Option 11C VoIP Issues

[skymax]

I am hoping someone out there can supply me with some information and insight into issues I am researching on our Meridian Option 11C. What I am seeing or need is as follows:

1) I need to know how to print the current configuration in the Option 11C. My prior support vendor did not perform this function as asked. Guess that's why they are a prior support vendor.

2) I have 11 remote sites using i2004 phones. About 80 i2004 phones all together. One day they are all working - the next a few drop out - then the next day more drop out - then they all come back. When they drop out, they can converse from one VoIP phone to another. They can not access voice-mail or outside parties without encountering one way conversations.

3) Network is an ATM with Cisco 2616s in the field and an 3745 at the Central Office. I have BPS2000s installed in most remote sites. Others have Cisco switches. Phones and PCs are separated out into two VLANS via IP addresses. IP addresses in most phones are static. I have changed a few to use DHCP to see if it made a difference. Nope.

4) The PBX has two ITG cards installed. Viewing traffic, I see one card is handling more traffic than the other. I was wondering if there is a way to determine which phones are being handled by which ITG card.

5) How do I get a listing from the PBX showing extensions and the TN number associated with that extension?

6) I guess I am starting the process to maintain this PBX myself. Suggestions on which manuals or books to study would be greatly appreciated.

Thank You in advance.

Tim

 

[senk1s]

ld 22, issp and slt will give you sw rel and capacities

is there congestion or outages in the link to the remote sites?
do you have systems (11c or otherwise) in the remote offices

ld 81 for station print

admin guides and feature guides for ur sw release (downloadable from nt website with free registration)

 

[phonezilla]

If a phone is "dropping out" but it still can call from one IP set to another - then your problem is most likely a lack of DSP resources - your ITG cards ( depends on the s/w version of your switch) have a maximum of 24 or 32 DSPs -

A DSP is used to go from IP to TDM or vice versa PSTN TRUNKS , PRI TRUNKS , POTS LINES , DIGITAL SETS , ANALOG SETS, and VOICEMAIL PORTS are all TDM devices and would require the use of a DSP channel on the ITG card to complete a call from or to the device

If you have 80 phones and 2 ITG cards then you do not have enough DSP resources to gurantee a DSP for every IP phone.
If 20 IP phones were talking to each other the other 60 phones would compete for the 64 or so DSPs you have.

PhoneZilla

 

[skymax]

First, let me THANK each of YOU for replying to my post. I will answer questions you had concerning my situation and ask a couple of more.

1. We have not experienced any outages. We looked at this first and the logs in the UPS and routers do not show any power or network outages.

2. We have had three network assessments showing no congestion on the network.

3. Curious to how may ITG cards an Option 11C can support. Maybe a better question is the capacity of an Option 11c is?

4. I entered LD 22 on the main console. It accepted the command but did not produce a report. Was I not holding my mouth right or what?

5. Curious how to best reboot the Option 11C.

6. I believe I know which cards are my two ITG cards, but would appreciate a note from you on how to determine which card is which.

7. Do you have an URL directing me to documentation on the capacity of a ITG card?

Thanks

-Tim

 

[skymax]

I thought I would post a development that occurred today. After reading about the ITG card, I contacted our new support company. They looked into the situation of the two ITG cards and state:

1. Both cards are on the most current release.
2. The original card will handle only 24 DSPs.
3. The newer card will handle 32 DSPs.
4. That each DSP can handle 4 VoIP phones.

Therefore, according to them, I have 128 DSPs and should not have a concern about whether I have enough ITG cards or not.

I also was told I have paid for 121 licenses which should more than cover the 80 or so phones I have in the field.

I would really appreciate it if someone would let me know whether or not what I was told is correct or not.

Thanks

-Tim

 

[I2007]

What you really need to do is to look at your software level on the ITG cards, and what sw the opt11c is running. What I know is that some of the old ITG software had some problems under high traffic causing the ITG card to reboot, so your problem could be that. When a card reboots you loose a lot of DSP resources (24 or 32), and when 2 i2004 is conversating with each other it's not using DSP resources. You also need to be sure that the ITG cards (I assume it's programmed as a leader0 and leader1) has the same sw level and that the ITG cards has all the available patches installed as well as the opt11. It's remarkable how much a patch from nortel or sw upgrade can do when you have absolutely no idea of whats causing trouble.

FYI Nortel's advice is a ratio 4:1 between DSP and i2004 phones. So if you have 4 DSP's you can have 16 i2004 phones. But this depends on how much you really use the ip phones to call to other resources than between i2004's. 1 DSP = 1 voice channel. I have 64 DSP's on a system with 500 ip phones, the customer is happy and haven't complained at all.

i2007