FAQ - SIP endpoint identifier (EPID)

SipProvider.<id>.InstanceCoding 

0 = Disabled

1 = Adds an 'epid' tag to the 'From'header

https://wiki.unify.com/images/3/3e/OpenScape_Voice_V6%2C_SIP_to_Phones_Interface_Manual.pdf

5.14.6 epid parameter
The client shall use the MAC address of the phone as the EPID as this uniquely
identifies the device and is persistent over a reboot of the phone.
The format for the epid will be an 8 character ASCI string encoded as follows
where "XX" is a two character string identifying the manufacturer of the device,
and "SC" is reserved for use by Siemens devices.
The client shall include the epid in the From: header of every request generated
by the phone (e.g. REGISTER, INVITE, SUBSCRIBE etc.) for non-keyset lines
and for keyset primary lines, i.e. epid shall not be included for calls from keyset
secondary lines.
Example:
From:15615299502<sip:15615299502@10.232.3.110:5061>;tag=0470c66c
d6;epid=SCBCC441

Example: From: <sip:1014@192.168.178.210>;tag=dd6d1a91-800f-4037-ac55-322665c29b7b;epid=9e74a599

2 = Add '+sip.instance' to 'Contact' header

(according to https://datatracker.ietf.org/doc/html/rfc5626#section-4.1 ) that uniquely identifies the device.

Software version 2.46.0 or higher is needed.

Example: Contact: <sip:1020@192.168.178.197:5060>;reg-id=1;+sip.instance="<urn:uuid:00000000-0000-1000-8000-589EC62904F3>"