Question About PBX

Hi y’all!

I should start by apologizing. I really am sorry. I know I am a complete noob/idiot. I know I don’t belong on here.

However, I am starting a grassroots organization/project/effort and, due to the terms of the grant (which was based on my vision for the project), we are unable to commit to any reoccurring expenses (VoiP service, for example).

However, there are some incredibly useful tools (voice/sms broadcasting/polling being front in my mind at the moment) that seem to require these kinds of services.

So, I am trying to figure out if we could use our cell phones to replace those VoiP solutions.

One of the first questions I seem to be bumping against is: Can I set up a free PBX (or pay to set up some PBX system that then wouldn’t require me to pay for a subscription)?

Asterisk and FreePBX are opensouce products, not licenses needed, but there are paid modules on FreePBX

Although, in principle SIP allows calls to be made for only the cost of the internet connectivity, in the real world, people do not accept chance SIP calls, but only accept them from a PSTN connection service or the SIP is hidden behind some other service and calls are only accepted from that service

Thank you soooo much!

I have follow up questions, though.

(1) Why don’t people accept “chance SIP calls”?
(2) The services you reference, you are talking about “services” like Skype or Facetime, right?

Can’t the cell phones (and that’s like GSM…I still don’t really understand how most of this works, but I’ve been doing a lot of reading) turn those calls into something people would answer?

  1. Security

  2. Skype doesn’t use SIP internally, but MS Messenger did. I’m not sure about whatsapp.

How do they know a call in insecure?

Seems to me most people I know pretty much answer the phone when they get a call.

When it starts making premium rate outgoing calls, or exploiting vulnerabilities to change the PBX into a bot.

It’s a bit like email. Many businesses don’t accept direct inbound email, but rely on pulling it from an IMAP server, even though that is how SMTP mail was originally designed to work.