Anyone in this community can explain how Silence Unknown Callers feature works on iPhone

Also "will block any *unknown contact " - HOW?

An unknown contact or caller is anyone that is not in your contacts list.

How does it "block" an incoming call?

It doesn't. This has already been explained twice above. Please re-read those responses. The unknown caller goes straight to voicemail. You never hear the phone ring.

does the phone send back any response to the caller.

The unknown caller goes directly to voicemail. Nothing else happens.

Maybe if you could stop using the word "block", things would be come more clear. An unknown or spam caller will go straight to voicemail. You will never hear the phone ring. That's it.

Questions that have already been answered will not be answered again.

Hello sappco!

It really is very simple.

“Silence Unknown Callers” will block any *unknown contact from calling you.

*To learn how this feature determines if a contact is “unknown,” please read the excerpt from this article below:

“… phone numbers that you've never been in contact with and don’t have saved in your contacts list. If you’ve previously texted with someone using their phone number or if a person has shared their phone number with you in an email, a phone call from that number will go through.”

I hope this is helpful. Good Luck!

Does it use a "silent ring tone"?

No, the phone does not ring at all, the unknown caller goes direct to your voicemail and the caller appears in the Recents call list

Does the phone ring at least once before the call is "rejected"?

No, the phone does not ring at all, the unknown caller goes direct to your voicemail and the caller appears in the Recents call list

sappco wrote:

This article does NOT answer my question Does it use a "silent ring tone"? the article provides just a flat dummy description what happens on the surface... I don't need it... I am trying to find a meaningful answer.

NO. It does not use a "silent ring tone". The phone will not ring or notify you in any way that a call is coming it. It will immediately reject the call.

Also "will block any *unknown contact " - HOW? How does it "block" an incoming call? does the phone send back any response to the caller...? How, How, how???

No It does not send anything back to the caller. It rejects the call completely, sending it to your voicemail, if you have voicemail on your cellular plan.

“Does it use a "silent ring tone?” I am unaware of such a feature. Either one hears a ringtone, or they don’t, in which case the ringtone is nonexistent. If you mean “Does it use Vibrate?,” no, it does not. For that would mean the call goes through, which it does not. The call is blocked.

”How does it block an incoming call?” This question takes us into an area of this subject, in which I am not very familiar. I’m referring to the “going deep” explanation of why this works.

“does the phone send back any response to the caller...?” I’m assuming only your voicemail greeting.

It simply rejects the call. If you have voice mail on your cellular plan, the call will drop directly to voicemail.

It does not use a "silent ring tone".

Your phone will not ring at all. The caller may hear a 'ring', but most likely not. If they due, it's cause by the delay in interconnects between carriers.