I've developed a fix that matches the IP address of the sender of the OPTIONS (Asterisk in this case) against the IP address of registered/authenticated users. Upon a good match, the OPTIONS is replied to. If there is no match, the OPTIONS will not be answered.
There are some cases where Asterisk is sending us OPTIONS without first having a valid registration. In the future, these requests will not be answered. I'm going to look into what is causing this particular condition. These are a minority of the total number of OPTIONS requests.
Regards,
Norm
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