IP phones quality not so great on the VPN end

[notShai]

hi,

we have location 1 with the IP Office unit and a netgear FVX538 fw 3.0.6-25 (to DSL with a satatic IP)

and location 2 with netgear FVX538 fw 3.0.6-25 (to cable modem with dynamic IP which we just looked up and entered into the router - it probably doesn't change often) and a 5610SWIP plugged in to the netgear.

i created a VPN tunnel between the two and i get full connectivity with the 5610SWIP between locations 1 and 2.

in location 2 there are 5 office workers which use their laptops to wirelessly connect to a simple linksys router (which i set to bridge mode) which is connected to the netgear the VPN is set on.

we get cranky voice quality sometimes and at other times its crystal clear.

is there a way to tweak the netgears to perform better?
is the extra internet traffic at location two affecting the voice quality?
is there a way to separate the two via vlans (would it make a difference for the voice quality, and is it even possible to setup a vlan on those phones? / routers?)

thank you

 

[amriddle01]

is there a way to tweak the netgears to perform better?"

Possibly, but I doubt this is the issue

"is the extra internet traffic at location two affecting the voice quality?"

Very likely to be the issue, but you can't do much about the traffic once it has left the Router

"is there a way to separate the two via vlans (would it make a difference for the voice quality, and is it even possible to setup a vlan on those phones? / routers?"

All the VLAN traffic would still be going down the same bottleneck/connection so that would have little effect. Best bet is to set the Routers to prioritise the Voice traffic if they are capable of doing so

ACS - IP Office Implement

"What the Crocodile Hat....was that?

 

[hairlessupportmonkey]

i think your "satatic" IP might be the issue

 

[tlpeter]

Yes they are capable but if the line is not good enough you still will have issues.
You need to have enough bandwidth and quality of service on it.


ACS IP Office
APSS IP Office
ACA - Implement IP Telephony -- ACA - Design IP Telephony
APSS UC
ACA - Voice Services Management


______________
Women and cats can do as they please and men and dogs should relax and get used to the idea!

 

[lcsavaya]

lol, i think tlpeter has the answer, its almost satanic

 

[notShai]

i see the logic in that but its a time warner business grade cable modem with

Download Speed: 8140 kbps (1017.5 KB/sec transfer rate)
Upload Speed: 893 kbps (111.6 KB/sec transfer rate)

is it not enough upload? i now a voice channel takes 100kb, and the office user mostly download and not upload.

(@hairlessupportmonkey funny "satatic" catch)

 

[hairlessupportmonkey]

the trouble is you cant guarantee where the packets go when they leave A before the get to B, they might route via P,Q,R,S,T first.

you need to gauge jitter, that will give you an indication of the quality of the line. this measures the time for packet reassembly from A to B. the more jitter the poorer the quality the connection is.

 

[TheSmash]

DSL + Voice = Fluctuating Voice Quality.

It is the nature of DSL and you can't change it. Either live with it or start digging deep into your pocket for MPLS etc...

Sorry if this is not what you wanted to hear.

 

[notShai]

no, this is great info.

one more -
is it _DSL_ which is crappy, or is cable broadband also unrelaible?


best tool for jitter test?

http://www.pingtest.net?

 

[amriddle01]

notShai, use the handset itself or System Status Appliction to view the jitter but also out of sequence packets and lost packets also play a part in causing voice quality issues over the net

ACS - IP Office Implement

"What the Crocodile Hat....was that?

 

[hairlessupportmonkey]

i would be inclined to go with an LLU based SDSL connection. LLUs tend to route traffic nicer with less contention.

Cable has a tendency to have high contention, so their load balancing will probably screw around with your VPN.

I use Easynet LLU products where ever possible, starting at their premium surestream, then SDSL, then ADSL depending on costs. but you are in the US, so you might want to have a look around.

try doing several different trace routes over a course of a day and see what changes.