Leveraging Cisco IPICS and Cisco ISSI for interoperable communications

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Thunderbolt

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RENO, Nev. -- The combined solution takes radio transmissions — whether they’re digital or analog signals — from the radio tower and feeds those signals into a router that then converts the voice radio traffic into IP

PoliceOne.Com
 

jim202

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Seems Twisted Pair's Wave System does this to.

This is about standard for everyone that has any IP connection at all. Don't know why they are thinking it is any better than the rest of the average units on the market. Tell us something new that no one else has or can do.
 

Thayne

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Most everything we all have works well until it doesn't:p

(Except for blow-up chinese plastic toys--they never work even when the kids first rip the box open)
 

greenthumb

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I wouldn't trust IP for Public Safety comms. In house maybe, but not out in the wild.

Much of the public safety in Colorado does (to the order of nearly 7 million calls per month), much of those same agencies in Michigan do, including Detroit. I could really go on, but if you look through the RR database and see that it's a Project 25 system, chances are very, very high that it uses IP for transport.

The days of doubting IP as a viable transport for public safety communications are long over.

Nevertheless, it should be interesting to see how Cisco markets their ISSI product since most vendors need translation from their proprietary network protocol to the ISSI standard protocol in order to make it work. And at that point, why get Cisco involved since what you've purchased from each 'side' of the link's manufacturer gets you into the ISSI cloud anyway?
 
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jim202

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I wouldn't trust IP for Public Safety comms. In house maybe, but not out in the wild.

I would suggest that you go do some homework on this IP for Public Safety that you don't trust. Many of the installed and well respected communication systems and gateways have been using this format for years.
 

radioman2001

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I didn't say you couldn't, I said I wouldn't unless it's a dedicated circuit. IP is funny, some times the packets don't get there in the same order they left. That's whats great about IP, there is always an alternate route, but with that you can get packets out of order, or not have a high enough priority that they can sometimes get left behind. Your computer doesn't care, it may load different parts of a web page not in the order, but audio has to arrive in the correct order and at the right time. Specific setting in the routers must be used to prevent problems like that.
As far as after the local exchange, it's not IP but probably T-1 or T-3 circuit, a whole different animal. For those agencies using them successfully, that's good, I am just not all that confident with it after problems with some VOIP circuits we have. Maybe the newer stuff address that.
Also it's funny how most everyone in Public Safety now doesn't consider audio delays as a problem, as it was first thought of in the 80's. Some of the early rolling code scramblers had a 1/2 sec delay, which was not considered acceptable at that time. Now a days with all the digital stuff 1 sec is common.
 

greenthumb

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I wouldn't go so far as to say that 1 second delay is common. I would call that more of the extreme, and would indicate some kind of backhaul latency problem to me. My experience has been that about 500 ms is closer to 'common' when using a multi-site system with long links. Most radio systems that are using IP for their backhaul are generally sending their WAN on a DS1 circuit and not Ethernet...and certainly not into BGP-land on the internet (you're asking for mega-delay if you do that!).
 
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