Because of the weak response to my previous posting (2 Feb.2014), I'm once again asking the newsgroup readership to help form a grassroots alliance to get illegal robocalling stopped. The method is detailed in my entry to the 2012-2013 FTC Robocalling contest. See
In my opinion it will be fruitless to try to stop these calls by threats, making them illegal, etc. This will work only if the callers can be identified and prosecuted easily. Therefore, my proposal relies on technical means to actually stop most calls from completing. The method is based on caller ID (CID) information delivered with the calls. It requires development of new features to be deployed in the phone network.
My proposal works by dividing robocalls into two categories. Category 1 calls are delivered with a valid CID. Here, "valid" means a) the recipient of the call can dial the CID and the call will go to the entity (PBX, etc.) that placed the robocall, and b) the calling entity will have a billing address at which enforcement authorities can find the robocallers if they are pursued because the calls are illegal. Category 2 calls are delivered with a blank or fake (spoofed) CID. It is presumably difficult to get a billing address for such calls. My hypothesis is that most illegal robocalls are in this category.
Category 1 calls cannot, in my opinion, be identified as illegal via technical means (remember that some such calls are not illegal). Therefore I favor a method for recipients of calls to report them (via dialing a new "vertical service code" such as *99) into a new database. Searches of the database on various criteria by enforcement authorities should identify the largest-scale culprits fairly easily.
Category 2 calls must have their CIDs flagged as improper. This must be done by the first switching entity that qualifies as part of the public switched telephone network (PSTN) that a call origination reaches. This switching entity must be configured with a new feature that identifies any customer-provided CID as valid or spoofed. It must be able to do this because it is the same entity that routes calls TO the customer when that same CID is dialed elsewhere on the PSTN. This switching entity must send the valid/spoofed information in the signaling messaging accompanying every call origination. Signaling standards support support this information in a "screening indicator".
Switches that receive calls to be sent to one of their connected phones must also implement a new feature to check the signaling of incoming calls. If the CID was spoofed, the switch simply blocks the call. I propose additionally that the switch itself "answer" the call in order to create a charging record for the caller.
Finally, we need to be aware that some telephone companies may inadvertently or willfully violate their public trust and incorrectly label spoofed calls as valid. For this purpose we need yet another feature to label every telco as trusted or not. My proposal to do this is another database that can be resident within the signaling system. Any call received by a trusted telco from an untrusted telco would have its CID screening indicator flagged as untrusted. If the indicator is untrusted, the switch for the terminating phone can take a variety of actions, including call blocking.
Many more details are given in the proposal whose link is above. I seek comments on the proposal and on how we can get it to happen. Because the economics do not appear favorable for telcos, at least at first, my thinking is that regulatory action is needed. So far, my contacting the FCC has not been successful. I'm considering contacting my congressman next. Constructive comments on both the technical and "political" aspects of this issue are welcome.
[moderator pro tem's note: I discussed this with the poster. It's an interesting concept, and probably would work technically were it implemented and required. The probem is that it requires changing switch software in existing old DMS and 5E switches, and in the SS7 network. That stuff is old, not well supported, and the telcos are just letting them rot in place. So trying to get them to do anything would be extremely difficult. Comments from the rest of the readership are welcome!]