Voice Quality Issues Over SCN 2

[fakename05]

I have a customer that has 4 locations that are all SCN linked over their WAN. There are 2-406v2 systems, 1-412 at the central location, and 1-500. All of the sites use digital sets except the location with the IP500--they use 5610 sets. They have Cisco routers and switches. Everything sounds great most of the time but occasionally the voice quality is degraded so much that they hang up and use cell phones when calling between sites. Their voicemail also sounds bad from time to time.

The method of prioritization that they are using is to give the traffic from the IP address of the phone systems and from the voicemail pc the highest priority. That is how their network guys have it set up and they are blaming the poor audio quality on the fact that the 412 uses half-duplex on the ethernet port.

A tier 3 engineer isn't being much help. He simply says that it looks like network problems but offers no suggestions to what I should have their network people change to make this better.

Any suggestions?? This customer is getting frustrated. (and so am I!) Thanks for any help anyone can offer.

 

[Belrick]

Hehe
Grab some phones, a lan cable and connect it between the IP412 and another IPO. Ask the customers network guy to duplicate the same fault that occurs over his network.

Feel free to bet some $$ with him that he can't.

Once point is conceeded feel free to walk away

 

[fakename05]

The customer just provided me with a report from his router that shows the following:

Hardware is Gigabit Ethernet Port, address is 0015.f9b2.9c84 (bia 0015.f9b2.9c84)
Description: Avaya_412_LBB
MTU 1500 bytes, BW 100000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Half-duplex, 100Mb/s
input flow-control is off, output flow-control is off
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters 6d17h
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 14000 bits/sec, 14 packets/sec
5 minute output rate 13000 bits/sec, 21 packets/sec
35163558 packets input, 4893715305 bytes, 0 no buffer
Received 403785 broadcasts (0 multicast)
5256 runts, 0 giants, 0 throttles
5256 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
40700147 packets output, 3879666254 bytes, 0 underruns
171176 output errors, 16659 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out



Isn't that a high number of output errors and collisions? Actually, they've had days with significantly more errors than this. What could be causing so many errors?

 

[ChristianF]

Change a port to monitor the IPO on one of their switches and run a wireshark trace to see if that gives you any more insight.
We never guarantee QoS between sites on SCN unless over a managed dedicated SDSL connection (or lease line etc).

 

[jamie77]

Have they set the Gigabit port the IPO is plugged into as 100MB Half duplex????

Is the bad voice quality from the IP Phones>Other sites or accross the board.

Tell them to use VLAN or DiffServ on the Ciscos for QOS and stop messing about. If they have only set priority on the IPO IP addresses, what about all those IP Phones?!?!?!?!?!?

What are the links between sites???

Jamie Green

ACA:Implement - IP Office
ACS:Implement - IP Office

http://www.alliedcom.co.uk

Football is not a matter of life and death-It is far more important!!!!

 

[mattKnight]

Jamie has hit the nail on the head

Agreed that 100mb Half duplex is not ideal, but it isn't the whole problem.

Did you do a network assessment prior to implementation?

Take Care

Matt
If at first you don't succeed, skydiving is not for you.

 

[fakename05]

Yes, a network assessment was done. Also, the customer has network monitoring equipment constantly running.

The gigabit port is set to 100Mb half-duplex.

Above is one of the reports from the Cisco switch. It seems to have a high number of collisions on the port that connects the IP412.

The IP phones sound good except when calling a digital phone across their WAN. The issue is across the board -- digital phones calling other digital phones across the SCN happens more simply because that's the vast majority of what users have and they have all of the same issues. However, problems seem to typically arise during busy times of the day. (both in terms of call volumes and data traffic)

A T-1 from each location goes back to the main site. It is set up as a MPLS network.

Could it be that we are only using a single LAN port into the customer's switch and the router is taking it from there? Do I need to set up a second port for calls across the WAN? If so, what other changes do I need to make in the IP Office?

Thanks again for all of your help.

 

[tlpeter]

If the call volume increase and the qualtity degreases then you have not enough bandwith
What codes is set for the ipphones and the iplines ?

Also there must be QOS setup otherwise it is useless to even try to solve it


ACA - Implement IP Office
ACS - Implement IP Office
ACA - Voice Services Management
______________
Women and cats can do as they please and men and dogs should relax and get used to the idea!

 

[fakename05]

Calls across the WAN are set to be G729.

I believe that that DiffServ matching has been set in the routers but I'll verify that.

 

[tlpeter]

I am not sure but i thought that Cisco uses slight different settings then the ipoffce
But again i am not sure, i am not familiar with Cisco !
You can find the settings of the ipoffice in the lan settings


ACA - Implement IP Office
ACS - Implement IP Office
ACA - Voice Services Management
______________
Women and cats can do as they please and men and dogs should relax and get used to the idea!

 

[fakename05]

tlpeter, you are correct about Cisco using different settings. I am pretty sure that the router settings were changed during installation.

The customer and Cisco network vendor keep pointing to the high number of collisions and errors on the port that supports the 412. Any ideas why there would be so many?

 

[tlpeter]

No idea


ACA - Implement IP Office
ACS - Implement IP Office
ACA - Voice Services Management
______________
Women and cats can do as they please and men and dogs should relax and get used to the idea!

 

[h382]

fakename,

like other have said you want to make sure the Cisco is using the same DiffServ value as the IP Office, the default is 46. If it is anything but that, you basically have no QoS going on.

As for the errors and collisions.. I'm not sure what would be causing that off the top of my head. We have a 412 plugged into a Cisco switch with SCN, digital/IP sets, MPLS network setup, etc with no issues except during peak hours. There is no QoS turned on at the provider yet, as this is a work in progress and the users don't even know about inter office dialing yet.

Who is the provider hosting your MPLS? Have their turned QoS on at their end?

 

[fakename05]

h382,

I'll have the customer check with AT&T. I'm pretty sure that is who has their circuits.

I'll report back what I learn. Thanks for the idea!

 

[kflounders]

Also verify that the signaling Diff serve setting is also set up. The IPOs sometimes ship with the diff serve at 0 instead of 34.

 

[l33byt1980]

I would be looking at the collisions part.

Any routing loops? Duplex mis matches within your network topology?

What routes do you have in the IP Office its self?

ACA - IPOffice implement
ACA - IP Telephony
CCNA - Passed at last

 

[fakename05]

I looked at the configs again. The Diffserv on the 412 is set to 31 and all the others are set to 46.

I'm going to make the changes tonight and see if that fixes it. I'll report back.

Thanks again for the help!

 

[fakename05]

Okay, I upgraded to 4.0.14 on all the systems and 4.0.27 on the voicemail. I changed the Diffserv on the 412 from 31 to 46. (like it should've been all along)

We're still getting warbling on the calls. From the site where voicemail is located I placed a call to a phone at a second site on the SCN. The business is closed so no one was at the desk and the call rolled back to voicemail. Even the ringing of the phone sounded broken and had skips. It's after-hours and there is virtually no traffic on the LAN or on the WAN.

The SolarNet monitoring software they are using shows that there are literally hundreds of errors on the 412's ethernet port throughout the day. What is the possibility that I simply have a bad 412?

 

[kflounders]

Try a constant ping to the LAN port on the 412. Does it fluctuate greatly?

 

[fakename05]

Do I need to do this after-hours?