Question: Cisco vs.Nortel 14

[WarbleKing]

I just got finished reading thread851-1343370 from the Cisco forum. We are debating the issue as well, however the main thing we are looking to deploy is SIP handsets. Our PBX is a CS1000M rls 4.5 that we are waiting to upgrade until a final decision is made. The above thread does not go into SIP that much. We are a standalone site with many buildings networked together but we do not have any IP trunking involved(yet). So I guess what I am trying to say is there a benefit from one system over the other, especially at the network level? Opinions about hardware, administration, costs, reliability, QOS, QOE and maintanence would be greatly appriciated as well. I would like to stay with the Nortel, because I have 14 years invested, but want to have the best solution in place. Our Network guys are pretty sharp and the majority of the network infrastructure is Cisco(with a few HP devices here and there). Thank you for the input, and I apologize if this is the incorrect place to post this, I am a newbie to this site.

 

[steve64]

Oh NastyNed2 mentioned analog. I don't know what CISCO was thinking but their analog interface is not bell compliant when it comes to ringing voltages. if you have 2500 or 2554 sets better plan on replacing them all as the CISCO wil not ring them!

 

[WarbleKing]

Great info, podcast was good also. We are rls 4.5 and have the SRS with Nortel and can go to 5.0, so I am assuming we are E911 capable. We are already have it down to the desktop for each extension, but we have to manually enter the info into PS/ALI. I will definitely pull out the features guide on Monday.

1.What does the E911 do without the LIS part? Basic OSN?

2. Do the zones correlate to the zones used on the ip phones(max 255)? If not, what are the max # of zones?

3. It sounds almost like a DHCP server, if the IP's are mapped to a zone in the northwest corner and a phone moves to the southwest corner, a new IP is assigned according to the subnet assignment to that zone, does the new IP assignment happen from the Nortel side, or is it somehow integrated to a DHCP server?

4. Do you know anything about RedSky? Can we upload from and download to the PS/ALI database since we already have the info?

Cisco is telling us there stuff can do the same thing as the LIS package, but we will have to buy a $7K server (can't remeber if the software costs us or not, Im sure it will!!!). However I do not think that we can break down out subnets that small, a lot of work for the network guys, and may be to difficult with our wireless networks. They have already assigned wall port numbers in the cisco devices, but the HP switches are not capable of that. The eTelemetry solution is something I might want to look at, especially since we have a mixed network infrastructure. If you have any insight on that, that would be great.

From what it sounds like the Nortel and Cisco offers pretty much the same thing, but we would be paying a lot more for the Cisco solution. A cost analysis is probably something we will need to really start to put together.

Im sure I have more questions, I will look some more at the websites you directed me to and post any more questions later.

Thank you again for everybodys input!!!

 

[steve64]

Bottom line is no matter how you look at it the Nortel solution is less expensive and far more robust than CISCO. It also still allows a mix of the TDM sets and analog with the IP. If I were putting in a new system I would look at Mitel before I even considered CISCO.

 

[911guru]

1.What does the E911 do without the LIS part? Basic OSN?

Without LIS you loose automatic location updates for IP sets. TDM is never auto located. You get all the other functions of ESA in 5.00 which is far more than 4.50 had. The concept of ERLs (E911 zones) applies to ALL devices on the system.

2. Do the zones correlate to the zones used on the IP phones(max 255)? If not, what are the max # of zones?

Bandwidth Zones remain in 5.00, but any zones that had ZESA defined automatically create ERLs and any phones assigned to those zones are moved to the ERL. They maintain their previous zones settings for BW management though. ZESA does not exist in 5.00, it is handled by the ERL function.

3. It sounds almost like a DHCP server, if the IP's are mapped to a zone in the northwest corner and a phone moves to the southwest corner, a new IP is assigned according to the subnet assignment to that zone, does the new IP assignment happen from the Nortel side, or is it somehow integrated to a DHCP server?

It's both, the PBX has a subnet map that assigns subnets and masks to ERLs. You don't have to dedicate an entire subnet to an ERL. You can define the appropriate mask with it. So a subnet of 192.168.30.113 with a mask of 255.255.255.248 would give you the .114, .115, .116, and .118 in that subnet. A mask of 255.255.255.0 would give you the whole class C range. You map scopes out in your DHCP server, and tell the PBX what that scope mapping is. Nice thing is once the scopes and ERLs are defined, your done! Everything auto updates and phones are assigned to ERLs as soon as they register with the PBX.

4. Do you know anything about RedSky? Can we upload from and download to the PS/ALI database since we already have the info?

Yup RedSky is the Cadillac. It does all the mapping you want and then talks to the PBX to assign the ERLs. You don't need the Nortel LIS function for this, since location discovery is done by RedSky. RedSky then updates the PS-ALI database for you every night, or when you want it to, and when the PS-ALI record goes live in a day or so, the screen pop is accurate at the PSAP. The vulnerability is then limited to the time between the station moves and the time PS-ALI is LIVE (not your update, but the back end processing at the LEC) to the dispatchers. You have to remember there is a lag there of a day or more!


Fletch has eTelemetry installed at his lab and has worked with them on the development of their Locate E911 product. REALLY SLICK! Nice little server appliance for under $10K, and it walks all your switch ports on the network and updates the PBX ERLs like the RedSky. Fletch told me they were going in for formal lab testing later this month so they could get their Compatibility Certificates for 5.00 and 5.50.

This also doesn't need the Nortel LIS since it is doing the discovery process. The only thing it doesn't do is PS-ALI updates, but in my opinion that's fine because you can go with the ERL zone approach and you are not limited to subnets since this is looking at switch ports on the data network. You can have a completely flat network in the building and just build their table of switch port to ERL mappings.

Fletch said RedSky and eTelemetry are both great solutions, and the difference is cost and functionality. RedSky is expensive, but it does it soup to nuts including PS-ALI updates. If you do zones, you don;t need PS-ALI updates, so the eTelemetry functions are more than enough and you save a huge amount of money. It all comes down to what you need. With a mixed data network, Cisco will ONLY be able to do IP subnets in CER. They can't walk non Cisco switches for phone information since CER relies on the proprietary CDP protocol for set discovery.

I consult for a lot of folks, and have played with most of the solutions out there. E911 has got me booked for the next 6 months, and I am only taking on Nortel work in the future. The other stuff is a pain in the backside, doesn't work as well, and is a bear to set-up. The Nortel stuff goes in quick and easy and I can concentrate my consulting time on developing the solution and operational controls companies need to put in place for MACs. I have worked on a ton of stuff, but have always loved the Nortel solution the best.

Off to the BBQ, the sun is out and it's a beautiful day in NJ! I'll be sure to print this thread for Fletch. I know he reads this forum once in a while, but doesn't post here. Not sure why.

911Guru

http://pbx-e911.com

E911 FAQs are located at:

http://www.tek-tips.com/faq.cfm?pid=798&handle=911guru