Broadcast Distribution based on SageTV?

[tomfisk]

OK...I've been playing around with TV Tuners and SageTV, Placeshifter, and Media Extender. I am the president of a condo association and it occurs to me that we could use a sufficently big server with multiple tuner cards, hard drive space, and SageTV to provide broadcast distribution to our homeowners. We've had homeowners express discontent with the cable provider (mostly $$$ in a monopolistic environment). We looked into our own DishTV/DirectTV distrinbution about 3 years ago and we didn't get a lot of interest from the homeowners and the initial outlay was considerable for the infrastructure.

Now...with Sage and TV tuner cards things are looking a little different. I don't want to discuss the legal/social/political aspects of doing this, but rather the technical aspects. In installating and customizing Sage it looks like we could provide this as a "utility" to our homeowners, giving them their own "sandbox" to "SageTV" in (they only see the recordings they've made, not their neighbors, don't let them access Setup with a customized interface, etc). We have two Cat 5 lines into every unit from a utility room in each building (there are 5 buildings, 16 units in each) so putting up a 100mb network in each would be relatively easy. Benefits over cable is that there is the possibility of providing it cheaper, offer EPG & DVR capability, and throw in high speed internet access to boot. Homeowner's would have to purchase a media extender and any additional networking equipment for their unit. We would probably just offer extended basic service...HD and Digital cable would seem to be problematic at this point. We would offer each homeowner two tuners, one for DVR and one for live TV. It's not necessary that we get every homeowner to buy into this...but those that have extended basic already would be our target. There are going to be homeowner's who want to splurge on the digital/HD world already offered by cable and we would just let those continue to pay $$$ for their vegging activities.

So...is it possible? What kind of hardware would we need to provide enough capacity for 32 tuners? Is it possible to stream that many clients off one server? SageTV limitations you might see?

Is this pushing the envelope?

Thanks for your thoughts!

Tom

[lobosrul]

I saw another thread here about a school using Sage as a distribution service, but I think that was all (or almost all) standard def. I'd look up that thread if i was you (they were succesful).

Hardware wise, you will definantly want to go with dual-tuner hardware encoder cards (ie hauppage). Find a mobo with 8 PCI slots (if such a thing exists), and you have 32 tuners in two boxes. I think sage should be about to handle that. There are also USB tuners.

HDTV tuners, I dont think there are any hdd's that could handly having that many HDTV streams written to it at once. You would probably need multiple RAID arrays.

As far as sat. goes, your only way of doing this (for HDTV) is the r5000. And that costs around $550 for each box to be modded.

Cable, theres the firewire solution, but your cable co can enable 5c on any channel at any time. Also I cannot watch and record at the same time thru firewire for more than a few minutes (this might not be a universal issues however).

Distrubution wise, even if your using gigabit ethernet to get all this out there, theres no way your going to be able to do anywhere near 32 hd streams at once. Theoreticaly gigabit is plenty for 32 hd streams (each stream is a max of 19 mbps atleast OTA, but in practice usualy no more than 14mpbs). But take into account other traffic on the line (unless its not being used for internet), and the fact that ethernet is a time-split networking system. Only 1 packet at a time is over any given line (in a single direction). Multiple hd streams would lead to massive congestion.

Yes, i think SDTV alone would be possible. But if you dont have permission from the cable-co, and they catch you. Your probably looking at jail time.

Oh i just saw you mention 100mb LAN. Gigabit or bust for 32 tuners, especialy if theres also internet traffic.

[GKusnick]

Originally Posted by tomfisk

We would offer each homeowner two tuners, one for DVR and one for live TV.

Just to clear up a common misunderstanding: tuners aren't dedicated to specific clients. Two clients watching or recording the same program (it amounts to the same thing) do not need two different tuners to do it. Tuners are assigned by Sage per recording, not per client. So if you have 80 clients watching/recording a maximum of 20 different channels at once, you need only 20 tuners, not 80 (or 160).

It also sounds to me like you're going to need some extensive UI customizations if you want to hide each resident's Sage activities from other residents. This is certainly doable, but it's going to take a fair investment of time to create that custom UI and keep it current as new versions of SageTV are released.

As lobosrul said, very large systems of this sort have been discussed before in the Hardware section of the forum (where this thread will probably be moved by the mods). You should read through those threads for background before taking this idea any further.

SageTV in a school system
XXL Sage Install

[AndyS]

If you consider that each apartment will have at least two TVs, you have at least 160 clients to deal with. I just don't think that's a viable possibility, and certainly not at 100Mbps.

Even if you have a separate server for each building, that's still 32 clients or more per server, which is a stretch.

On top of the server cost you have client costs (MVP here I'd assume?) and ongoing support costs. You also need highly stable machines to run all this - you'll have a revolt if the TV system goes out!!


Perhaps you have a solution looking for a problem rather than the other way around? If you could help us to understand your reasoning behind wanting this solution perhaps we could offer some alternatives for you?

I'm not trying to shoot you down in flames - I just think that perhaps a reality-check is needed.....

Andy.

[GKusnick]

Originally Posted by AndyS

Even if you have a separate server for each building...

I was going to suggest this anyway. Bandwidth considerations aside, if a server goes down it's much better to have only 16 people ticked off at you instead of 80. Plus if the buildings are networked together, you can temporarily redirect users to another building's server while you work out the problems.

But Andy's right that there are going to be significant ongoing maintenances costs with a system this large, unless you have some competent tinkerers among your residents who are willing to take on sysop duties on a volunteer basis.

[stanger89]

A few comments....

HDTV tuners, I dont think there are any hdd's that could handly having that many HDTV streams written to it at once. You would probably need multiple RAID arrays.

HD runs between 1.5 and 2.5 MB/sec (<=19.4Mbps usually less these days), most drives these days are capable of upwards of 60MB/sec sustained sequential. Maybe 25-30MB/sec if it's pseudo-random, so that's enough for about 15 or so simultaneous HD streams.

SD is not that much different, our hardware encoders are not near as efficient as broadcast encoders, as such we see SD recording bitrates only about half that of HD, or in the 4-12Mbps (0.5-1.5MB/sec).

Either way, a single drive is probably not enough for order of 100 clients. RAID is nice, but actually, I might say JBOD is better since Sage's native disk usage strategy effectively load balances across drives.

Just to clear up a common misunderstanding: tuners aren't dedicated to specific clients. Two clients watching or recording the same program (it amounts to the same thing) do not need two different tuners to do it. Tuners are assigned by Sage per recording, not per client. So if you have 80 clients watching/recording a maximum of 20 different channels at once, you need only 20 tuners, not 80 (or 160).

To expand on this, this is what a lot of service providers do, that is they don't have enough resources for all customers to fully utilize their systems simultaneously, they have only enough for the "normal" amount of usage, since it basically never happens that all users are active at the same time.

So you probably wouldn't need two tuners per user, because it's almost inconcievable that every user would be using a tuner at the same time, and tuning a unique channel.

That would be an interesting thing to see, considering there's a high probability that there would be "clumps" of users recording/viewing the same program.

This would actually be kind of fun to lay out

It also sounds to me like you're going to need some extensive UI customizations if you want to hide each resident's Sage activities from other residents. This is certainly doable, but it's going to take a fair investment of time to create that custom UI and keep it current as new versions of SageTV are released.

I actually question if it really is doable. The primary roadblock I see is that from Sage, there's no way to tell what client added a favorite, etc.

To cut to the chase, I really don't think this is practical, especially if money is a concern, like it sounds like it is. Further, I don't see how this solves the problem, that being the cable provider, but anyway...

That said, given the current state of SageTV here's my best suggestion for a "successful" implimentation.

Most practical implimentation...
You'll need some sort of storage server, probably JBOD for the reasons mentioned above (Un-RAID maybe?). I was going to suggest you look into 10GbE, but that's more than 10x as expensive as GbE, so you'll probably want to look into mulitple GbE connections. You're looking at a PCI-X or PCIe based motherboard to support the kind of bandwidth you'll need to accomodate. Actually a single GbE is probably enough if you put a storage server in each building.

Connected to that via one or more GbE links (switch with load balancing?) would be several server machines (at least 2, maybe 16/building). These machines would house the tuners and run SageTV. There would be one copy of SageTV (server) running for each unit, and each SageTV instance would have 1 dual-tuner card (I don't know if mulitple copies of Sage can be run on one manchine and be associated with different cards).

Each server would be connected to the unit(s) that it feeds where there would be an MVP(s).

On the software side, the SageTVs should "share" the space even if you have it set to "use all", and thus you would hopefully be able to maintain the maximum storage for each user, but you may end up having to set Sage to "Use only xxx".

Like I said, the most practical, unfortunately it's little better than a SageTV system (ala VWB MediaReady) for/in each unit.

[stanger89]

Now, what could, theoretically be done, but would require significant customization and/or core changes, which are highlighted in blue, which is appropriate for the blue-sky nature of much of this.

The basic hardware setup would be quite similar, large fast powerfull storage server with multple JBOD (Un-RAID-type) storage, and several GbE links to a load balancing switch, from where the clients would be connected. In addition, you would have several encoding servers, as many as needed to accomidate the required number of tuners (less than 2 per unit, see below), these would be GbE connected directly to multiple GbE nics in the main SageTV/Storage server.

There will be one copy of SageTV that manages all the units. Each client has a unique ID that you would delegate on a unit-by-unit basis. The client UI would be much simplified, removing all the storage/tuner/STV/etc control interfaces, you don't want the users to be able to reconfigure tuners or storage usage.

You would setup some sort of database of which client IDs belong to which units, so that you could group the clients together by unit, and so that a given unit would have a consistent list of recordings and such.

This database would also maintain which favorites and manual recordings belong to which unit, so that when the user browses recorings or favores, they will only see the recordings/favorites that they have setup. Favorite priorities would need to be disabled from the user, or there would need to be a way to manage favorite priorities across different users with different assigned priorities. This could be a customization, if the server were to somehow take an average of the various client's desired priority to fit it into the master priority scale. Intelligent recording would need to be disabled.

When a favorite/manual is added Sage would need to check if that favorite exists, and if so add the unit to it's users, or if not, add the favorite, and likewise on remove, see if any other units are using it, if so, only remove the unit from users, and remove it entirely if there are no other users.

Watched status and deletion would again, have to be handled in the new database, keeping track of which units have watched a show and not setting the Sage watched status until all units have watched the show. Likewise for deletions, they would have to be removed from the unit's view, but not from Sage if any other units have not deleted it. There could be core changes required because watched status is handled in the core, and it would be difficult, at least, to get around that.

That would be a very cool setup, and pretty efficient given Sage's "intelligence" it would be far better than the more practical one, recording only one copy of a show, using the minimum number of tuners, and storage. But would basically require a whole new UI, and also either a massive core change to support multiple users, or a massive customization effort to maintain a database of users, and basically, to put an abstraction layer inbetween the Sage core and the Sage UI to deal with it.

[lobosrul]

Hmm, I'd suggest having one massive file server, and use (hardware) RAID-5. JDOB has no fault tolerance. 8 port cards are now reasonably inexpensive, as are 400GB drives. So you can easily put together 2.8 TB of hard drive space. However, as Stanger said, everyone will be able to see everyone elses recordings. Sage (atleast SageMC), allows you to organize TV recording alphabeticaly so it wouldnt be too hard for someone to find the show they wanted.

Also, if your going to go with say 32 tuners, simply make available the 32 most watched channels. Hell, I have like 300 channels, and in reaility i watch maybe 20, tops (but then Im an HDTV junkie). They wont need the Pre-vu channel, no one watches public access or the HSN, or animal planet (ok maybe someone does). Actualy I bet 40 channels would probably be safe for 32 tuners.

Having one Sage server per client, would be unreasonably expensive. For one you need 1 $80 license for each client, plus atleast 600-700 on hardware, oh and a copy of windoze.

EDIT: I wrote this before reading Stanger's 2nd post. I think he's having fun with this . On further thought, you will need a networking guru to even think about 160 working clients. A few 24 port switches, just wont be enough.

[stanger89]

Originally Posted by lobosrul

Hmm, I'd suggest having one massive file server, and use (hardware) RAID-5.

Normally I'd say RAID-5, but this is a sort of weird situation, in which it would seem advantageous to spread the load and accessing independently across disks.

JDOB has no fault tolerance.

That's why I mentioned Un-RAID, it's basically JBOD with redundancy.

EDIT: I wrote this before reading Stanger's 2nd post. I think he's having fun with this .

Well I was trying to figure out how to do it, and while I was thinking about what was possible, I couldn't help but try and think of the best way to do it

[lobosrul]

Stanger are you sure Sage somehow writes to multiple disks inteligently if your setup for JDOB? I thought the OS took care of that in a software implementation. And in a hardware setup the card should handle load balancing.

I've never heard of un-raid so I didnt know what you were refering to.

My primary Sage partition is 2 400GB disks in a JDOB array (xp pro software). But I did it for convenience rather than write performance.

[AndyS]

What's to stop someone installing SageClient on their own machine and thus gaining full admin access to everything?

Andy.

[lobosrul]

Hmm, can you set a password for sage clients, like the placeshifter?

I have 0 experience with clients, but I do have a placeshifter license.

[mayamaniac]

SageTV is not designed for multiple users with multiple preferences in terms of unique favorites/scheduling, viewing histories, access to recordings, etc. So if having each unit with unique settings is important, meaning that they don't see each others data, then I think this is the biggest hurdle to overcome, if its even possible. SageTV is not designed for this and I don't think it will work out.

Maybe when SageTV grows into a bigger company, they'll release SageTV Distribution Edition.

[GKusnick]

I think a fair amount of individualization is probably possible, along the lines of what Stanger proposed (which is more or less what I had in mind). However I wonder if it's really necessary. Maybe the right way to think of this is simply as a big shared TV-on-demand system, with all the popular programs scheduled for regular recording, so nobody has to miss an episode of Lost because they're working late that night. Which programs get recorded would be decided by community consensus, and all the recorded programs would appear in one big list that everybody sees. Anybody with additional viewing preferences they don't want their neighbors to know about can satisfy those urges the old-fashioned way, by individual cable or satellite subscription.

[lobosrul]

Thats how I was thinking GK.

But, the problem is, it wouldnt be community consensus. If even one person decided to record a show, its recorded.

This means some juvenile type could set everything to record on every single channel. Even a large disk array is going to be filled up quite quickly with 30 channels recording 24/7. This means that episode of Lost that everyone wanted to see will be gone quite quickly.

[SHS]

lobosrul part of what you want will not work becuases SageTV it self is not designed for multiple users with multiple preferences profile, favorites, scheduling, viewing histories will all be major problem becaes every thing stored on server side which also share with other SageTV Client.
Networking should not be much of a problem.

[GKusnick]

Originally Posted by lobosrul

But, the problem is, it wouldnt be community consensus. If even one person decided to record a show, its recorded.

Obviously you'd still need a custom STV for the extenders with those features removed, so that only server admins can alter the favorites list and recording schedule. But taking away features from the standard STV is fairly easy.

Originally Posted by AndyS

What's to stop someone installing SageClient on their own machine and thus gaining full admin access to everything?

I haven't tried it, but it looks like SageTVClient uses different ports than Placeshifter and MVP, so it's probably possible to firewall against Client access while still letting MVP and Placeshifter connections through.

[stanger89]

Originally Posted by lobosrul

Stanger are you sure Sage somehow writes to multiple disks inteligently if your setup for JDOB? I thought the OS took care of that in a software implementation. And in a hardware setup the card should handle load balancing.

Not 100%, but JBOD is just many individual volumes, and Sage writes to the one with the most free space. So theoretically at least, that should varry relatively evenly across drives and Sage would write to drives somewhat randomly.

My primary Sage partition is 2 400GB disks in a JDOB array (xp pro software). But I did it for convenience rather than write performance.

I think you're confusing JBOD with spanning. I'm not talking about a single volume across multiple drives. You're right with spanning, the OS takes care of where the files go on the drive. But with a JBOD setup of, say 8 drives. Theoretically if you had several tuners going, Sage would be writing to different drives most of the time.

What's to stop someone installing SageClient on their own machine and thus gaining full admin access to everything?

I can think of a couple ways, firstly being turning off server discovery (or disable the server from responding to discovery requests). Another would be mac address filtering on a firewall on the server, etc.

Maybe the right way to think of this is simply as a big shared TV-on-demand system, with all the popular programs scheduled for regular recording, so nobody has to miss an episode of Lost because they're working late that night. Which programs get recorded would be decided by community consensus, and all the recorded programs would appear in one big list that everybody sees.

That would be fine on the recording front, but the playback/deletion/cleanup front is where that becomes troublesome. By default, Sage will probably delete a show after one client watches it (when it needs space). How do you ensure it's retained for everyone to see? You could set do-not-delete, but then who's responibility is it to delete them. How do you keep others from deleting them, etc.

It could be done, but it would take a massive effort to basically "wrap" the core Sage functionality with a multi-user wrapper. The extensibility of Sage makes that possible, but it would not be simple.

[GKusnick]

Originally Posted by stanger89

You could set do-not-delete, but then who's responibility is it to delete them. How do you keep others from deleting them, etc.

I had something real simple in mind, like turning off auto-delete in Sage and then setting up a batch script that runs nightly and deletes everything more than, say, a month old. Users have that long to watch those back episodes of Lost and then they're gone. You prevent users from manually deleting recordings before then by removing the Delete command from the STV.

Of course nothing can save you if someone determined to do damage gains access to the server room. But I don't think it needs to be absolutely bulletproof. It just needs to be sufficiently idiot-proof so that some bored kid fooling around with the remote doesn't accidentally screw things up.

[lobosrul]

Originally Posted by stanger89

I think you're confusing JBOD with spanning. I'm not talking about a single volume across multiple drives. You're right with spanning, the OS takes care of where the files go on the drive. But with a JBOD setup of, say 8 drives. Theoretically if you had several tuners going, Sage would be writing to different drives most of the time.

JBOD(Just a Bunch Of Disks) is spanning. Or possibly you could say it is a hardware implementation of spanning.

http://www.pcguide.com/ref/hdd/perf/...ls/jbod-c.html