Here's an informational presentation I found on the Northern California APCO (NAPCO) website that shows the timeline of this statewide system, and all the expect site locations throughout California. It also goes a bit into the naming structure of some of the talk groups, and how they would like the system to hand-off to other regional systems, if they cooperate.
NOTE: I've submitted via an archive.org link instead of directly via the NAPCO website so it doesn't disappear on us:
Keynote: Eric Dye, California OES, Statewide California Radio Interoperability System (CRIS)
This is a great find! Thank you.
As someone who currently lives in an area that borders three states, two who already have statewide P25 trunking systems in use (Ohio and Indiana) and another that is looking to build one (Kentucky) I like what they are doing here in California.
I would highly encourage them to pursue the "system of systems" approach as much as possible. If you think about it, a lot of the area they want to cover in the first few years is already covered by P25 trunking systems so if they spent a majority of that time/money working to link those systems into one large system (as Ohio did) they wouldn't need to build sites from scratch. They could then use the savings from that approach to build new (state owned) sites in the more rural areas and they would probably be able to get the entire system on line sooner.
In Ohio they have several tiers for the "system of systems"
Some agencies own and operate their own sites and link them to the state core. Those agencies don't pay subscriber fees because they are paying to maintain the sites.
Some agencies build the sites and then hand them over to the state for a credit (sometimes lasting several years) on subscriber fees.
Some agencies turn over their spectrum to the state for a credit on subscriber fees and allow the state to build the sites.
Some agencies are just subscribers and pay the standard fees and the state builds sites to cover those areas.
This seems to work very well and just about everyone is now on the statewide system.
As for talkgroup naming and partitioning, this is very important and California seems to be deviating from what is done elsewhere. Most talkgroups on statewide systems start with a two or three digit county number that is derived from an alphabetical listing of the counties. They then allow each agency to select the remaining part of the talkgroup name as long as it's easy to identify the use(r) from the name. In Kentucky they are already starting to do this on new P25 systems even though they are not linked statewide.
Each county/large city/large agency is given a block of 500 talkgroups to use as they see fit. If the county/city/agency needs more than 500 talkgroups (this is rare) they can apply for more and if the application is approved they are normally assigned additional talkgroups from an overflow block.
The talkgroups are partitioned so as the majority of the primary talkgroups are locked to the home site with tactical or multi agency talkgroups allowed to roam to sites that are one ring around the home site. Each agency is also allowed a few talkgroups that will roam statewide.
Most state agency talkgroups are allowed to roam statewide.
The systems also have statewide, regional and local "mutual aid" talkgroups that are setup by the state that are also allowed to roam statewide.
