A method is provided for establishing a communication session with an IMD (101). The method includes an IMD (101) and an external device (201) communicating with one another through a protocol that utilizes a dedicated advertisement channel (406). The IMD (101) periodically transmitting advertisement notices (411, 605, 613) over the dedicated advertisement channel (406) according to the protocol. The advertisement notices (411, 605, 613) being transmitted periodically at an advertisement period (408, 602, 612) over multiple cycles. The external device (201) repeatedly scanning the advertisement channel (406) for select scanning intervals (603) in search of the advertisement notices (411, 605, 613), the scanning operation being repeated periodically at a scan period (601) over the multiple cycles. The advertisement period (408, 602, 612) and the scan period (601) are independent of one another such that the advertisement and scan periods (408, 602, 612； 601) at least partially overlap intermittently after a number of cycles. When the external device (101) detects an advertisement notice (411, 605, 613), a communications link (104) is established between the external device (201) and the IMD (101).
