##### 3.2.2.5.5 Phone Contact with IP Address Contact Confirming the Applicant's control over the IP Address by calling the IP Address Contact’s phone number and obtaining a response confirming the Applicant's request for validation of the IP Address. The CA MUST place the call to a phone number identified by the IP Address Registration Authority as the IP Address Contact. Each phone call SHALL be made to a single number. In the event that someone other than an IP Address Contact is reached, the CA MAY request to be transferred to the IP Address Contact. In the event of reaching voicemail, the CA may leave the Random Value and the IP Address(es) being validated. The Random Value MUST be returned to the CA to approve the request. The Random Value SHALL remain valid for use in a confirming response for no more than 30 days from its creation. The CPS MAY specify a shorter validity period for Random Values.