SIP Setup

[AMOCO]

1:Can someone elaborate on what SIP is?
2:Are there any free SIP servers?
3:Is SIP hard to setup?
4:Which is a better,Using a free call/text app or Using SIP?
5:With SIP will I be able to use my existing mobile phone number?

I want to setup a free call/text Wi-Fi to use at home.
Right now I'm using an app called Viber.

 

[AMOCO]

1:Can someone elaborate on what SIP is?
2:Are there any free SIP servers?
3:Is SIP hard to setup?
4:Which is a better,Using a free call/text app or Using SIP?
5:With SIP will I be able to use my existing mobile phone number?

I want to setup a free call/text Wi-Fi to use at home.
Right now I'm using an app called Viber.

Never mind the OP.
I got it setup,Used https://www.getonsip.com to get a SIP account.
It connects,But how can you tell if it's working? or If I'm just using my Boost Mobile service plan.

 

[AMOCO]

Bump