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Ask HN: Why is there no P2P streaming protocol like BitTorrent?

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Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#181

Post by hinkley »

mihaic wrote: post #82
karel-3d wrote: post #80

Earlier quoted context omitted.

I am not convinced about the random order stuff. If most people will stream from the start then the start will be more seeded? So it's all good. And the order is requested by the client, and there are clients that go in the sequential order, like Deluge

The benefit of a random order is that it forces you to actually keep all the packets, which makes upload more likely. Streaming lets you get away with not storing the whole file, which makes bad actors more likely. And, sure, some BT clients can stream the data, but what the default is makes a huge difference.

People will shut off the moment they get the full file. The randomness means that the last packet is as likely to exist as the first.

Would you want to watch the beginning of something that didn’t have an ending? How frustrating would that be?

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#182

Post by hwpythonner »

I think the missing piece here is why we’d want P2P live streaming in the first place.

If the goal is to cut costs — like vendors trying to avoid AWS/CDN bills — that’s a very different problem than building for censorship resistance or resilience.

Without a clear “why,” the tradeoffs (latency, peer churn, unpredictable bandwidth) are hard to justify. Centralized infra is boring but reliable — and maybe that's good enough for 99% of use cases.

The interesting question is: what’s the niche where the pain is big enough to make P2P worth it?

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#183

Post by Calwestjobs »

_flux wrote: post #129
Calwestjobs wrote: post #104

you can install Qbittorrent client, after loading torrent file/magnet link, right click on that torrent and click on Download in sequential order. torrent PROTOCOL does not require to download random pieces, in random order. ONLY bittorrent, inc. COMPANY which releases "Utorrent" and "Bittorent" NAMED APPLICATIONS/PROGRAMS does not want legal trouble from media/music companies. Because STREAMING is other legal catego…

I believe there is actually a reason why you want to transfer random blobs instead of from the start: it is waste of resources when a node needs to upload the same block multiple times to the network, if it could be uploading different blocks. > if you need instant nanosecond delayed stream I believe nobody was suggesting that.

what chunk is transmitted when, is not important technically, (programatically, it is doable, i do not know how to call that properly)

it is ONLY important when you need to not have people (SWARM) finishing downloading of torrent then closing torrent client app and not sending data chunks to next person.

BUT everyone is saying it is stream and has to be instant showing of picture/video.

so i do not understand why all those people in other comments are caring about state of swarm if we do have thousands people watching and everybody is saying there are big amounts of people watching but still caring about swarm..

(swarm thing is important with normal use case of BitTorrent, irrelevant for streaming)

i understand what they are saying, they do not understand that they are saying nonsense.

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#184

Post by scott_w »

hinkley wrote: post #181
mihaic wrote: post #82

Earlier quoted context omitted.

The benefit of a random order is that it forces you to actually keep all the packets, which makes upload more likely. Streaming lets you get away with not storing the whole file, which makes bad actors more likely. And, sure, some BT clients can stream the data, but what the default is makes a huge difference.

People will shut off the moment they get the full file. The randomness means that the last packet is as likely to exist as the first. Would you want to watch the beginning of something that didn’t have an ending? How frustrating would that be?

> People will shut off the moment they get the full file.

Perhaps but the time spent downloading it is also time spent uploading some of the file, so there's still some benefit. By having it in random order, you more evenly distribute the people with access to different parts of the file.

With streaming, if everyone downloads the same blocks at the same time, "bad actors" can dump all data they already watched to save disk space, harming potential peers that are watching slightly behind.

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#185

Post by googlryas »

apitman wrote: post #168
PaulRobinson wrote: post #106

For a while, I was CTO of a company called Livestation [0], which as the Wikipedia article states, was "originally based on peer-to-peer technology acquired from Microsoft Research". This P2P stack was meant to allow for mass scaling of lowish latency video streaming, even in parts of the World with limited peer bandwidth to original content source servers. The VC-1 format got into a legal quagmire, as most video str…

You bring up a good point. It's interesting that YouTube at least doesn't do p2p for their non-DRM content.

Sounds like a recipe for dissatisfied users

"Why's my internet slow? Oh, YouTube is uploading a bunch of stuff to other people"

"How did I hit my bandwidth cap for the month already? Oh, youtube is..."

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#186

Post by apitman »

googlryas wrote: post #185
apitman wrote: post #168

Earlier quoted context omitted.

You bring up a good point. It's interesting that YouTube at least doesn't do p2p for their non-DRM content.

Sounds like a recipe for dissatisfied users "Why's my internet slow? Oh, YouTube is uploading a bunch of stuff to other people" "How did I hit my bandwidth cap for the month already? Oh, youtube is..."

Those problems are implementation specific

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#187

Post by bawolff »

arghwhat wrote: post #158
bavell wrote: post #155

Earlier quoted context omitted.

> First of all, BitTorrent clients do not download in random order or wait 5 minutes. They usually download the rarest block first, but can do whatever they want, whenever they want. The problem here is that BT works so well because the clients default to "good behavior" (prioritize rare pieces first) and discourages "bad behavior" (leeching/no upload). This tilts the balance on the whole enough to maintain the healt…

With streaming, the service provider is generally also controlling the clients, so they should be much better off when it comes to client behavior. In case of bring-your-own-client, the incentives are exactly the same: Clients would likely default to good behavior as network health equals user experience, and exactly like BitTorrent there will be neither punishment nor need for it if some clients disobey.

> exactly like BitTorrent there will be neither punishment nor need for it if some clients disobey.

"Punishment" (tit-for-tat algorithm) is one of the defining features of bit torrent, especially in comparison to what came before it.

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#188

Post by bawolff »

delusional wrote: post #95
bawolff wrote: post #62

Part of the reason bit torrent works really well is that the file is downloaded in random order. It lets everyone cooperate, while still being robust to bad peers, bad network connections, churn etc. If you want live high quality streaming, a lot of reasons bit torrent works so well goes away. Latency matters. In bit torrent if the peer goes away, no big deal, just try again in 5 minutes with another peer, you are do…

I don't think people are appreciating the nuance of what you're saying. Most of what you are saying isn't accurate for netflix style streaming, which would actually be more aptly called "video on demand", but is very applicable to "live streaming" in the sense of live sporting events or news broadcasts. Video-on-demand is perfectly implementable on top of BitTorrent. As you say, there are some latency pitfalls you'll…

I generally agree, but once you do that you lose most of the properties that make bit torrent so effective.

E.g. if you arrange the network into a tree like that, you need to make sure all nodes are matched appropriately in terms of bandwidth, latency, geography, number of connected nodes. Now you have to somehow the network topology stays good in face of churn and bad peers. Suddenly everything is complicated and not looking very p2p.

Maybe dufferent protocols are possible to manage that, but i think there is a reason why p2p protocols kind of didn't develop much beyond bit torrent.

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#189

Post by bawolff »

Calwestjobs wrote: post #120
bawolff wrote: post #87

Earlier quoted context omitted.

If we are talking about a live stream (and not a stream of a static file), having the start be more seeded is useless.

mpeg stream / TS filetype / DVB-T/C/S broadcast IS static file, all 3 is same format, this format deals with every point you made... download specs and educate yourself. same with streaming audio, chunk IS static file, so every phone call you made last 30 years is static file.

The issue is not how the bits are divided into packets (or "files") but how those packets are distributed/used.

Obviously at the end of the day its a string of bytes, like everything is, the difference i'm trying to get at is differences in how the data is used and requested.

Its more a social difference not a technical one.

Re: Ask HN: Why is there no P2P streaming protocol like BitTorrent?

#190

Post by bawolff »

Calwestjobs wrote: post #178
imtringued wrote: post #138

Earlier quoted context omitted.

The word "file" is doing a lot of heavy lifting here.

what is difference what kind of data chunk it is? 0 difference. or for university educated - he introduced file as a helpful abstraction, so i work with that abstraction, if you say it is not good abstraction then tell him. calling ts file a file is absolutely correct in any sense of word. just to be thorough. in philosophical debate we are having in computer science. ( yes toxic sarcasm ) that one post is more to th…

I'm using "static file" to mean something pre-recorded that even if users will view in order, they will likely start at different times, so different users will be viewing different parts of it.

In contrast to a live stream where everyone is viewing the same part at the same time, and once that part passes nobody is likely to view the old part ever again.

This makes a big difference in terms of network design.

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