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Ask HN: Why isn't VoIP better?

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

#31

Post by feld »

Both ends need to support wideband codecs, as does your phone (hard or soft phone). This includes the VOIP providers needing to be able to use wideband codecs between each other.

If you achieve a wideband setup the call quality is amazing. I've used it for years. It really sucks when you have to call someone on a legacy POTS line or using a narrow band codec (bad voip, cell phones, etc)

On that note it's unfortunate that cell phones which can do wideband codecs within the same carrier (HD Voice!) won't work if your call leaves their network.

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

#32

Post by FLUX-YOU »

bsaunder wrote: post #22
zamalek wrote: post #8

It's probably because most people have horrible quality microphones.

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 conference phones (because those are everywhere) and it makes everything sound completely terrible. I don't listen half the time. That is definitely a microphone issue.

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

#33

Post by feld »

scandox wrote: post #17
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.

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.

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

#35

Post by feld »

guan wrote: post #16
sheepdestroyer wrote: post #9

Earlier quoted context omitted.

Possibly OP was incorrectly confusing Mbps and MBps but in Japan Sony offers 2Gb/s for home connections. I had their 1Gb/s plan for ~6000JPY/Month when I was living in Kyoto. Was great

How is a 2 Gb/s home connection presented? 10GbE?

Yes

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

#36

Post by slau »

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 the same call quality for ~8Kbps (there's also a variable encoding that scales between 8 and 32Kbps). This being said, G.729 also requires a lot more CPU processing power.

If I'm not mistaken, each party of each leg of a call needs a license, which means that for a typical call centre with an IVR server between the agent and the customer, you need:

Summary:

- PSTN converter to IVR: 2 licenses / per customer

- IVR to agent: 2 licenses / per agent

- IVR to supervisor: 2 licenses / per supervisor.

It's pretty normal to see 300-agent call centres, and you typically want at least 300-900 calls waiting. Let's say there's between 10 and 30 supervisors.

300 * 2 + 900 * 2 + 30 * 2 = 2460 licenses. At $6-10 per license, that's more expensive than most hardware PBX solutions alone!

For IVR companies that handle multiple hundreds of thousands of calls per day, it's not really worth it.

Edit: Formatting

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

#37

Post by mikekchar »

Lots of good answers, but there is another one that's important too: echo cancellation. Most telco equipment has very good echo cancellation hardware in it. It's not impossible to do a decent job in VOIP, but not all of the software does it well. This can be very important when you have high latencies or if you are doing conference calls.

The other main overlooked problem is automatic gain control in software. This one drives me crazy. Most people are too lazy/clueless to set the gain properly on their microphone, so VOIP client makers tend to use automatic gain control to adjust the input. However, it works very differently that what you are used to in a telephone. If someone laughs loudly, or coughs you end up losing the beginning of the next sentence. It can work extremely badly in conjunction with echo cancellation depending on the software -- to the point where the audio can be very difficult to understand.

It's probably my biggest gripe with Google Hangouts because there is no consistent way to shut of AGC on all platforms.

I've written VOIP clients before and it is possible to have incredibly good audio (much better than normal PSTN -- mainly because the codecs are better). But it's very tricky to get it to work on random hardware, with random network conditions and with users who don't want to configure their client optimally.

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

#38

Post by sgt »

We have several VoIP lines on several locations. The quality is actually great. If you want guaranteed quality, use a dedicated voice VLAN or some sort of QoS.

Even in places where we don't have this in place, it seems to be working just fine for us. I can also say that I've used Skype to a PSTN in a separate continent over a slow mobile link and it also worked.

However: I have to mention that the quality is never quite as good as normal Skype (so called "HD" quality).

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

#39

Post by scandox »

MandieD wrote: post #27
scandox wrote: post #23

Earlier quoted context omitted.

At home I use Ethernet, a Blue Yeti USB microphone and a solid pair of Philips USB headphones. Of course I don't know what my counterparts on the other end are using. I guess my problem seems to be that we swapped a system that had a consistent call quality for one that is inconsistent, for a whole bunch of reasons. It seems to me, as if the general quality of telephony took a huge step backwards. And I don't underst…

Are the 1 in 3 good calls pretty random, or do they tend to be with the same counterparts? Do you notice a difference between the quality of your calls into conferences (if on the same platform) and direct calls with colleagues? WiFi can be a source of the problem even within the corporate network if the access points weren't designed for VoIP.

It seems random to me, but of course when I'm in User-mode I'm probably quite a poor observer.

I'm not a power user of VOIP, but these are my common scenarios:

1. At home, Skype and Google Hangouts. Hardware setup as above. 240 Mbps connection. Making calls to family abroad. This is the 1 in 3 scenario - we just keep trying till we get a connection that seems to work. Usually the call ends whenever the line finally "goes bad".

2. At work: Skype, Hangouts, Upwork. Mostly one to one calls with potential hires, colleagues, outsource people etc. WiFi. About a 20Mbps connection. Actually now I write it down Upwork is the best - which is weird because in general their systems suck. But Skype and Hangouts are both a consistent source of pain, dropped calls, bad quality, sudden total loss of audio etc...

3. At work: Company phones. Generally the quality is OK when calling out to landlines and mobiles (cell), but I have colleagues who I know are on VOIP at other end and these calls are like 1 in 2 where we just give up.

4. On mobile (4G): Viber, WhatsApp, Skype. Generally I'll call. Within a few seconds we'll be talking like people in a disco and I give up and call back on regular phone.

I also observe colleagues doing a lot of: "can you repeat that", "sorry repeat that" when they're using Skype at the office. Even hearing that contributes to my sense of VOIP-malaise.

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

#40

Post by kalleboo »

guan wrote: post #16
sheepdestroyer wrote: post #9

Earlier quoted context omitted.

Possibly OP was incorrectly confusing Mbps and MBps but in Japan Sony offers 2Gb/s for home connections. I had their 1Gb/s plan for ~6000JPY/Month when I was living in Kyoto. Was great

How is a 2 Gb/s home connection presented? 10GbE?

Looks like they now offer 10 Gbps. And yeah, it shows 10 GbE ethernet card support https://www.nuro.jp/10g/

edit: here's a list of their supported end-user equipment, they all seem to only have 1 Gbps RJ-45 ports https://www.nuro.jp/device.html

edit2: for the new 10 Gbps service they have self-branded routers with one 10GBASE-T port (and 3 gigabit ports), dunno what hardware it's based on https://www.nuro.jp/news/150601/10g_150601.pdf

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