We are in the midst of a project moving our VHF fire paging repeater from one tower site which must be demolished to another site across town. We have traditionally controlled our analog equipment over 4-wire DS0 circuits which have proven to be extremely reliable. However, we have run into a snag -- AT&T told us that they are no longer building DS0 circuits and are phasing them out in the near future. We have a local provider which is capable. However, they're cost prohibitive as they don't have equipment in this tower's shelter, etc. So, we're looking at controlling the equipment over IP. AT&T and others are happy to provide a fractional T-1 or other data drop. So, we're wondering what experiences (positive or negative) others may have had with this.
To give you a little more insight, I've setup the proposed architecture as follows: MCC7500 -> CCGW -> 66-block -> Telex IP-233 remote adapter panel -> IP connection -> Telex IP-233 -> Daniels VHF P25 analog repeater.
What do you think? This is our first time using this method. We're trying to do due diligence in every aspect of research since this is the primary means for alerting the fire department (and we absolutely want this to work!). I've obtained the technical manual for the Telex box and read through it and called both Telex & Daniels. But we all know from experience that sometimes things just don't work the way the manual says it should!
Thanks in advance for any thoughts or information you have on this.
Ryan Lee
KJ4WJI
IP repeater control
Moderator: Queue Moderator
Re: IP repeater control
We used the Ratheon NXU-2A units before for the same application and they were reliable.
The weak part is the transport. We ended up going back to fixed RF link/lease line due to unreliable IP network.
Maybe look at a redundant nework of some type or another method of backup for when the IP network goes down.
The weak part is the transport. We ended up going back to fixed RF link/lease line due to unreliable IP network.
Maybe look at a redundant nework of some type or another method of backup for when the IP network goes down.
Re: IP repeater control
Welcome to the 21st century. Yep. Unfortunately, the telcos are getting out of the telco business. They want to sell you access to the cloud, and then you have to figure out how to manage it. DSL service is reasonably reliable, but I don't think you can get them to agree to a five nine rel service contract like you could the leased lines. But, until something better comes along, it may be all you can do.
So, the reason you chose the IP223/IP224 is because you want to maintain tone control of your repeater - correct? Why? If it's just a plain vanilla repeater, then put a control station at dispatch. Or did you mean base station when you wrote repeater?
You basic plan is okay. You need to expand that ip connectivity portion a bit to include a firewall at both ends with a vpn tunnel between them. If your city has an IT dept, have them help you configure and build that out, or sub it, but have the service originate at dispatch. Don't comingle your radio traffic with city network business. If you do, you'll get to learn about network latency and dropped packets first hand. Get your own dsl service that stays dedicated to just radio traffic.
So, the reason you chose the IP223/IP224 is because you want to maintain tone control of your repeater - correct? Why? If it's just a plain vanilla repeater, then put a control station at dispatch. Or did you mean base station when you wrote repeater?
You basic plan is okay. You need to expand that ip connectivity portion a bit to include a firewall at both ends with a vpn tunnel between them. If your city has an IT dept, have them help you configure and build that out, or sub it, but have the service originate at dispatch. Don't comingle your radio traffic with city network business. If you do, you'll get to learn about network latency and dropped packets first hand. Get your own dsl service that stays dedicated to just radio traffic.
Re: IP repeater control
Thank you both for your replies! To Bill, yes base station would be more correct. The machine is capable of being a repeater. However, this is transmit only for VHF fire paging. Good points about firewalls & VPNs. There's definitely an apprehension level since this is new for us so your feedback is definitely appreciated!