What 'level' registrar will a person contact to register their AOR details?

In the context of registering Address of Record (AOR) details, the correct level registrar to contact is typically referred to as Tier 2. This designation is significant because Tier 2 registrars play a crucial role in managing registrations related to Session Initiation Protocol (SIP) services.

Tier 2 registrars are often more closely aligned with SIP service providers and can directly handle interactions concerning user registrations for AORs. They facilitate the necessary processes to ensure that the details are correctly recorded and maintained within the SIP network, enabling seamless communication and service delivery.

The other tiers, such as Tier 1, Tier 3, and Tier 4, may handle different aspects of telecom or internet services but do not specifically focus on managing AOR registrations as efficiently as Tier 2. This structure allows for a system where Tier 2 registrars are specifically equipped to support the unique needs associated with SIP-based communication, making them the appropriate point of contact for registering AOR details.