My VoIP experience on LTE

Report back - Day 24:

I've just been on the receiving end of our VoIP service. I got a call from home while at the office. While the voice on the other end is clear without a doubt, there is a slightly annoying "jitter". Sometimes the voice also sounds ever so slightly digitised. I haven't found this while using the phone at home, having only complained about "dulled" voice quality previously (the suggestion was to use uncompressed audio).

In any event, none of these are major gripes or deal breakers. I'm still a happy camper.
 
Report back - Day 26

Just quick feedback. Got another call from home. The jitter I mentioned previously was less noticeable. I've decided it's really not an issue and won't affect my decision to proceed.

I've started prepping all the info to port my Telkom 011 number to Switch Telecom. This is how it works:

Thank you for your email submission. We would certainly be able to port your
Telkom number to our network and allocate it to your account. In order to do
away with the existing number on the VoIP line we would need to reconfigure the
handset with the new telephone number that is being ported. So this change will
need to be co-ordinated when we are ready to go ahead with activating the port.

The paperwork that will need to be submitted to get this process started will
be:

- A letter addressed to Telkom requesting that the port telephone number
011xxxxxxx to Switch Telecom.
- Copy of the most recent account for telephone number 011xxxxxxx.

Once we have the paperwork in we will submit the port request and await
approval from Telkom. Once we have approval we will coordinate the
re-configuration of the handset and then once we are happy that this has
completed successfully, we will request written confirmation from you that we
are able to activate the port. Port activation requests received prior to 3pm
will complete between 5pm and 7pm, Monday to Friday.
Click to expand...

Edit: I've since used the A510 handsets outside. It wasn't necessary but I turned off Eco+ to see the usual signal bars. By the pool and braai area the signal remains full. At the top of my driveway the signal drops by one bar. This means that the Siemens A510 handsets have great signal indoors and outdoors. No need to worry there.
 
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Azimuth,

Thanx for all the info and updates.


Do you or anyone else know if you can port a VOIP (087) number from one provider to another?
 
AFAIK 087 numbers are not portable. I stand to be corrected. It's one of the downfalls of using 087.
 
Unfortunately ICASA has not amended the regulations to provide for porting of 087 numbers.

It's a pity as, technically, it would be trivial for providers to implement, using the exact same mechanism as for geographic porting. It literally just needs a couple of tiny amendments to the number porting regulations.

The only scenario that is slightly more complex to implement is 086 and 080 porting as those numbers are allocated by ICASA individually (rather than in blocks of 1,000 or 10,000 at a time), so there is no number block operator to act as the custodian. But 087 numbers are allocated in blocks, just like geographic numbers, so will be technically trivial to port as soon as ICASA wakes up and allows it.
 
Report back - Day 30:

This was for yesterday (Sunday). While making a national call, my wife experienced her first ever error connecting. She tried twice and gave up. Last night she tried again and got through no problem. One error (while two attempts were made I'm counting this as one error) in 30 days seems okay to me.
 
Report back - Day 32

I've just given Switch the authorisation to port my Telkom number. :) I'm happy overall and there are quite a few benefits to the service - one of which is parallel incoming and outgoing calls. We just used this for the first time today and it was pretty cool. Also we need not miss calls and have to return them - either my wife or I can catch a call on the other handset if one is already busy.

From 1 Jan - 15 Jan, we've had 113 outbound calls (6h47m47s) and 33 inbound (1h40h1s). The running total is sitting at R122.73 this very moment. Average call cost per day has moved up slightly to R8.18/day.

While giving the instruction to proceed with porting (managing two household numbers is a PITA), I was made aware by callers than in the last 2 days inbound calls often need to be made twice. The first call the line appears dead. The second attempt the call goes through. The ringtone is also quite weird - not sure if that will change after the port. I've logged a support ticket for the inbound call problem.

Happy days. :)

Edit: experiencing a bit of a dip in my LTE speeds but even so, parallel calls are perfect.

738560604.png
 
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Wow, Switch already replicated the issue reported above. It's something between them and Telkom. They've now logged a ticket with Telkom. Amazing support!
 
Report back - Day 34:

All my paperwork is in, I should be ported on Monday. :D
 
Report back - Day 37

I logged a support request this morning due to another case of call dropout. Basically 3s at most with some jitter before and after the dropout.

This was between my 011568 Switch number and a 011294 Telkom number. Switch came back with a report of very high latency (above 1000ms) and some packet loss. This seems to be because of a difference between TCP packets and UDP packets. I've never seen higher than 100ms with Speedtest but this uses TCP packets. VoIP uses UDP.

I'm going to fiddle with settings on my LTE router to see what can be done. I'm almost sure that traffic prioritisation is turned off.
 
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Report back - Day 40

My geographic number port has been somewhat delayed due to the electronic Telkom invoice I submitted as part of the paperwork. It doesn't have line item detail like the old hard copy invoices. I had to eventually login to the system and take screenshots of line items as they are not available as PDF downloads.

In other news, just as my port is about to come through, I am getting major push back on the home front. This is mostly due to local and regional family members bitching that that they can no longer make free calls to us. And the complaints are constant so I'm getting tired of it all....I may just pack it all up and port back to Telkom. Epic fail.

Edit: forgot to mention the updates on the latency issues. In the meanwhile I've switched LTE providers from Telkom Mobile to Afrihost (MTN) - till month-end only. Even with triple the upload, around 21Mbps, and < 50ms pings on Speedtest, I continue to get very high latency on the Switch reports. I also cannot prioritise VoIP/UDP packets on the B593 router. Boggles the mind how LTE doesn't excel at VoIP - then again, 3G could really be bad.
 
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Report back - Day 50:

My geographic number port went through on Day 48, two days ago. I now have my old fixed line number back. :)

This morning I'm having the worst speeds I've ever experienced on my LTE connection. Naturally this is messing up calls to some extent and we're getting heavy echoes.

This is what my speed tests look like - the Telkom Mobile LTE sectors / backhaul are broken! We had heavy, heavy rain yesterday and last night so maybe something on the tower is water logged....

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What's interesting to note is that VoIP is still viable, amazingly! Besides the heavy echo on voices, both sides can still hear each other and there isn't any noise.
 
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gmza said:
Wirelesswarrior: g.729a is a compressed audio codec. If you want 100% land-line call quality, you have to change to G.711 A-law (i.e. fully uncompressed audio). But it will consume 80kbit/s versus 24kbit/s and, if you're paying for data per GIG, then that's 874 minutes per GIG for G.711 A-law versus 2912 minutes per GIG for G.729a.
Click to expand...

Report back - Day 57:

I've just flicked the switch to try out uncompressed audio. Might as well try the full VoIP service offering to fairly make up my mind.

It would be interesting to note actual bandwidth used per month and compare compressed with uncompressed audio. @gmza: is there a way for me to do this?

I no longer have the 011 568 number attached to my account so cannot accurately reflect on costs last month. From what I remember, my monthly cost topped my old Telkom fixed line monthly cost.

Edit: I found the account, while inactive, is still attached to my profile.

Last month we made 235 calls with duration 17h49m8s with a total cost of R320.28. This means our daily cost rose to R10.33, up from R8.18 on Day 32.

For the inbound calls, we received 67 with a total duration of 3h54m24s.

So together with the R49.00 line rental, last months bill came to R369.28. Pretty much on par with our previous Telkom fixed line but that was a capped cost service, where this VoIP service is not...

So the bottom line is, for me at least, VoIP is not going to save me any money. The benefit is solely being detached from copper with no inbound surges to worry about.
 
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Report back - Day 58:

Our service is offline. Must have something to do with the codec change I made last night in the control panel. Bugger.

Edit: I fixed this myself by changing the codec back to the original one. Apparently one needs to request Switch to make the codec change.
 
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Report back - Day 65:

I have to say that I'm rather amazed that my VoIP service continues to work. Currently my Telkom LTE tower is broken and I have a ticket logged. For a week now I've been getting speeds of 50kBps down and 15kBps up. Edit: this ended up being a Ubiquiti network problem which I resolved on my own. It wasn't a "broken" tower issue. Shame on me for saying that.

Unrelated to the above, while I have Internet and data left, my service is down this morning. I've logged a ticket accordingly. SWT #25488

Edit: service outage affected everyone and not just me. There were ~ 3 hours down time.
 
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Report back - Day 87:

A couple weeks ago I requested that my service be configured to the G.711 A-law codec ie. pure uncompressed audio. I must say I've been pleased with the difference. Everything is much clearer and well worth the extra bandwidth used - 80kb/s vs 24kb/s.

*However*

My wife still complains weekly about call dropout and I just don't know what else can be done. She says that while on national calls the line will go dead for a few seconds at a time which causes annoyance on both ends. I tested this myself with a call to friend some 600km away. Over a period of 45m, I didn't have a single issue. It could be that things are simply worse during the day than at night which is a peak vs off-peak issue.

This certainly isn't due to my home LTE network. I've posted before about the horrible latencies for VoIP on LTE *despite* 30ms latency measured via Speedtest. I don't know if I can make this statement conclusively but LTE isn't great for VoIP. For home use it's perfectly fine but for business it won't be acceptable to your customers. Note I've tested both Telkom Mobile and MTN LTE networks with the same result.

On the billing front, my Month 3 bill was rather good. The total was R276.97 + R49.00 line rental = R325.97. This is around ~ R35.00 cheaper than what my monthly Telkom bill used to be. That's not a huge saving but it's nice to see some reduction in monthly expenditure. Over Feb 2014, 196 outbound calls were made with a total duration of 14h53h8s. We received 107 inbound calls with a total duration of 5h46m17s. The daily average cost of the service for Feb 2014 was R11.64.

For the record, Month 1 (Dec 2013) daily cost was R6.76 and Month 2 was R13.19.
 
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Just had an inbound call and I was thinking on the very same issue stated above: things seem perfectly fine after switching to uncompressed audio yet my wife maintains she has daily problems. Well, I just experienced it for myself although it wasn't call dropout. I experienced jitter so bad that the voice of the other person was like a strobe. This lasted for 5-10 seconds. I've reported it accordingly. SWT #26330
 
Packet loss concealment is optional for G.711. Personally I would never use G.711 for voice, because it sounds a muffled as a normal land-line telephone call to me.
I would rather add 20ms of latency by using a compressed full-band codec @ 64Kbit/s such as Opus, but this isn't possible without using custom software on a PC at the moment :)
 
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