A computer-implemented method executed by one or more processors for applying network policies to devices based on their current access network, the method comprising: receiving, by a server connected to a public network, a message from a device (132, 142, 144) separate from the server over the public network, the message associated with a source address, wherein the device connects to the public network through a current access network (130, 140) to which the device is connected, wherein the source address of the message is a public IP address assigned to the device (132, 142, 144) when connected to the current access network (130, 140), and wherein the device is assigned an internal IP address for use on the current access network (130, 140) and that is not used outside the current access network (130, 140); determining, by the server, the current access network (130, 140) for the device based on the source address, wherein the current access network (130, 140) is determined by identifying the source address to be associated with a particular source address range of a known access network from a set of known access networks, wherein the known access networks include the current access network (130, 140), wherein the current access network (130, 140) is external to the public network, and the message received from the device (132, 142, 144) on the public network is transmitted by the device (132, 142, 144) over the current access network(130, 140); and applying a network policy to the device based on the determined current access network (130, 140) by sending a message to the device to configure the device according to the network policy, wherein the network policy includes configuration settings including assigning a maximum bandwidth usage parameter to the device. receiving, by a server connected to a public network, a message from a device (132, 142, 144) separate from the server over the public network, the message associated with a source address, wherein the device connects to the public network through a current access network (130, 140) to which the device is connected, wherein the source address of the message is a public IP address assigned to the device (132, 142, 144) when connected to the current access network (130, 140), and wherein the device is assigned an internal IP address for use on the current access network (130, 140) and that is not used outside the current access network (130, 140); determining, by the server, the current access network (130, 140) for the device based on the source address, wherein the current access network (130, 140) is determined by identifying the source address to be associated with a particular source address range of a known access network from a set of known access networks, wherein the known access networks include the current access network (130, 140), wherein the current access network (130, 140) is external to the public network, and the message received from the device (132, 142, 144) on the public network is transmitted by the device (132, 142, 144) over the current access network(130, 140); and applying a network policy to the device based on the determined current access network (130, 140) by sending a message to the device to configure the device according to the network policy, wherein the network policy includes configuration settings including assigning a maximum bandwidth usage parameter to the device.