SIP Registration using mac authentication

Hi Team,

I am very new for Asterisk and using Asterisk 16.1 with CentOS7.6. i want to register my sip phone using that mac address for some security of pbx.
So is this possible? If yes , Please guide me . . . .

Put the MAC rather than the primary extension number in sip.conf or pjsip.conf. This is already best practice, but few people do it as they like the convenience of Dial(SIP/${EXTEN}).

Note that conflating extensions and devices (sometimes called directory numbers and equipment numbers) is so ingrained into FreePBX that it might be difficult there.

check about provisioning method

Still i am not able to resolve or secure my extensions.
can you please brief me, how do i configure and where i need to change so it works.