Nortel TDM vs CS1KE IP reliabilty???

[ABHC]

Has anyone else had reliability issues with the Nortel CS1KE? We finally bit the bullet and traded in our old 81's and 61's for the new fangled IP based system. We have had more service calls and issues with this new PBX in 6 months than 10 years with the old TDM switches. (Mainly with the security server...)

I don't necessarily think it is Avaya, I believe the IP systems are just not built for 24 hour operation centers.

 

[Johnthephoneguy]

Once ours are installed and turned up we have had few problems. A trunk card is the biggest headache in most of our sites (over 1500)

I do not think the CS1K is 100% as reliable as the 81c that I have grown to love, but it is probably at 95%.

JohnThePhoneGuy

"If I can't fix it, it's not broke!

 

[KCFLHRC]

It has a lot to do with who installed it.

 

[gwebster]

You could argue that an IP-based system is actually more reliable.

A TDM system typically has one physical/logical connection from the phone all the way the way back to the core (with exception possibly of two procesors) and all the way back out to another phone. A failure in any of those connections will take you out of service.

An IP-based system can be constructed with multiple levels of redundancy both within the data network and within the IP system itself. If any of those fail, the built-in failover mechanisms will maintain service.

One key to implementing an IP-based system is ensuring that your data network is properly configured to support high-quality/real-time voice communication.

The other key, as pointed out, is having your data/voice systems installed and maintained by resources who are fully competent on those technologies. An IP system is inherently different from a TDM system and requires different knowledge/training. ..and yes you are going to have to do more proactive patching and probably more frequent upgrades.

 

[KCFLHRC]

Or another way to look at is you could lose one ethernet switch and have your whole Call center out of service. I'm definitely a pro TDM guy but I have been around a long time. I have long thought having your computers and phones on the same network is a bad idea. Seems people have gotten more use to the idea of crappy voice quality with all the cell phones that are out there so when their IP phone all of a sudden gets garbled they don't mind it so much. 10 years ago if the call got a little static you were getting a trouble ticket. Now people say, oh well. Sign of the times I guess. But overall, I believe the Avaya/Nortel quality has gone to hell as has their support.

 

[janaya]

they way I look at VoIP is, we are going there whether we like it or not.

There is nothing more reliable then good 'ol fashioned copper TDM. You have to ask yourself how many times was your network down and how many times was your voice system down.

When you go voip its like they stated. It all depends who sets it up.

 

[oldestgeek]

I've found that many of the post-install problems were caused by the data network people. They change an IP address, route, VLAN, etc from a site thousands of miles away and your VoIP system bites the dust. Of course after it mysteriously starts working again "no one touched anything on the network".

 

[ABHC]

I appreciate everyone’s response. As stated by some of the responders, we have had Option x's for 11 years with few issues. Corp users needed a phone; you placed one on their desk and walked away.
Our operations centers are utility based and manned 24 hours a day. There were many hooks into the 81 and 61 like ICB's, custom built ring down systems, trader phone systems, satellite trunk banks for emergency trunking, etc..
With the TDM systems it was easy. With this IP based system, just getting an analog fax or modem line to work seems to be a challenge. Right now we are fighting modem bank issues. Analog line cards connected to modems do not like to traverse gateways to get to PRI outbound trunks. No problem if they are in the same gateway. Avaya acknowledges the issue but hasn't offered a solution.

To all you young IT managers out there that think you have just got to move to VOIP because that is the trend or the converged options are endless...........Don't, unless you have no choice or all you need is a phone and don't mind squeals or random garbled speech. The VOIP vendors don't advertise the flaws in their systems before they make the sale.

P.S. Not looking for a fight. Just my opinion ….so far.

ABHC

 

[allenmac]

We have multiple locations running CS1000E (HA, SA, and Co-Res) under a mix of system releases ranging from 5.0 to 7.5.

I find that if the systems are installed and configured correctly, and the data network is properly configured, then the systems are every bit as reliable as an Option-81.

A typical site in my enterprise has the following:

1. CS1000E core consisting of:
a. One or more Media Gateways.
b. One or more PRI cards for PSTN trunking.
c. IP phone sets - 2033 for conference rooms, 1140e in newer offices, 2004p2 in older offices.
e. One COTS signaling server (HP).
f. One CPPM signaling server.

2. AudioCodes MP-114, or MP-124 SIP analog terminal adapters for Analog dial tone (fax, modems, wall-phones).

We have our Primary UCM running NRS, and our Secondary UCM running alternate NRS located in separate locations.

We are upgrading all sites to 7.5 with Aura System and Session Manager in the next couple of months.

We have a CallPilot 1005r at our headquarters that provides centralized voice mail to all of our remote offices.

All sites are networked using SIP trunks over an MPLS network.

We monitor everything with NetIQ.

We use a provisioning server and DHCP options to assign all firmware settings, including Node and TN assigment for the 1140 sets, so that a user can take one out of the box, send me the MAC address, and plug the phone in and have it up and running with no further intervention.

In the last 5 years, we have replaced 1 signaling server and a Media Gateway. Both due to internal power supply failures.