Unitrunker P25 "Denied" message

There is a new Harris P25 phase 2 system here that is on the air but not in use yet.
A couple times I ran Unitrunker for several hours and the call history logged a "Denied" message when there was no other activity going on. Source and Target were the same radio ID and there was no talkgroup active and no radios logged on or joined.
Other times I saw radios log on, join several talkgroups and log off. It looked like they scrolled through a bunch of channels and turned the radio off or changed systems.

Does "Denied" mean that a radio ID was not allowed on the system? Does it mean different things on P25 than SmartZone?

What message does Unitrunker show on P25 when two radios try to talk on the same talkgroup at the same time?

When you see a denied message it means that there are not enough trunked channels available for the user to use. They get a denied message on their radio as well. They then have to key up a second time to successfully transmit.

It can also mean that the talkgroup the radio was trying to affiliate on that site was not authorized on that site. Hope that makes sense.


Sent from my iPad using Tapatalk

bwca44 said:

When you see a denied message it means that there are not enough trunked channels available for the user to use. They get a denied message on their radio as well. They then have to key up a second time to successfully transmit.

Click to expand...

Cool, thanks for sharing that tidbit.

bwca44 said:

When you see a denied message it means that there are not enough trunked channels available for the user to use.

Click to expand...

That's not what is happening here. I did it when there was no active talkgroups or voice channels.

nd5y said:

That's not what is happening here. I did it when there was no active talkgroups or voice channels.

Click to expand...

See my reply above

I see these messages periodically on Missouri's statewide multi-site system.

There are a few that are puzzling because the talk group has been active on the site in the past, and there are idle voice channels.

I sometimes wonder if the deny message is due to the lack of an idle voice channel on another site that has an affiliated radio in that same talk group ?

talkpair said:

I see these messages periodically on Missouri's statewide multi-site system.

There are a few that are puzzling because the talk group has been active on the site in the past, and there are idle voice channels.

I sometimes wonder if the deny message is due to the lack of an idle voice channel on another site that has an affiliated radio in that same talk group ?

Click to expand...

In the GUI interface, I'm not sure if Unitrunker distinguishes between registration denial vs. affiliation denial vs. system busy message (i.e. at that moment no frequency is available), I can't recall for sure. However, you can see these messages in real-time in the DSD+ terminal log.

With P-25 there are two (2) main types of access-based denials. First, during the registration stage a radio ID can be denied from registering on the system, RFSS (Zone) or individual site. Second when you try to affiliate with a talkgroup on a particular site, the site can deny access to that talkgroup.

As noted above, you can also have a transient "denial" because all frequencies are busy at that moment in time. However, the "busy" period is typically of very short duration. I don't believe Radios typically roam to another site just because of a busy message.

Hi Tom;

P25 messaging includes the Denied Response and the Queued Response. The program generally displays Denied Response messages as "Denied". Queued Response messages generally appear as "Busy". To see a specific denial reason, you'd have to look in the decode log.