GATRRS INTEROP

KTR722

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Am posting this out here because I got asked from a few of you about it from another post where I was referring to some issues with the current RR database regarding the GATRRS Interop channels.

I haven't submitted the changes yet because I am still working on getting all of it actually assembled and verified before I do it. I probably have 97% of it and if anyone here is able and willing to review it, that would be greatly appreciated.

Just for some background, I am a retired chief fire officer that worked fairly extensively with both Travis and Williamson Counties and was responsible for my department's radio system for several years so I had some insider knowledge on how this system was originally designed. The key issue is that I have been out of it for well over a decade and nothing on these systems ever remains static.

The key to understanding GATRRS and its Interop levels is that the original design has 6 layers:

1. Internal Agency TGIDs: this is the lowest level, "owned" by each agency, used for normal day-to-day operations. Examples are: AT PD ADM-IDA sectors for APD, AT FCOM N/S for AFD, and AT EMS CTL/AT MCOM N/S/C/W for ATCEMS.

2. County Service-wide TGIDs: This is the first "INTEROP" Level--per the original architecture. For Travis County, these are the MEDCOM 1-15 channels and FTAC 201-415; Williamson County now uses Fire/Scene channel groups (a change from their original design) and "WC FIRE 01-15" (the original design, these are almost never used, but are still in the radios) for FDs, EMS used to use MedOps 01-15 but are mostly on the same Fire/Scene channel as FD now. Austin PD/TCSO and the local PDs used to have channels called B1 AT LE 01 - B1 AT LE 15 but those are apparently no longer used. I do not know if they still exist in their radios. Austin FD actually used to use FCOM B01-15, ARFF1-3, and FCOM C04-15 for fire ground channels...but that was ditched in favor of the current 3 channel group FCOM 201/204/207....format used now. For all intents and purposes, at least with the ATX/Wilco area, this layer has been completely changed from the original architecture due to operational requirements.

3. County Operations TGID: These channels are required to be in every radio for a specific county. Austin actually has 2 full banks of them, they are D1 AT OP 01 - D1 AT OP 15 for Bank 1 and Bank 2 is D2 AT OP 16 - D2 AT OP 30 ("D1" and "D2" refer to the bank in the radio). Williamson County uses D3 WC OP 01 - D3 WC OP 15. Other counties would be assigned another "D#" number. These channels for Austin are all currently mis-labeled in RR as "AusK R OP01-31" "Regional Interop" channels. To my knowledge, there is no "AusK R OP31" ...because there is no channel "31", at least by the original design. Channel 16 on the selector knob is always 8TAC95 simplex, usually called "DIRECT 16", with the idea being that if you could not see your radio and could only operate it by touch, you could spin the knob all the way to the right and always be on the same simplex channel that bypasses the system, no matter what bank you were on.

4. GATRRS (System-wide) / Regional Service-wide TGIDs: These Interop TGIDs provide common communications among all agencies in GATRRS and with other regional radio systems. All agencies in GATRRS are required to have these TGIDs in each radio. The three services are Public Safety (E1 R PS 01-15); Law Enforcement (A1 R LE 01-14 + a channel called "A1 R LE ALERT") and Public Works (F1 R PW 01-08). These TGIDs are pretty hit and miss right now in RR; they are scattered in several different places and most of them are mis-labeled as belonging to "Aus".

5. GATRRS (System-wide) / Regional Operations TGIDs: These TGIDs provide common communications among all agencies in GATRRS and with selected other radio systems. All agencies/radios in GATRRS are required to have these TGIDs in every radio. These channels are G1 R OP 01 - G1 R OP 15; they are mostly correct in RR other than they are labeled as associated with "Aus" and one channel is listed as being assigned to the State EOC (which it is not, but they probably used it at least once in the past)

6. This is the National "NPSPAC" Mutual Aid level, is the highest level, and technically is outside the scope of GATRRS as they are not system trunked channels; The only key point is that GATRRS radio Zones H, J and K ("I" is not used) are assigned to freqs at this level. There are "K" zone TGIDs in the database that do not belong there because those are (or were) mapped to national mutual aid 8CALL and 8TAC freqs in GATRRS radios.

I will get some more posts out there in the next few days with some more details and some specific TGIDs mapped against it. I think the key is find someone that has current knowledge of the system architecture that can validate any of this, particularly any major changes made over the past decade since i was last involved in any of this.
 

KTR722

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This is old (2008 i think) but it illustrates what I described above fairly well. Just be aware that several of the County Service Talkgroups no longer exist or have been changed, and that this was written when the National mutual aid frequency plans were still in flex. Screen Shot 2020-09-20 at 8.37.22 PM.png
 

KTR722

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[G1] GATRRS (System-wide) / Regional Operations TGIDs
According to the original plan, there are 15 talkgroups named: G1 R OP 01 - G1 R OP 15
These are in the RR DB and other than them being mis-labeled as "Aus"; they look correct.
G1.pngG1RR.png
 

KTR722

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[E1] GATRRS (System-wide) / Regional Public Safety TGIDs
According to the original plan, there are 15 talkgroups named: E1 R PS 01 - E1 R PS 15
These are in the RR DB and other than them being mis-labeled as "Aus"; they look correct. E1 R PS 15 is missing in RR
E1.pngScreen Shot 2020-09-21 at 5.49.39 AM.png
 

KTR722

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[A1] GATRRS (System-wide) / Regional Law TGIDs
According to the original plan, there are 14 talkgroups named: A1 R LE 01 - A1 R LE 14 plus a 15th talk group called "E1 R LE ALERT"

Here is where I need some help.

These are currently in several locations in the RR DB, the first 8 are mis-categorized as being Austin PD Law channels. Also TGID 3421 (RR lists this as "Austin PD Law 6") is apparently now called "channel 15" - not sure if this is the previously-referred to "E1 R LE ALERT" talk group and it has been re-purposed, or if it was mistakenly referred to as LE 15. I have only heard it used once in the past 4 years by an EOC (non-LE) conducting an exercise. The TGIDs apparently do jump from 3420 to 3422 between A1 R LE 05 and A1 R LE 06 (I have confirmed LE 05-LE 09 and LE 11 as being referred to by those numbers), skipping 3421.

The first image is what I have for all the Regional Law talk groups. I have confirmed every talk group has been used in an R LE capacity. The TGIDs with "?" after them, I have not confirmed if that is the correct numerical designator:

A1.pngATRR09.pngA1RR01.png
 
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Thanks for the updates on Interop talkgroups. I have heard the Law talkgroups be called Reg Law 1 03416 on Williamson Simulcast and Honeycomb IR. Located in Leander.
 

Russell

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This is excellent info. The DB has been updated accordingly with some of the info. I've been monitoring this system since APD left UHF. Unfortunately, with Wuhan Flu, I haven't been to Austin this year.

The AusK TGs were submitted about the time the eastern counties (Caldwell, Bastrop, Lee) began to be integrated. Could these be the Regional PW Interop TGs?
 
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KTR722

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This is excellent info. The DB has been updated accordingly with some of the info. I've been monitoring this system since APD left UHF. Unfortunately, with Wuhan Flu, I haven't been to Austin this year.

The AusK TGs were submitted about the time the eastern counties (Caldwell, Bastrop, Lee) began to be integrated. Could these be the Regional PW Interop TGs?
Hi Russell, glad you are seeing all of this. I did not want to submit all of this without some context and some group validation.

Regarding the Regional PW Interops...since i was in public safety, I never really messed with the public works side and the city I worked at did not pay to join GATRRS for public works...

With that said, someone submitted TGID 5323 as "AT PW 01", which could be either the county level interop C1 AT PW 01 or possibly the regional F1 R PW 01 talk group. I have been listening to TGID 5323-5330 to see if I hear anything to validate it as either and I do get the occasional Austin solid waste services or parks unit chatting but usually I just hear dead key-ups from AT PW UIDs so I do not have anything yet to confirm for you.

I was going to wait before I submitted the AusK TG changes (lets figure out the Regional level first, then focus on the county level was my line of reasoning) but if you change "AusK R OP01" to "D1 AT OP 01" and the description from "Regional Interop K1" to "Travis County Interop-Op 01" and use that as the template, you should be good other than changing to "D2" starting with OP 16 (different zone in radio) and, to my knowledge, there is no OP31.
 

KTR722

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[D1-D2] County INTEROP (Travis County) Operations TGIDs
Austin/Travis County has/had 30 OP talk groups, programmed into 2 zones (D1 and D2), 1st 15 were in D1, 16-30 are in Zone D2. "AT" is the programming designator used in the radios for Austin/Travis county.

Screen Shot 2020-09-21 at 11.27.52 AM.pngScreen Shot 2020-09-21 at 11.35.18 AM.pngScreen Shot 2020-09-21 at 11.38.10 AM.png
 

KTR722

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...to my knowledge, there is no OP31.
The TGID listed as OP 31 (TGID 5321) apparently does get used some. From what i have captured, it looks like AT PD GEO was patched into it for a while and a CAD upgrade was done with TCSO, ATCEMS, AFD and APD all coordinating the upgrade on this.

From a purely lazy standpoint, if you assume TGID 5320 is the last OP 30 talk group, it would make sense to start the PW talkgroups on 5321-5328 if you are just going down the spreadsheet assigning them when you initially setup the groups...

I have never heard anything on 5321 but have heard/recorded traffic on 5320 and 5322-5328. I have never heard or recorded anything on 5329 or 5330.

A CAD upgrade makes sense for C1 AT PW 01...patching AT PD GEO sector radio into it does not...unless they needed assistance from public works (road closures perhaps?) for any of the myriad crazy events we have had downtown this year...
 

Russell

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The TGID listed as OP 31 (TGID 5321) apparently does get used some. From what i have captured, it looks like AT PD GEO was patched into it for a while and a CAD upgrade was done with TCSO, ATCEMS, AFD and APD all coordinating the upgrade on this.

<- SNIP ->
APD George Regrouped

During a previous occasion of riots in downtown Austin PD George was dynamically regrouped to another TG. I suspect this occurs when APD needs larger scale backup or they suspect regular channels are clearly being monitored by organized rioters.

IIRC 3421 was similarly used during a shooting at UT Campus a few years ago where multiple agencies swarmed the campus. During that event all non-PD traffic was administratively pushed to the other Layer and lower priority users were getting widely bonked.
 
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