Ask HN: Why isn't VoIP better? • Hacker News Board

Re: Ask HN: Why isn't VoIP better?

#41

Post by biokoda » Wed, Mar 01, 2017, 1:03 PM UTC

dijit wrote: post #12

I don't believe what you ask for can ever exist. "Clear, Distortion Free, Low-Latency. Pick any two" comes to mind. When you're doing voip you're doing so over UDP because TCP has far too much latency to be agreeable, but this means a lost packet will be a digital distortion. The nature of the internet is that packets get lost or arrive out of sequence- that's why TCP exists in the first place.

> When you're doing voip you're doing so over UDP because TCP has far too much latency to be agreeable,

Lots of wifis, corporate especially block all UDP traffic. Sometimes they even block all non http/https traffic. Apps like Skype or Biocoded will find a way to route the call, but that can sometimes mean it has to go over https!

Re: Ask HN: Why isn't VoIP better?

#42

Post by scandox » Wed, Mar 01, 2017, 1:03 PM UTC

samat wrote: post #34

Little trolling: so you say you have 1.6Gbps connection at home? Maybe your connection has some latency issues?

Yes sorry I'm a dufus about these things. The issue has been thoroughly gone into down below.

Mea culpa.

Re: Ask HN: Why isn't VoIP better?

#43

Post by bjourne » Wed, Mar 01, 2017, 1:04 PM UTC

I always thought that cellphone calls were routed over ip networks and were using exactly the same low-quality codecs "real" voip is using.

Re: Ask HN: Why isn't VoIP better?

#44

Post by raarts » Wed, Mar 01, 2017, 1:04 PM UTC

All quality problems would disappear if QoS would be implemented across the entire public internet. Your ears are so much more sensitive to small anomalies.

I've been deploying VoIP since 2003, both in the US and in Europe. In Europe it is easier to find cheap DSL with QoS applied, which allows laying in a separate circuit for VoIP only. In theses cases there are no complaints.

VoIP also works well on fiber. But as soon as one part of the network path travels the public internet all bets are off because there's no guarantee you packets aren't dropped because of traffic spikes.

Everybody who thinks the internet is stable in anyway is way off. Route flaps, packet loss, overloaded hops, last-mile problems happen all the time.

I could talk about this for hours.

Re: Ask HN: Why isn't VoIP better?

#45

Post by bsaunder » Wed, Mar 01, 2017, 1:04 PM UTC

FLUX-YOU wrote: post #32

bsaunder wrote: post #22

Earlier quoted context omitted.

Sorry to down vote, but that's completely the wrong vector. Its a network issue (of some sort - bandwidth, latency, throttling).

How are games and voice software targeted at gaming managing to make things so much more clear? If it's a network issue, it's likely unsalvageable because the network is just crap. We need to be using whatever those are using. It is usually crystal clear and people are easily understandable even during large gatherings (EVE Online battles). I'm the same as the OP, and what's worse, people talk 20 feet from the cisco…

If you're audio sounds great for a network game and crappy for a phone call (to the same person you are playing a game with), its because some one (your ISP, your VoIP software, the other parties ISP, or VoIP software, or any network hop in the middle), is intentionally choosing poor quality codecs for you to lower your bandwidth utilization.

I've heard directly of novice VoIP engineers unintentionally taking out corporate networks trying to "help" improve audio quality, by picking a higher quality codec. It worked great when they tested phone calls in the middle of the night maintenance window. It really sucked the next day when packets started colliding. Crappy sounding codecs sound a heck of a lot better than 50% packet loss.

Re: Ask HN: Why isn't VoIP better?

#46

Post by scandox » Wed, Mar 01, 2017, 1:05 PM UTC

feld wrote: post #33

scandox wrote: post #17

Earlier quoted context omitted.

So what you're saying is: VOIP will never match PSTN? Because that's the mood music I get from the sysadmins at work too.

VOIP is considerably better than PSTN if configured correctly. There's no comparison. Your sysadmins don't understand VOIP.

Their ignorance is always just slightly less than mine. Which is a sign of their intellectual "efficiency".

Re: Ask HN: Why isn't VoIP better?

#47

Post by criddell » Wed, Mar 01, 2017, 1:05 PM UTC

Skype used to be fantastic when you could establish a point-to-point call. Today, I think everything gets routed through Microsoft so they can provide access to law enforcement. Some days it's good, often it's pretty bad.

Re: Ask HN: Why isn't VoIP better?

#48

Post by jasonjayr » Wed, Mar 01, 2017, 1:09 PM UTC

slau wrote: post #36

bsaunder wrote: post #21

So VoIP can be better... at the expense of needing more bandwidth. During the session initialization the two VoIP endpoints handshake over which codecs will be used (kind of like the Accepts header in HTTP). Just like images, higher quality codecs tend to use more bandwidth (though like images its much more nuanced than that). Similarly like image formats there's different amounts of loss in the encoding/decoding of…

It really depends on which codec you're using. We had an implementation of G.711, which is not bad, but far from great. However, the license costs for implementing G.729 were so outrageous that my previous company simply couldn't afford it (or wouldn't). G.729 offers better call quality for the same bitrate, or similar call quality for much lower bitrate. Typically, G.711 would use ~64Kbps, whereas G.729 can achieve…

That licensing scheme is INSANE, especially since codecs like Opus exist, and do a much better job.

Once you touch the PSTN though, you're uLaw anyway. Why would you pay that much just for in-network voice quality?

Re: Ask HN: Why isn't VoIP better?

#49

Post by walterbell » Wed, Mar 01, 2017, 1:10 PM UTC

Have you tried Wire's audio? The creator of the SILK (Skype) and Opus codecs is on their engineering team.

http://opus-codec.org

http://app.wire.com

Re: Ask HN: Why isn't VoIP better?

#50

Post by bsaunder » Wed, Mar 01, 2017, 1:13 PM UTC

slau wrote: post #36

bsaunder wrote: post #21

So VoIP can be better... at the expense of needing more bandwidth. During the session initialization the two VoIP endpoints handshake over which codecs will be used (kind of like the Accepts header in HTTP). Just like images, higher quality codecs tend to use more bandwidth (though like images its much more nuanced than that). Similarly like image formats there's different amounts of loss in the encoding/decoding of…

It really depends on which codec you're using. We had an implementation of G.711, which is not bad, but far from great. However, the license costs for implementing G.729 were so outrageous that my previous company simply couldn't afford it (or wouldn't). G.729 offers better call quality for the same bitrate, or similar call quality for much lower bitrate. Typically, G.711 would use ~64Kbps, whereas G.729 can achieve…

Yes, codec licensing costs are one of the reasons people choose to not use the better codecs. Also, yes there is a CPU trade off as well.

The decision is more complicate with many trade offs. But in general, the OPs issues are either fundamental network ones or an intentional choice of one of his providers (typically for cost reasons - manifested in some manner).