cloud" servers involved), Which means, if my device breaks all devices which received a portion of my data need to be online for me to restore the content.
How does the encryption work? Surely the AES key can't be stored on the device - if it breaks your data is lost. If it's stored in the cloud it's not any safer than cloud storage.
Your argument is mostly valid, but it assumes a couple of premises that are likely to be false:
1. All (or even most) users fully utilize their entire 1 TB quota. In reality, the vast majority of users will probably not even use half of their quota. By the time that changes, hard drive technology is likely to have advanced, and they can start selling larger boxes. Then the cycle repeats.
2. The data on the drives is not compressible. While people certainly could store only compressed files, that's not very convenient, and the reality is that most people will have at least some portion of content that is readily compressible.
Just by exploiting those two facts, the network can probably work without any external cloud assistance. But the smart way to design it would be to also have traditional cloud storage as a fallback. And that would be safer than traditional cloud storage, while still saving money since the fallback would only be used in special circumstances.
1. All (or even most) users fully utilize their entire 1 TB quota. In reality, the vast majority of users will probably not even use half of their quota. By the time that changes, hard drive technology is likely to have advanced, and they can start selling larger boxes. Then the cycle repeats.
2. The data on the drives is not compressible. While people certainly could store only compressed files, that's not very convenient, and the reality is that most people will have at least some portion of content that is readily compressible.
Just by exploiting those two facts, the network can probably work without any external cloud assistance. But the smart way to design it would be to also have traditional cloud storage as a fallback. And that would be safer than traditional cloud storage, while still saving money since the fallback would only be used in special circumstances.
also getting multiple levels of redundancy doesn't necessarily need 1 X redundancy_level physical storage. see:
http://en.wikipedia.org/wiki/Erasure_code and
http://en.wikipedia.org/wiki/RAID#Comparison
Does this work with encrypted data, though? Properly encrypted data is indistinguishable from random data...
yes, the concept of erasure codes just works with the raw bits. so it would work equally for encrypted/unencrypted data from the wikipedia page, it "transforms a message of k symbols into a longer message (code word) with n symbols such that the original message can be recovered from a subset of the n symbols"
Perhaps they encrypt your unique personal files, but share duplicates among all the users? In one tb, there must be a lot of common mp3s, movie files, etc.
Dropbox does this too. I think I read somewhere that they md5 your file and see if matches one already on the network, if so, they just replicate a 'link' to that file in your account.
That's why sometimes if you upload a movie you downloaded, it uploads in a matter of seconds.
That's why sometimes if you upload a movie you downloaded, it uploads in a matter of seconds.
I thought they changed that because someone found that if you added that hash to your Dropbox to your local Dropbox database/config, it would download the movie. And for a week or two, people were pirating movies this way.
Though I suppose Dropbox could still use the same deduplication while making it harder to link a file to your account.
Though I suppose Dropbox could still use the same deduplication while making it harder to link a file to your account.
I believe they broke that scheme using other methods, which I can't recall.
Edit: They changed how it works on the server side, without going into detail. It's discussed here: https://news.ycombinator.com/item?id=2483053
Edit: They changed how it works on the server side, without going into detail. It's discussed here: https://news.ycombinator.com/item?id=2483053
I think this is a step both in the right direction, and the wrong direction. This attempts to mitigate issues with cloud storage by giving you hardware to keep (actually a really good idea! It reduces latency and allows for file recovery) but the service is still controlled by a company/central hub. If the hub fails, the system fails. We need a system that works fully distributively (and preferably open source so anybody can add more nodes)
Also, there's really no reason for this to be a special device. It easily be a blob on your computer's hard drive. An availability problem for laptops, but you'd best have that problem solved anyway since residential internet connections aren't exactly 100% uptime affairs.
Also, there's really no reason for this to be a special device.
It will vastly increase reliability, though. I can think of many reasons why having it on a general purpose hard drive is a really bad idea (turned off accidentally, freezes due to bad apps, virus infection, etc, etc).
It will vastly increase reliability, though. I can think of many reasons why having it on a general purpose hard drive is a really bad idea (turned off accidentally, freezes due to bad apps, virus infection, etc, etc).
Come to think of it, there's really no reason you couldn't do both, and I wonder if this system does.
It's 100% an availability problem, and integrity of the network is important. Desktops/laptops would give ~20% availability, a dedicated device will give ~80%. Think of how much the common user leaves a computer on vs a router or NAS.
You would probably want to build in some kind of automatic reputation system. You wouldn't want people to be able to use more space than they are making available to other people and nodes that are temperamental or have bad availability would drop in reputation and therefore not be relied on as much (You probably want to distribute data over both high reputation and low reputation nodes).
In general although I like the idea of an open source version of this I think the problem becomes so much harder as you don't have a central authority to prevent misuse of it and therefor have to build that into the protocol from the beginning.
Hmmm, I think this may be one of those wedges that gets stuck in my brain and ticks over for a while. Its quite a fun problem to try and solve.
In general although I like the idea of an open source version of this I think the problem becomes so much harder as you don't have a central authority to prevent misuse of it and therefor have to build that into the protocol from the beginning.
Hmmm, I think this may be one of those wedges that gets stuck in my brain and ticks over for a while. Its quite a fun problem to try and solve.
I absolutely agree, but I don't think it would be all that difficult to have a network of peers judge the reputation of a node. Yes, it would be possible for individuals to inject bad information, but unless they can compromise an extensive portion of the network, that information would be overridden by that of legitimate nodes. Then all you have to do is make it so that it would cost more to compromise the network than you would gain by compromising it.
If bitcoin can use a peer-to-peer system to come to a consensus on the validity of financial transactions, it should be possible for a peer-to-peer cloud storage system to come to a consensus on how reliable a node is, and how valuable it is to the network.
If bitcoin can use a peer-to-peer system to come to a consensus on the validity of financial transactions, it should be possible for a peer-to-peer cloud storage system to come to a consensus on how reliable a node is, and how valuable it is to the network.
That's exactly what we're building at https://degoo.com
Interesting. So what are you doing in terms of samwillis' comment about user reputation?
Also, there's really no reason for this to be a special device. It easily be a blob on your computer's hard drive
Uh... If it was on your computer's hard drive and your hard drive failed, it wouldn't be much use as a backup system, would it?
Uh... If it was on your computer's hard drive and your hard drive failed, it wouldn't be much use as a backup system, would it?
The point is that your backups would be replicated to blobs on other people's hard drives, so you'd still be able to recover your data.
Whoops, I understand now! Thanks.
This sounds like http://www.wuala.com/
You can do this with CrashPlan for free today.
File stores like this have been pretty common place for a long time now actually -- systems like Freenet, WASTE, etc.
Interesting to see someone stepping up and delivering a consumer-friendly experience on top of such technology. It's incredibly useful but reliant on a healthy network of peers. A plug-in-and-forget solution with good clients that integrate well into the ecosystem of devices we use today, I think, is very clever.
I'd prefer to see something open-source but this is definitely a step in an interesting direction. Personally I limit my use of "cloud," services because I don't trust other people hosting things like my contacts list, calendar appointments, etc. I do see the benefit and convenience of such services though and if this device/service is capable of synchronizing more of that data from my applications between my devices I would buy into it in a heartbeat.
I hope the kickstarter goes well and this thing takes off (or something similar... again, open source is preferable).
Interesting to see someone stepping up and delivering a consumer-friendly experience on top of such technology. It's incredibly useful but reliant on a healthy network of peers. A plug-in-and-forget solution with good clients that integrate well into the ecosystem of devices we use today, I think, is very clever.
I'd prefer to see something open-source but this is definitely a step in an interesting direction. Personally I limit my use of "cloud," services because I don't trust other people hosting things like my contacts list, calendar appointments, etc. I do see the benefit and convenience of such services though and if this device/service is capable of synchronizing more of that data from my applications between my devices I would buy into it in a heartbeat.
I hope the kickstarter goes well and this thing takes off (or something similar... again, open source is preferable).
It isn't quite obvious from the kickstarter, but it doesn't seem to be decentralized and anonymous like Freenet (dont know about WASTE), which I thought was the main point of Freenet.
How much of your terabyte is yours? The duplication seems to be at least three times (more?), so that would be 333GB. Note: it doesn't matter how finely you cut it up, you need duplication to avoid loss.
It can be ameliorated by the cloud tricks of compression and git-like copy-detection across nodes (people downloaded the same movie, music, image, document, software etc) giving aggregate savings.
Of course, most people won't use their full quota initially, and meanwhile more adopters come online with fresh excess capacity... a kind of ponzi-scheme/chain-letter (to be fair, as drive prices fall over years, units will likely become 2TB, 4TB etc).
It can be ameliorated by the cloud tricks of compression and git-like copy-detection across nodes (people downloaded the same movie, music, image, document, software etc) giving aggregate savings.
Of course, most people won't use their full quota initially, and meanwhile more adopters come online with fresh excess capacity... a kind of ponzi-scheme/chain-letter (to be fair, as drive prices fall over years, units will likely become 2TB, 4TB etc).
except you can't deduplicate against what other people have backed up (multiple people backing up the same movie, etc) and encrypt your backups. If my backups are being put on a device owned by someone else, I want that encrypted so they can't read it.
The whole terabyte is yours. The device has extra capacity to account for the rest.
from the kickstarter page "For $10 per month, you get a full Terabyte (1000 Gigabytes) of storage you can use anywhere, any time". the devices' actual capacity is larger.
I met these guys when they launched at either Calacanis' Launch.co or Arrington's Disrupt. I remember them winning the event too.
Good idea, but I question the scalability of the solution. How does deduplication work on remote devices if you have a lot of them. Is there a checksum of the file against a central server? Curious.
Good idea, but I question the scalability of the solution. How does deduplication work on remote devices if you have a lot of them. Is there a checksum of the file against a central server? Curious.
They launched and won the Launch Conference. That doesn't necessarily de-risk their plans from a technical perspective, but they got some validation from those who vetted the team and product already on the conference and judges panel side of things.
They also had already raised funding prior to going on stage :/. I like this idea but there's a lot of technical hurdles that I never hear answers to :(.
Peer to peer backup? Reminds me too much of Skype Supernodes.
The premise is sound but in reality you're paying $10 a month to help distribute other people's data via your own bandwidth? This goes both ways, of course, but how long until someone finds a way to make their SpaceMonkey exclusively a network leecher, only fragmenting owner's backup but not delivering other people's data?
I could be entirely wrong, of course, someone correct me please.
I could be entirely wrong, of course, someone correct me please.
Doesn't need to be "hacked" - you just need to constantly churn your 1TB while someone else puts 500MB up and adds a photo a month. Effectively you are leeching.
Correct me if I am wriong but this is storing data as torrents and each device is a torrent client and store box?
Correct me if I am wriong but this is storing data as torrents and each device is a torrent client and store box?
You're right. People could do that to save their upload bandwidth, because unless you route your network through the device it can't know how much of your bandwidth it's stealing and if you're currently using it etc. I suspect most of the target audience doesn't have QoS properly setup in their routers.
I'm not sure how valid the torrent analogy is in this case.
I'm not sure how valid the torrent analogy is in this case.
There's really no question about whether or not it will get funded in my mind; the early-bird option alone (which is half sold out) will take them to 50K - half of their goal. I bet this funds today.
Is this just a fancy interface to Tahoe-LAFS? https://tahoe-lafs.org/~warner/pycon-tahoe.html
I suspect this as well - the part where they talk about "even if half of the remaining nodes disappeared" makes me think that a Tahoe (or tahoe style) technology is behind this.
Interestingly, the Tahoe people have their own product to offer:
https://leastauthority.com/
... although I have no idea what state of production that is in ...
Interestingly, the Tahoe people have their own product to offer:
https://leastauthority.com/
... although I have no idea what state of production that is in ...
No. Although being a distributed network with similar reliability and availability and performance requirements, there are some similar technologies/approaches at play.
I'm waiting for the day that a hacker takes over their central update server and bricks all devices worldwide and makes them non-upgradable (or makes them into bots).
How would you deal with that? Ask them all to send it in?
Not sure if I like this. $10/month for a TB is the same as Amazon glacier. Sure that's not the same since Glacier is for archival but still... It's not THAT cheap.
Not sure if I like this. $10/month for a TB is the same as Amazon glacier. Sure that's not the same since Glacier is for archival but still... It's not THAT cheap.
(a) I think that's the same problem that all consumer devices have that "phone home" for updates; game consoles, TiVos, smart TVs, VoIP phone adapters, etc.
(b) If all you need is archiving of your stuff, and you don't want ongoing fast access to your movies, music, photos, etc., then sure. Glacier is probably a better fit.
(b) If all you need is archiving of your stuff, and you don't want ongoing fast access to your movies, music, photos, etc., then sure. Glacier is probably a better fit.
Why would I want this? I can use CrashPlan to backup my files to the 'cloud' safely. I don't care where it's stored, as long as it's safe. For fast access and high availability I could just buy a hard drive instead of a device that acts like a hard drive but instead stores other people's files on it.
If all you want are backups, then no, I don't imagine this is very compelling.
The idea is to actually access these files regularly from more than one computer. Hence the web interface and the emphasis on mobile devices. It could also serve as a media library for various devices, not just in your home, but presumably anywhere.
Dropbox and plenty of others basically do this already, but $10/mo at Dropbox only gets you 100GB. And I don't think it does streaming, though I could be wrong.
Personally, I'm curious how they access the files externally. The device must act as a server, I suppose, but it seems like firewalls would present an issue to less technical people. Maybe they just assume those people would never buy this?
The idea is to actually access these files regularly from more than one computer. Hence the web interface and the emphasis on mobile devices. It could also serve as a media library for various devices, not just in your home, but presumably anywhere.
Dropbox and plenty of others basically do this already, but $10/mo at Dropbox only gets you 100GB. And I don't think it does streaming, though I could be wrong.
Personally, I'm curious how they access the files externally. The device must act as a server, I suppose, but it seems like firewalls would present an issue to less technical people. Maybe they just assume those people would never buy this?
This option probably wins on cost and ease of use. For technically-minded people that can afford CrashPlan, though, this product may not be compelling; that's okay. Not all products are right for all people.
Really like the design. What I'd like to see is a device with a design like this that also has:
- options to pair up with specific other devices for the backups (family, trusted friends etc)
- a web app for posting status updates etc (implementing tent.io?)
Basically the things social networks offer now, but with you owning your own data.
- options to pair up with specific other devices for the backups (family, trusted friends etc)
- a web app for posting status updates etc (implementing tent.io?)
Basically the things social networks offer now, but with you owning your own data.
Why is this a subscription pricing model?.. if all the data is stored on peers Space Monkeys, then the only ongoing cost of keeping it running is electricity for the unit and bandwidth for the connection.
Unless it's a way to draw out more money over time from the user?
Unless it's a way to draw out more money over time from the user?
Yeah, Space Monkey is a business, and we hope to be able to make at least some money off the whole deal in the end.
But also yes, there are nontrivial ongoing costs to keeping the network working and working right. For example, we need dedicated online servers to allow NATted devices to talk to each other, coordinate storage use, and deploy security patches and bugfixes, and we want to add more features over time.
But also yes, there are nontrivial ongoing costs to keeping the network working and working right. For example, we need dedicated online servers to allow NATted devices to talk to each other, coordinate storage use, and deploy security patches and bugfixes, and we want to add more features over time.
So if I'm interacting with other users' devices, why am I paying $10/month?
This seems like a great (nay, genius) idea if you just buy a device that accepts a standard 3.5 inch HD, half the space is yours, half is for distributed backup, no monthly fees, just the upfront $ for the box itself..
This seems like a great (nay, genius) idea if you just buy a device that accepts a standard 3.5 inch HD, half the space is yours, half is for distributed backup, no monthly fees, just the upfront $ for the box itself..
While engineer in me loves edge distributed and duplicated shards of encrypted data, does the business model hold up against the economies of the giant cloud providers doing it all in a few of their data centers?
Sounds interesting, but I'd want to know what the estimates are for up/down bandwidth monthly. US data caps are common and tech like that could suck them up pretty quickly...
Both upload and download can be capped in the Preferences.
Upload, where bandwidth limits are the worst, is almost entirely based on replicating data you've added to Space Monkey.
(I have an alpha Space Monkey device.)
Upload, where bandwidth limits are the worst, is almost entirely based on replicating data you've added to Space Monkey.
(I have an alpha Space Monkey device.)
The early-bird option is already selling like hot cakes.
This is actually a really interesting device. I wonder how it works for a household though. Can there be different accounts setup per user?
It'd be nice if this was paired with BTC microtransactions for paying the owners of the devices that your blocks are on.
Does this use http://ceph.com/ ? Seems to take a similar approach.
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Does anyone know the Seagate device they used for their 'Alpha Test Network'?
Seagate Goflex Home. http://www.newegg.com/Product/Product.aspx?Item=N82E16822148...
Where is the encryption done and who has the keys?
How reliable is the network - will you be able to cope with Sandy style blackout?
Will there be a software component in which I designate a hard drive on my (always on) pc and skip the external device entirely?
How many times the data will be backuped?If only twice than if my home device get stolen/eaten by a rabbit/simply breaks then it is needed only one hardware failure somewhere else in the system to have stuff lost forever.
How reliable is the network - will you be able to cope with Sandy style blackout?
Will there be a software component in which I designate a hard drive on my (always on) pc and skip the external device entirely?
How many times the data will be backuped?If only twice than if my home device get stolen/eaten by a rabbit/simply breaks then it is needed only one hardware failure somewhere else in the system to have stuff lost forever.
The encryption is done on the device. Other people's devices (obviously) won't have your encryption key, but since Space Monkey will have a web interface to get at your files, you can tell that Space Monkey will have access to your key.
Regarding durability, the Kickstarter page mentions:
Regarding durability, the Kickstarter page mentions:
Q: Is my data safe?
A: Yes! Super safe. Here’s why: when you put files in
Space Monkey, you not only have a copy of everything on
your Space Monkey device, but each file is chopped up into
tiny pieces, encrypted, then stored to dozens of locations
outside of your home, in such a way that even if half of
those locations were destroyed, all your files would still
be safe.
I wonder if I may suggest the book:
_Normal Accidents_ by Charles Perrow
Please, please read this book RE: complex, tightly coupled systems.
_Normal Accidents_ by Charles Perrow
Please, please read this book RE: complex, tightly coupled systems.
tl;dr Space Monkey is a subscription-based Dropbox with a home NAS that replicates data offsite.
They require hardware/software/network engineering, manufacturing, support, sales, and more scaling to support these products.
I still don't understand how exactly they store all the data since this is supposed to be removing datacenter overhead, not adding to it. From what i've read it sounds like the home devices themselves are the redundant storage for all the other customers. Which sounds terrible.
They require hardware/software/network engineering, manufacturing, support, sales, and more scaling to support these products.
I still don't understand how exactly they store all the data since this is supposed to be removing datacenter overhead, not adding to it. From what i've read it sounds like the home devices themselves are the redundant storage for all the other customers. Which sounds terrible.
It doesn't just replicate data off-site, it duplicates and distributes your data to other spacemonkey users. It's like P2P cloud storage.
...Yeah, that's what I said. Still sounds bad, for three reasons: bandwidth, redundancy and availability.
Bandwidth is a simple consideration. In America we really haven't caught up to the bandwidth of most other 1st-world nations. Some reports give the average download speed of American broadband users at 7.1Mbps. Netflix reports the highest average broadband speed is with Google Fiber, at 3.45Mbps. Large swaths of the country still operate on 1.5Mbit connections or less, with upload caps being more like 256Kb for those users. Due to the disparity in speeds we can assume most of our transfers from home users would be limited to relatively slow speeds, not to mention (supposedly) using idle bandwidth.
If you need your files, how long is it going to take to get them? Assuming something like 2.5Mbps down, and if there were five copies of your data transferred at 256Kbps, that's 160KBps. Downloading at that speed would take 77.6 days to download the entire archive.
Then there's redundancy to consider. Disk drives are limited in capacity. Currently 4TB drives are available, with 5TB by the end of the year. To give each customer 1TB of storage while still storing other customer data on the device, you have to decide first how redundant you want the data.
If you have a fancy algorithm you can store hundreds of clients' data on the device. Maybe they only have a couple small files, so they can be replicated in lots of places in a small amount of space. But eventually the files will grow in size, so you'll have to remove some redundant copies to make room for maximum capacity. Let's assume they use something like RAID-6, because RAID-5 is shitty for large capacity small arrays. Since we assume a 4TB hard drive, we can have N-2 storage, so for 4TB that's 2TB; make it N-3 storage and you can fit 1TB of user data and 3TB of random customer parity.
With maximum capacity use, if three replicated copies of your data go away, your data goes away. How likely is this to happen? This[1] article explains how as drives increase in capacity they aren't increasing in reliability, which results in faster unrecoverable errors. As time goes by it's more likely your data will be lost.
This is assuming your data is available. If their software engineers are smart they might develop an algorithm that can take into account actual used space and add or shrink the number of replications across the network based on availability. So even if you have used 1TB of data, as long as other people have extra free space, you can keep replicating copies of your data to more devices. Sounds good!
Let's say your data is replicated on five devices. One device holding your data fails and is sent in for repair. Another is taken offline because the owner's internet connection is taken offline by a storm. Yet another is available, but is on a very slow connection. Your data is now on two devices. Sounds fine.
In the event that your device is unavailable, you will be able to replicate your 1TB from the two people who hold parity copies of your data. How much data that is, and how long it takes to recover, and whether or not that transfer puts one of their devices over the limit for a URE, is subject several factors.
Of course, there's many more factors to consider here, and i'm not an expert in any of them. But before you trust your data to a $10-a-month service, ask yourself: How reliable is the drive, how fast is the connection, and how much do you really need your data?
[1] http://www.zdnet.com/blog/storage/why-raid-6-stops-working-i...
Bandwidth is a simple consideration. In America we really haven't caught up to the bandwidth of most other 1st-world nations. Some reports give the average download speed of American broadband users at 7.1Mbps. Netflix reports the highest average broadband speed is with Google Fiber, at 3.45Mbps. Large swaths of the country still operate on 1.5Mbit connections or less, with upload caps being more like 256Kb for those users. Due to the disparity in speeds we can assume most of our transfers from home users would be limited to relatively slow speeds, not to mention (supposedly) using idle bandwidth.
If you need your files, how long is it going to take to get them? Assuming something like 2.5Mbps down, and if there were five copies of your data transferred at 256Kbps, that's 160KBps. Downloading at that speed would take 77.6 days to download the entire archive.
Then there's redundancy to consider. Disk drives are limited in capacity. Currently 4TB drives are available, with 5TB by the end of the year. To give each customer 1TB of storage while still storing other customer data on the device, you have to decide first how redundant you want the data.
If you have a fancy algorithm you can store hundreds of clients' data on the device. Maybe they only have a couple small files, so they can be replicated in lots of places in a small amount of space. But eventually the files will grow in size, so you'll have to remove some redundant copies to make room for maximum capacity. Let's assume they use something like RAID-6, because RAID-5 is shitty for large capacity small arrays. Since we assume a 4TB hard drive, we can have N-2 storage, so for 4TB that's 2TB; make it N-3 storage and you can fit 1TB of user data and 3TB of random customer parity.
With maximum capacity use, if three replicated copies of your data go away, your data goes away. How likely is this to happen? This[1] article explains how as drives increase in capacity they aren't increasing in reliability, which results in faster unrecoverable errors. As time goes by it's more likely your data will be lost.
This is assuming your data is available. If their software engineers are smart they might develop an algorithm that can take into account actual used space and add or shrink the number of replications across the network based on availability. So even if you have used 1TB of data, as long as other people have extra free space, you can keep replicating copies of your data to more devices. Sounds good!
Let's say your data is replicated on five devices. One device holding your data fails and is sent in for repair. Another is taken offline because the owner's internet connection is taken offline by a storm. Yet another is available, but is on a very slow connection. Your data is now on two devices. Sounds fine.
In the event that your device is unavailable, you will be able to replicate your 1TB from the two people who hold parity copies of your data. How much data that is, and how long it takes to recover, and whether or not that transfer puts one of their devices over the limit for a URE, is subject several factors.
Of course, there's many more factors to consider here, and i'm not an expert in any of them. But before you trust your data to a $10-a-month service, ask yourself: How reliable is the drive, how fast is the connection, and how much do you really need your data?
[1] http://www.zdnet.com/blog/storage/why-raid-6-stops-working-i...
1. Each node is paired with nodes that are "alike", and bandwidth is considered. You should only be paired with other nodes that have bandwidth similar to you.
2. Restoring backups takes a while. It's just the way it is. But the client should be smart enough to get prioritized data first -- if you need to open a picture, it should fetch that first, so you can open it right away.
3. Files are broken apart and stored in chunks, so "growing size of files" is irrelevant.
4. The probability of your data being lost doesn't increase over time. The node is constantly checking the status of your backups. If a chunk is missing over a long period of time, it will back it up again. Redundancy is only part of the solution -- some missing chunks are recoverable through erasure encoding (like in the article you mentioned). Your node backs up to hundreds of other nodes, reducing risk of failure. Think of having 200 drives in an array instead of 7.
5. The article is somewhat FUD. Making projections for 2019 based on hardware speed where we're at now? Many embedded devices are already replacing ARM processors with dual core intel. As data sizes increase, our processing power will also increase.
2. Restoring backups takes a while. It's just the way it is. But the client should be smart enough to get prioritized data first -- if you need to open a picture, it should fetch that first, so you can open it right away.
3. Files are broken apart and stored in chunks, so "growing size of files" is irrelevant.
4. The probability of your data being lost doesn't increase over time. The node is constantly checking the status of your backups. If a chunk is missing over a long period of time, it will back it up again. Redundancy is only part of the solution -- some missing chunks are recoverable through erasure encoding (like in the article you mentioned). Your node backs up to hundreds of other nodes, reducing risk of failure. Think of having 200 drives in an array instead of 7.
5. The article is somewhat FUD. Making projections for 2019 based on hardware speed where we're at now? Many embedded devices are already replacing ARM processors with dual core intel. As data sizes increase, our processing power will also increase.
1. That sounds like a good idea. "Should" and "like" are interesting terms to consider.
2. Restoring backups should not take over two months. That's just not the way it should be.
3. I was talking about using up all of your allocated 1TB, not the size of individual files.
4. I suck at math and can't wrap my head around erasure codes. But think of hundreds of nodes in recovery mode: peak i/o load, bandwidth pegging, resulting in poor performance, higher heat, more likely URE failure. Ever use a cloud server where the neighbors are using too much i/o? That's what will happen to you when your device is pegged by serving file chunks to neighbors. Even with really good load-balancing you have to eventually choose between lower availability or swamping a node.
5. The article is based on UREs not increasing with the size of disks, leading naturally to more errors sooner. As capacity increases and URE stays stagnant, the problem gets worse. The projection will change if UREs get less likely, but there's no sign that will happen in the near future.
2. Restoring backups should not take over two months. That's just not the way it should be.
3. I was talking about using up all of your allocated 1TB, not the size of individual files.
4. I suck at math and can't wrap my head around erasure codes. But think of hundreds of nodes in recovery mode: peak i/o load, bandwidth pegging, resulting in poor performance, higher heat, more likely URE failure. Ever use a cloud server where the neighbors are using too much i/o? That's what will happen to you when your device is pegged by serving file chunks to neighbors. Even with really good load-balancing you have to eventually choose between lower availability or swamping a node.
5. The article is based on UREs not increasing with the size of disks, leading naturally to more errors sooner. As capacity increases and URE stays stagnant, the problem gets worse. The projection will change if UREs get less likely, but there's no sign that will happen in the near future.
3. I think he was referring to aggregate file size (total amount stored) not a single file. If that's the case, his point still stands.
4. He was probably saying that, as the average age of the nodes in the network goes up, the chance of them failing goes up. Also, the duplication you say (hundreds of copies) is in direct opposition to usable space (hundreds of copies means you can only use 1/100 of the space on your node. Because of this, I don't think your files will ever be duplicated on the order of "hundreds", probably less than 10. Also, it's important to keep clear: My node will backup to hundreds of other nodes, but each individual file fragment will only be duplicated to 3 (or whatever) nodes. That smaller number is the important one that keeps getting discussed.
4. He was probably saying that, as the average age of the nodes in the network goes up, the chance of them failing goes up. Also, the duplication you say (hundreds of copies) is in direct opposition to usable space (hundreds of copies means you can only use 1/100 of the space on your node. Because of this, I don't think your files will ever be duplicated on the order of "hundreds", probably less than 10. Also, it's important to keep clear: My node will backup to hundreds of other nodes, but each individual file fragment will only be duplicated to 3 (or whatever) nodes. That smaller number is the important one that keeps getting discussed.
There won't be hundreds of copies. A device may back up data to hundreds of other devices in total, though.
Space Monkey data will be resilient to considerably more than 3 nodes failing.
Space Monkey data will be resilient to considerably more than 3 nodes failing.
Hundreds of devices storing small files on your one hard drive could be more iops than the device can handle. Does Space Monkey account for other users potentially killing the performance of a single device?
These are totally valid concerns. The average home internet upload cap, especially in the US, is not very generous. But the idea with Space Monkey is that most of your ongoing data access will be directly from your own device. If you're at home already, that will be especially fast. If not, it will be slower, but we're still able to watch movies in remote tests over a crappy home DSL uplink.
Other people's upload bandwidth only needs to come into play if your device isn't available: its hard drive breaks, it gets stolen, your house burns down, etc. In that case, yes, getting all of your data back probably will be slower than you want it to be, but you will get it all back.
Regarding redundancy, be assured that Space Monkey can provide much better numbers than RAID-6. We do assume that a decent percentage of devices will have poor network uptime, and we want your data to be available and redundant even in the face of that, even if the "fancy algorithms" take more processing power on the devices than we would need otherwise :).
Other people's upload bandwidth only needs to come into play if your device isn't available: its hard drive breaks, it gets stolen, your house burns down, etc. In that case, yes, getting all of your data back probably will be slower than you want it to be, but you will get it all back.
Regarding redundancy, be assured that Space Monkey can provide much better numbers than RAID-6. We do assume that a decent percentage of devices will have poor network uptime, and we want your data to be available and redundant even in the face of that, even if the "fancy algorithms" take more processing power on the devices than we would need otherwise :).