zz0468 wrote:It's not going to change any minds as to whether or not to encrypt.
Definitely agree there. Also, it seems that usually by the time people find out a channel or system will be encrypted, the decision to encrypt was made months or years in the past. We know the decision to encrypt often comes from within the agency, but it would be interesting to know exactly who within the agency is tasked with making the recommendation or decision. How critical is the part the vendor's representative plays in persuading an agency to encrypt? It seems that often times, as in the case of Beaumont PD, the agency will hire a technical consultant to make recommendations about system design prior to vendor selection, and the consultant will almost always recommend full encryption.
N6AJB wrote:The article continues on to argue against encryption from the standpoint of interoperability. This makes no sense to me from an operational standpoint.
I think you make some good points, but I'm going to push back a little on your interoperability statement. These are my personal inexperienced views. If I have misunderstood something, please correct me.
N6AJB wrote:There are dedicated clear channels set aside specifically for interoperability on all the public safety bands and most governing agencies that oversee these channels (Cal-EMA) here in Ca., and Federal agencies have policies in place that ban or discourage encryption on the interoperability channels.
True, and I sincerely wish agencies would use these channels. For the most part, at least in this area, they seem disinclined to do so. The only usage I have ever noted in this area is interagency surveillance operations and supplemental single-agency usage.
N6AJB wrote:Interoperability on PRIMARY channels does not happen on a day to day basis anyway, largely due to the fact that different agencies use different frequency bands, different emission types and in many cases different proprietary systems.
That may be true in Riverside County, but many other areas including San Bernardino County are increasingly moving to shared trunked systems. In these cases, practically the only
technical barrier to talking on another agency's primary channel is having it programmed into your radio with the ability to transmit. I have heard this work fairly well between San Bernardino County Sheriff and Redlands Police, for example. In a recent incident, a sheriff deputy was at the city boundary and noticed a house on fire within the city. He responded to the location, switched over to the city's primary channel, and provided mutual aid as the first emergency personnel on scene.
Now, there are definitely some drawbacks to this type of interoperability, and I don't think it's an appropriate solution for every interoperability need. We can all debate the viability/desirability of it without coming any nearer to agreement, and each agency will make its own decisions about interoperability. But it definitely provides some pretty big benefits to operational efficiency that should not be overlooked. There are many incidents from my monitoring experience where LE agencies had absolutely
horrible interoperability because the messages had to pass through multiple dispatchers.
The very purpose of encryption is to keep everyone out except a specific group of known subscriber units. When an individual agency handles its own encryption, the method that is easier to manage, they rarely consider other agencies, being focused on their own needs/wants. If they do wish to provide access to other agencies, they face the significant complication of having to handle encryption key management for an outside agency's radios. This increases vulnerability of the key because it is given to an agency outside the managing agency's control. And what if the agency inadvertently excludes a particular allied agency from their approved group of subscriber units they would otherwise have wished to include? All of these have the effect of restricting primary channel interoperability. Of course, if an agency doesn't care about having it, all this is moot.
I know law enforcement agencies usually don't care about interoperability nearly as much as fire agencies, but I think all law enforcement agencies should have these three kinds of interoperability solutions: (1) pools of shared channels dedicated exclusively to interoperability, (2) access to allied agency primary dispatch channels, and (3) a shared interoperability channel for emergency broadcasts with subscriber units dedicated to exclusive 24/7 monitoring.