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Your PBX has been hacked

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Re: Your PBX has been hacked

#41

Post by drzaiusapelord »

MichaelGG wrote: post #33
evunveot wrote: post #25

It would be great if there were a * 69 type system that all the carriers supported (i.e. was imposed by the FCC) where dialing * 7786 (* SPAM) or something would flag the previous incoming call as unsolicited spam/scam and allow you to leave a voicemail with the FCC describing what happened. Hopefully the metadata would be fresh enough in the moment that they could meaningfully record the actual route of the call as…

CDRs are kept for quite a while, so it's possible/easy to track these calls down. There are a bunch of intermediaries (I ran one), and each time you need to get them to release customer information. The FCC doesn't care enough; no one investigates.

Okay we do the legwork and track him down. He's an Indian national using a stolen or prepaid credit card in Mumbai and using voip.ms or flowroute or whoever just needs a CC to get started. He has long left this service and gone to another by the time you "catch" him. He's made millions of calls since.

Re: Your PBX has been hacked

#42

Post by pastycrinkles »

caruizdiaz wrote: post #36
pastycrinkles wrote: post #20

Earlier quoted context omitted.

Right, because voip has a reputation for sounding great and being reliable. (/s)

If you do Skype or WhatsApp you can prove yourself wrong. No one is saying VoIP is as reliable as PSTN. Not even mobile (GSM, CDMA, etc.) is.

You clearly haven't made any PSTN calls on Skype. If you're looking for higher sample rates, it's relatively easy to use a B channel to transport g.722, or even bond a couple together for 128k AAC/MP3/any other codec you'd like.

Not only do you not have to deal with the problems of internet routing, you aren't stuck with underwater sounding CELP codecs.

Anyway, if you're arguing voip should replace the PSTN, I'd hope you'd at least have something hinting it could be as reliable.

Re: Your PBX has been hacked

#43

Post by jallmann »

pastycrinkles wrote: post #35
jon-wood wrote: post #30

Earlier quoted context omitted.

Done well, yes, it does. Just about any corporate call these days is going to be going over VoIP because it provides so much more flexibility. Just because a cheap ISP provides crappy VoIP doesn't mean the system is fundamentally flawed.

Maybe with dedicated fiber links that carry no other traffic, sure. But the vast, vast majority of voip routes tend not to measure up to their circuit switched counterparts. Why do you think things like T.38 and RFC-2833 exist?

> vast majority of voip routes tend not to measure up to their circuit switched counterparts

Most VoIP calls are also carried as plain data traffic. Digital voice services, which are basically VoIP (VoLTE, AT&T U-verse, etc), properly differentiate between calls and data, so calls on these networks are going to be much more reliable than simply leasing a SIP trunk. Once reliability is in place, audio quality is certainly going to be better between compatible endpoints.

Re: Your PBX has been hacked

#44

Post by caruizdiaz »

pastycrinkles wrote: post #42
caruizdiaz wrote: post #36

Earlier quoted context omitted.

If you do Skype or WhatsApp you can prove yourself wrong. No one is saying VoIP is as reliable as PSTN. Not even mobile (GSM, CDMA, etc.) is.

You clearly haven't made any PSTN calls on Skype. If you're looking for higher sample rates, it's relatively easy to use a B channel to transport g.722, or even bond a couple together for 128k AAC/MP3/any other codec you'd like. Not only do you not have to deal with the problems of internet routing, you aren't stuck with underwater sounding CELP codecs. Anyway, if you're arguing voip should replace the PSTN, I'd hope…

> You clearly haven't made any PSTN calls on Skype.

I did, and the reason some calls sound horrible, is because Skype is trying to save up some money hiring shitty carriers/providers.

> it's relatively easy to use a B channel to transport g.722

Why would you use an HD codec to transcode to G711? Call on any direction can sound only as good as G711.

> Anyway, if you're arguing voip should replace the PSTN, I'd hope you'd at least have something hinting it could be as reliable.

I agree with most of your arguments. VoIP isn't ready now, but it will be soon. Just remember how the Internet was 10 years ago, and how it is today.

Re: Your PBX has been hacked

#45

Post by pastycrinkles »

caruizdiaz wrote: post #40
pastycrinkles wrote: post #35

Earlier quoted context omitted.

Maybe with dedicated fiber links that carry no other traffic, sure. But the vast, vast majority of voip routes tend not to measure up to their circuit switched counterparts. Why do you think things like T.38 and RFC-2833 exist?

> vast majority of voip routes tend not to measure up to their circuit switched counterparts That's because circuit switching is literally setting up a wired connection between two points. Good luck trying to be that reliable with a population the size of the Internet, and if you can, good luck being able to pay and maintain an infrastructure of that size. > T.38 and RFC-2833 exist Really? The last time I sent a fax…

> Really? The last time I sent a fax was 2006.

You're clearly missing the point here. T.38 and RFC-2833 largely exist because there's many, many voip routes that can't transport low latency audio reliably. There's a lot of other things you can transport in a phone call that don't have out of band standards.

If you require out of band standards to reliably transmit a fax or even something as basic as DTMF, you're clearly stifling what can be done within a perfectly valid form of transport.

> Good luck trying to be that reliable with a population the size of the Internet, and if you can, good luck being able to pay and maintain an infrastructure of that size.

Several companies have, and continue to do just that not just around the country, but around the world; end offices that serve customer lines are connected together by trunks to tandem switches. You clearly have no idea how the phone network works.

> That's because circuit switching is literally setting up a wired connection between two points.

It's not just one channel, though; techniques such as time or frequency division multiplexing allow you to stick thousands of calls over a cable or RF link.

Re: Your PBX has been hacked

#46

Post by pastycrinkles »

jallmann wrote: post #43
pastycrinkles wrote: post #35

Earlier quoted context omitted.

Maybe with dedicated fiber links that carry no other traffic, sure. But the vast, vast majority of voip routes tend not to measure up to their circuit switched counterparts. Why do you think things like T.38 and RFC-2833 exist?

> vast majority of voip routes tend not to measure up to their circuit switched counterparts Most VoIP calls are also carried as plain data traffic. Digital voice services, which are basically VoIP (VoLTE, AT&T U-verse, etc), properly differentiate between calls and data, so calls on these networks are going to be much more reliable than simply leasing a SIP trunk. Once reliability is in place, audio quality is certa…

> Digital voice services, which are basically VoIP

You say that as if things like GR-303 and ISDN BRIs/PRIs don't exist. The only thing that isn't digital about modern, non-IP phone networks is the last mile when you order an analog loop.

> properly differentiate between calls and data, so calls on these networks are going to be much more reliable than simply leasing a SIP trunk.

In theory, sure. As I said though, in my experience the vast majority of these routes tend to fall behind their circuit switched counterparts in performance even on carrier grade routes.

Re: Your PBX has been hacked

#47

Post by agwa »

wtallis wrote: post #38
agwa wrote: post #14

Earlier quoted context omitted.

There are significant downsides to technically prohibiting caller ID spoofing. First, you would no longer be able to preserve caller ID when forwarding calls. Consider how much less useful Google Voice would have been if you couldn't see the caller ID of calls forwarded to you. Second, in VoIP, outgoing calls (termination) and incoming calls (origination) are completely decoupled services. This is really nice because…

As a Google Voice user, the downside would be sad but totally worth it if it meant I could have GV accurately screen my calls. I could still get full caller ID information for GV calls received through VoIP, and when receiving calls through POTS I could at least know that the call is from somebody I'm willing to take calls from. The other use case applies pretty much only to people I don't want to hear from in the fi…

It sounds like the list of people you're willing to receive calls from is pretty small. Have you ever actually received a phone call which spoofed the caller ID of someone you know? I haven't - all the spoofed calls I receive are from numbers I usually wouldn't answer anyways since I don't recognize them.

Also, note that Google Voice no doubt uses many termination providers (considering they're giving the service away for free, they'll need some pretty sophisticated routing to take advantage of cheap rates), so the second use case applies to any Google Voice user.

Re: Your PBX has been hacked

#48

Post by pastycrinkles »

caruizdiaz wrote: post #44
pastycrinkles wrote: post #42

Earlier quoted context omitted.

You clearly haven't made any PSTN calls on Skype. If you're looking for higher sample rates, it's relatively easy to use a B channel to transport g.722, or even bond a couple together for 128k AAC/MP3/any other codec you'd like. Not only do you not have to deal with the problems of internet routing, you aren't stuck with underwater sounding CELP codecs. Anyway, if you're arguing voip should replace the PSTN, I'd hope…

> You clearly haven't made any PSTN calls on Skype. I did, and the reason some calls sound horrible, is because Skype is trying to save up some money hiring shitty carriers/providers. > it's relatively easy to use a B channel to transport g.722 Why would you use an HD codec to transcode to G711? Call on any direction can sound only as good as G711. > Anyway, if you're arguing voip should replace the PSTN, I'd hope yo…

> Why would you use an HD codec to transcode to G711? Call on any direction can sound only as good as G711.

The idea is to use the timeslot g.711 normally would sit in to transport your own codec. Studios use this technique pretty frequently when they hire voiceover talent or do remotes.

Re: Your PBX has been hacked

#49

Post by wtallis »

ryanlol wrote: post #11
wtallis wrote: post #9

Earlier quoted context omitted.

That's only because we let that system be gamed. It doesn't have to be that way . Telcos always know who they're billing for a call; they have the capability to make caller ID reliable.

I don't think you've seen the systems they use in developing countries. Phone networks are almost a century behind the internet. It's not something that's easy to fix, nor are there too many situations where you would need to rely on the CID to identify the caller.

You're still using the circular logic of insisting that caller ID can't be trusted because it shouldn't be trusted because it can't be trusted. I and most people who want to not get robocalls want a caller ID system that is trustworthy, and the first-world telcos we're doing business with are totally capable of providing a service that is at least partly trustworthy. I'm not interested in receiving calls from third-world countries and would be perfectly happy only getting calls from those using providers that provide for trustworthy caller ID, but nobody's even offering to sell me such a service.

Re: Your PBX has been hacked

#50

Post by jallmann »

pastycrinkles wrote: post #46
jallmann wrote: post #43

Earlier quoted context omitted.

> vast majority of voip routes tend not to measure up to their circuit switched counterparts Most VoIP calls are also carried as plain data traffic. Digital voice services, which are basically VoIP (VoLTE, AT&T U-verse, etc), properly differentiate between calls and data, so calls on these networks are going to be much more reliable than simply leasing a SIP trunk. Once reliability is in place, audio quality is certa…

> Digital voice services, which are basically VoIP You say that as if things like GR-303 and ISDN BRIs/PRIs don't exist. The only thing that isn't digital about modern, non-IP phone networks is the last mile when you order an analog loop. > properly differentiate between calls and data, so calls on these networks are going to be much more reliable than simply leasing a SIP trunk. In theory, sure. As I said though, in…

> You say that as if things like GR-303 and ISDN BRIs/PRIs don't exist.

Granted, "digital voice" was imprecise terminology, but you get the gist... modern consumer phone services are VoIP.

> fall behind their circuit switched counterparts in performance even on carrier grade routes.

Most carrier backbones have been all-IP for years. Pretty sure end-to-end circuit switched calls are atypical nowadays, although I'm happy to be proven wrong.

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