A network gateway device (10) for determining information related to a designated data transmission rate for a wireless link includes at least one means for communicating (12) for communicating with a wireless modem means (200). The network gateway device (10) includes a means for controlling (14) configured for obtaining information related to an instantaneous data transmission capacity of the wireless link via the at least one means for communicating (12). The means for controlling (14) is configured for determining the information related to the designated data transmission rate based on the information related to the instantaneous data transmission capacity of the wireless link. The designated data transmission rate is lower than an average data transmission capacity of the wireless link. An availability of the designated data transmission rate over the wireless link is higher than an availability of the average data transmission capacity over the wireless link.