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VOIP QoS router settings advice please?

I always get confused / use firewall / router rules so infrequently that I don't know  what the right way to set these things up.

Can you help?

I have a VOIP service using a Grandstream HT-502 V1.2A gadget.  The call quality isn't always good.  That device is plugged directly into one of the ports on an actiontec router (left over from when we had verizon fios, but now we have cable internet 15down / 5 up speed.

I have lots of other devices plugged into a gig network switch in the basement that might be using the internet at the same time as the calls?  That gig network switch has 1 cable going over to the actiontec also (so there's only 2 cables on the lan side of the router).

To improve call quality, that's a job for QoS, right?

The attached picture is what I did in the actiontec router.  The grandstream has the ip of

But then i thought, should this be on the Ethernet/Coax or  Broadband Connection (Ethernet/Coax) sections? Did I at least get outbound rather than inbound correct?

But that just gets the call out of the house with highest priority.  Once it's on the web, it's fighting with all kinds of data / can't prioritize it, right?

Does the VOIP provider have any bearing on the quality of the calls? Iwe are using VOIPO.com).  is there  a way to substantiate / test where the poor qiuality - dropped fractions of a second in the conversation, etc.  NO stuttering, max headroom type things.  Just a m ssing sound here and there.

And most pressing, we have a house alarm service that uses the VOIP line. I know - that's not as good as copper / POTS. but it was working OK for months.  now, they say their system is saying calls are coming in garbled / it calls 10s of times because they can't handshake.

I at least want to try to the QoS.  Or any other suggestions you have, short of getting a copper / pots line.

SBSBroadbandNetworkingVoice Over IPTelecommunications

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8/22/2022 - Mon

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2) the grandstream has a pots jack / pots phone plugged into it.  And then a cat5 connection / connects to the router.  it just gives a dial tone in a house setting. Not connected to / don't think it supports a VOIP phone.  SO i guess answer #1 of the 2 choices you list?

3) fitting?  not sure of that word : (

4) you sayu:  try setup QoS settings (Most probably the grandstream already does it...).  The grandstream?  It's the router that controls who gets access to the bandwidth, right?  not grandstream?

The piucture may help but tryi to set qos - that's what I did in the picture? Did I do it right?

SIP AGL was already disabled.

2) My assumtion now still hold ;-)

3) (i am not a native english speaker..., can you tell?),
I meant get a better match on traffic characteristics... VOIP needs a steady stream and is time critical, an FTP trans fer is bulk and can fill the gaps...).

4) It is the the Endpoint's responsibility to set the correct TOS bits in IP headers. It is the Routers responsibility to honour these requests.  (hence QoS is a framework of several layers & distributed responsibilities).
Now not all routers look at the TOS bits. Not all equipment set the right bits. In VOIP most traffic has the right TOS bits set.
In general there is no problem if there is abundant bandwidth...., when bandwidth is insufficient then you need prioritizing of  traffic.
Good the ALG was disabled.  (you can always test  if it help full or not).

Is the router capable of handling SIP traffic different (with priority?, some can and will setup all kinds of stuff to help VOIP).
Yes the picture looks good enough.

Now the bandwidht issue this is only for outgoing stuff.... For the incoming you also need to arrange there will be headroom.
So you should limit bandwidth control on the inside link to 14Mbs (You can only manage outgoing traffic, prioritizing won't help as you have 1Gbps there and only 15 on the outside...., so the artificial limit below the outside down bandwidth will leave a gap for the others.
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James Murphy

not a native english speaker!?  You're better at english as a 2nd (or more?) language than I am as a native.

And Kudos (compliments) on knowing more than 1 language. You are great at it.

Time for dumb joke.

What do you call someone that knows 3 languages?  .......Trilingual
What do you call someone that knows 2 languages?.......  bulingual
what do you call someone that knows 1 language?....... American.  Sad but true.

Way more complicated than I expected : )

Thanks for your help.  i  will take a shot at this later.

Also from another forum, someone gave me this link (posted for others might benefit in the future if they come to this question:


Your router can do traffic shaping. That can help a lot.

(There is a lot of info on the Linux Router Project.. (lartc.org) it's an old site, but basicly nothing changes since then....
http://lartc.org/wondershaper/   they built the wondershaper, and documented it's workings.
So it can serve as a backgrounder....

I said earlier:
So you should limit bandwidth control on the inside link to 14Mbs (You can only manage outgoing traffic, prioritizing won't help as you have 1Gbps there and only 15 on the outside...., so the artificial limit below the outside down bandwidth will leave a gap for the others.
 here i meant that a router can only control the order it sends traffic.  so limiting part of the bandwith on the inside would cause sending systems to eventualy hold back... leaving room for voip.  The margin of 1Mbps (15Mbps - 14Mbps) might be sufficient, maybe slightly more is needed to maintain enough headroom for bursts.