A post by senior product manager Jason Leznek on the Microsoft Windows Vista team blog stating that Vista RTM features a “sleep” function for WiFi connections raised concerns among laptop users. The pre-RC1 version is set to “Medium Power” if a laptop operates on battery power and this default setting carries a “sleep” feature, which enables the adaptor to switch to low power mode. This function alerts wireless access points to queue up packets and transmit them in bigger chunks to allow the adoptor longer resting time between updates. Microsoft later adopted changes by shifting the default wireless network settings to “Maximum Performance” after beta testers found that the router failed to accurately identify clients when they are in sleep mode, thus leading to packet loss. The change can be enabled by the user or by the OEM prior to the shipment of the computer. Despite the modification, problems of lower battery life could still occur if access points do not support the 802.11 sleep function, which was only implemented recently.