| Telecoms guy here. Firstly CLI blocking is easy to get around. Faking CLI is very easy. There is a field within SIP that is refereed to as P-assert. The idea is that this field always contains the billable number. However I know of at least 3 sip carriers you could sign up today with, have numbers within 10 minutes and they allow you to put ANY CLI and P-assert. Then you can bridge in to the TDM and almost untraceable. CLI faking is very common. There is a requirement in the UK that no calls gets in to the network without a p-assert but the network is to complex these days, there is always a way to get a call in with what ever information you want We have been working on a blacklisting service as well. we have 2 types, the personalized white and black list (so a parent can have a white list for their kids phone): i think i agree with the FCC that global block lists are a bad idea (too easy to get someones number blocked for lulz). The second looks up the CLI and checks a number of those "who is calling me sites" if the number is know for spam it does not get to the phone and starts reading the comments back to them about their number (cli will get round this). Both ways have issues. The reason I bring this up is because we become an MVNO and in turn run our own sim cards. This meant that we could have had the blacklist/whitelist without messing with the call flow to much. This also allowed you to dial 9 to block the last number that called you was sexy but meh too much work to run an MVNO and just no money in it. We will see. Lots of changes will be happening in telecoms in the next 5-10 years. webRTC could flip the existing telecoms models on their heads, if only someone could get some traction. Ramble Ramble, i rare have anything to say :/ |