Method for accessing a network in electronic system and associated portable device

A method for accessing a network in an electronic system, wherein the electronic system comprises a connectivity service device and a plurality of electronic devices, and the plurality of electronic devices are connected to the connectivity service device, the method comprising:

• connecting a portable device to a connectivity service device in an electronic system when the portable device enters a coverage region of the connectivity service device;
• retrieving the service list from the connectivity service device by the portable device, the service list comprising services available for use in the coverage region, wherein each of the services corresponds to a communications protocol;
• and
• determining a service from the service list to be used for communicating the portable device with a plurality of electronic devices in the coverage region;
• and
• connecting the portable device with the plurality of electronic devices using the predetermined communication protocol of the determined service,
• wherein the portable device, the connectivity service device, and the electronic devices in the coverage region are within a local area network,
• wherein the portable device retrieves the service list from the connectivity service device using a low-power communication protocol in the plurality of predetermined communication protocols,
• wherein the determined service is one of the predetermined communication protocols used by the portable device, and the method further comprises:
• turning off radio frequency circuitry of the portable device which is not associated with the determined service;
• and
• transceiving radio frequency signals from one of the electronic devices through the connectivity service device by the portable device according to the service list.