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Part 97 Interpretation- IP Phone Deployment over mesh

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K7BUM's picture
Part 97 Interpretation- IP Phone Deployment over mesh

*Admin- Please move to appropriate forum if this one is not*

I’m reaching out to you to get your interpretation of Part 97, third-party traffic and how it relates to Mesh Networking. I do apologize ahead of time for the long-winded post.

My assertion is that the use case illustrated below is not a violation of Part 97 and how it relates to 3rd party traffic.

The following are my assumptions/definitions:

  • A mesh node is considered to be an automatic data relay device that operates its radios on Amateur (Part 97) frequencies;
  • The mesh nodes are password protected to disallow reconfiguration.
  • The SSID of the node contains the amateur callsign of the control operator (e.g., K7BUM-NODE1, AK7AR-BASE);
  • “IP Telephones” are telephonic devices that convert voice audio into a digital data stream
  • A Private Branch Exchange (PBX) is a device that routes these telephonic data streams to the intended IP telephone devices.


Figure 1 is a block diagram illustrating the typical use case where 3rd party traffic can come into play:



Public Service Event,  Event Director (NON-Amateur) at Site “A”, Mobile Communications Unit (Amateur Operators)at Site “B” and Aid Station (Mix of amateurs/non amateurs) at Site “C”.

1.)Aid Station Worker (non-amateur) at “C” picks up the IP Phone and dials the race director (non-amateur) at site “A”. They have a phone conversation. This constitutes 3rd party traffic on the mesh network.

Does this constitute a violation of part 97?

Here is Part 97.115 (part that covers third party) downloaded from ARRL website- I’ve highlighted  the part I believe that makes the scenario above legal Part 97.115 (c):

“§97.115   Third party communications.

(a) An amateur station may transmit messages for a third party to:

(1) Any station within the jurisdiction of the United States.

(2) Any station within the jurisdiction of any foreign government when transmitting emergency or disaster relief communications and any station within the jurisdiction of any foreign government whose administration has made arrangements with the United States to allow amateur stations to be used for transmitting international communications on behalf of third parties. No station shall transmit messages for a third party to any station within the jurisdiction of any foreign government whose administration has not made such an arrangement. This prohibition does not apply to a message for any third party who is eligible to be a control operator of the station.

(b) The third party may participate in stating the message where:

(1) The control operator is present at the control point and is continuously monitoring and supervising the third party's participation; and

(2) The third party is not a prior amateur service licensee whose license was revoked or not renewed after hearing and re-licensing has not taken place; suspended for less than the balance of the license term and the suspension is still in effect; suspended for the balance of the license term and re-licensing has not taken place; or surrendered for cancellation following notice of revocation, suspension or monetary forfeiture proceedings. The third party may not be the subject of a cease and desist order which relates to amateur service operation and which is still in effect.

(c) No station may transmit third party communications while being automatically controlled except a station transmitting a RTTY or data emission.

(d) At the end of an exchange of international third party communications, the station must also transmit in the station identification procedure the call sign of the station with which a third party message was exchanged.”

 I appreciate your time and attention in this matter- If there are any questions, please respond...

Seems you have answered your

Seems you have answered your own question.  So I am not really sure what the point of it was.  In terms of 3rd party regulations its no different than the packet radio internet gateways of 20+ years prior.  (and more recently winlink)  Communications originating from non amateurs, but being passed automatically by amateur stations is nothing new.  Now on to more productive things...

K7BUM's picture


I did use the Winlink example, didn't even think about packet... Thanks. Wasn't as "un-productive" as you thought. Certainly isn't my intent to waste anyone's time- I thought: "If anyone has been through this discussion, it will be the AREDN group." Frankly, I'm a fairly well educated guy and can read the FCC regs. This one is is pretty cut and dried to me. 

It was more of a validation more than anything from additional EMCOMM groups.

I'm a relatively new amateur (< 3 years) and there are a few "Old timers" that are causing fear, uncertainty and doubt (FUD)... "You guys are going to violate FCC regs and are  going to get the entire county group in trouble"... All it takes is a couple of individuals to upset the apple cart. Honestly, I can probably produce every regulation on the planet and a assurance from the FCC chief, and it still won't be good enough. The FUD is holding up both the tactical and base deployment of our PBX systems, however...

Thanks for the response, it was more helpful than you think.



K6AH's picture
Not all Ham Radios have Microphones

Hi Mike,

Hams are used to their radios having microphones... and when these devices don't your ham buddies have found what they think is a surrogate.  However, the VoIP phone is not the equivalent of the elusive microphone.  As you know, it is simply another IP-device that resides on the Ethernet network.  Under section 97.115(c), as you've pointed out, these stations "...may transmit third party communications while being automatically controlled" because their transmissions are data emissions.

This means the control operator, so long as he/she is able to shut the station down should it begin to operate improperly, does not need to be present.  Think of the automatically controlled station as a repeater or digipeater and the ham owner/operator is the station’s trustee.

And this is the last I’ll say on the subject.  I’ve been involved in too many debates over questions like this over the years.  The bottom line is, I’m not a legal expert on the subject… none of us are.  So best to leave these arguments to those who are.  I will say, if these practices were illegal, I doubt the ARRL would have awarded us their 2014 Microwave Development Award... endorsing a technology that puts all of our FCC licenses at risk ;-)

Andre, K6AH

K7BUM's picture
Physical Security


Thank you- I agree 100% with that last statement... I also think where most folks are getting hung up is that these phones/devices are going to be distributed willy-nilly- My major concern isn't someone picking up an IP phone and making a crank call to the EOC, but actually one of physical security- Using my initial example, if I have a remote unattended node at the Race director's office, someone could run off with a $110-120 Ubiquiti Bullet or Nano, reflash it back to AirOS and have a nice access point for their dorm room...

I'm an IT guy by trade for a large semiconductor manufacturer- I've seen some decisions made by the network security guys that are laughable... I really like the discussion regarding firewall rules and monitoring but forget the USB port on the front of the server....

Best regards-




K5DLQ's picture
Just put a sticker on the

Just put a sticker on the node:

Property of <your county> Sheriff's Office.  This device is GPS trackable.



K5DLQ's picture
The way I see it, is that the

BTW, I do see this discuss as valid and relevant.

The way I see it, is that the control operator must still be present and be monitoring when the VOIP calls are made. The expectation should be set that even though it's a VOIP phone, you still need a licensed operator present.


ke6bxt's picture
Yes I agree!  See my

Yes I agree!  See my explanation below.

My apologies to the original

My apologies to the original poster.  I just get a bit annoyed by all the armchair lawyers in the hobby.  I believe the time is better spent carrying on experimenting quietly and ignoring them.  I have said it many times, the rules change as we do.  But now that I know its a group concern that is kind of a hold up, it makes sense.

You are correct this is a bit different.  Traditional 3rd party is where just one party is the non-amateur.  Think autopatch. But 3rd party to 3rd party, while less common is permitted.  (At the boy scouts jamboree on the air, we do this)  It's just a matter of supervision from a licensed person.  I don't think they need to be present where the two 3rd party people are having the conversation, just monitoring and able (a control point) to end the communications if something improper arises.

Asterisk's chanspy and a ssh connection might be all you need to do this from a far.

ke6bxt's picture
Third Party traffic on an AREDN network
§97.3(a)(47) Defines Third party communications as: A message from the control operator (first party) of an amateur station to another amateur station control operator (second party) on behalf of another person (third party). 

§97.115(c) does not apply to third party traffic on an AREDN network because we are specifically exempted because our RF emanations on Amateur Radio frequencies are "data emissions".

§97.115(b)(1) and ​§97.115(b)(2) does apply, however.

§97.115(b)(1) requires that the control operator be present.
"The control operator is present at the control point and is continuously monitoring and supervising the third party's participation".
This is not telling a non-ham, "There's the phone, and those are the phone numbers/ip addresses. See you latter"

§97.115(b)(1) and ​§97.115(b)(2) further restricts who can not be a third party. In your example above, if the Aid Station Worker or the race director used to hold an Amateur Radio license but had it revoked, then they could not be a third party.  If they never had an Amateur Radio license, they can operate as a third party as long as they are continuously monitored and supervised by a licensed Amateur Radio operator.


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