L2 method for a wireless station to locate and associate with a wireless network in communication with a Mobile IP agent

A method in a wireless station having a wireless network device, the method operating at the link layer (L2) of a multi-layer communication protocol that includes the link layer and a network layer (L3), the method comprising:

• prior to the station being associated with a wireless network, wirelessly receiving L2 data units transmitted from one or more wireless access point (APs) of one or more wireless networks;
• prior to the station being associated with a wireless network, analyzing said received L2 data units to identify the AP and to ascertain whether any of said L2 data units contains an L3 advertisement from a mobility agent,
• prior to the station being associated with a wireless network, if it is ascertained that an L2 data unit contains an advertisement from a mobility agent, reporting the advertisement to L3 at the station as if the station was associated with the network of the AP that transmitted the L2 data unit containing the L3 advertisement;
• in the case that L3 at the station responds to the L3 advertisement by passing to the station's L2 an L3 response to the L3 advertisement addressed to the mobility agent that sent the L3 advertisement, accepting the L3 response from L3 at the station prior to the station being associated with a wireless network, and
• after said analyzing L2-data units, reporting to L3, and accepting the L3 response, associating the station to the AP that transmitted the L2 data unit containing the L3 advertisement,
• such that the wireless station associates with an AP that is in communication with a mobility agent.

In a wireless station registered with a first mobility agent and associated with a first wireless network that is in communication with the first mobility agent, the station having a first wireless network device providing a link-layer (L2) interface to the first wireless network, a method operating at the link layer (L2) of a multi-layer network protocol, a method comprising:

• determining that a re-association is necessary;
• selecting for re-associating a wireless network that the station could hear, the selecting according to one or more re-association criteria at least one of which uses L3 information, the L3 information provided in a stored database of information gathered at the station by an L2 data gathering process;
• and
• re-associating with the selected wireless network,
• wherein the L2 data gathering process includes:
• wirelessly receiving L2 data units transmitted from one or more wireless access point (APs) of one or more wireless networks that the station can hear while the station is not necessarily associated with any wireless network;
• and
• examining the received L2 data units.

In a wireless station having a wireless network device, the device capable of providing a link-layer (L2) interface to a wireless network, an apparatus operating at the link layer (L2) of a multi-layer network protocol, the apparatus comprising:

• means for wirelessly receiving L2 data units transmitted from one or more wireless access point (APs) of one or more wireless networks that the station can hear, the receiving being prior to the station being associated with a wireless network via the wireless network device;
• and
• means for gathering information about the received L2 data units, including L2 information and L3 information,
• the L3 information gathered at L2 including whether an AP is sending one or more L3 packets from one or more mobility agents,
• such that the station may associate with a wireless network that is in communication with a mobility agent.

In a wireless station registered with a first mobility agent and associated with a first wireless network that is in communication with the first mobility agent, the station having a first wireless network device providing a link-layer (L2) interface to the first wireless network, an apparatus operating at the link layer (L2) of a multi-layer network protocol, an apparatus comprising:

• means for determining that a re-association is necessary;
• means for selecting for re-associating a wireless network that the station could hear, the selecting means selecting according to one or more re-association criteria at least one of which uses L3 information, the L3 information provided in a stored database of information gathered at the station by an L2 data gathering process;
• and
• means for re-associating with the selected wireless network,
• wherein the L2 data gathering process includes:
• wirelessly receiving L2 data units transmitted from one or more wireless access point (APs) of one or more wireless networks that the station can hear while the station is not necessarily associated with any wireless network;
• and
• examining the received L2 data units.

A wireless station comprising:

• a wireless network device capable of providing a link-layer (L2) interface to a wireless network, the wireless network device to wirelessly receive L2 data units transmitted from one or more wireless access point (APs) of one or more wireless networks that the station can hear, the receiving being prior to the station being associated with a wireless network via the wireless network device;
• and
• a processor coupled to the wireless network device to gather information about the received L2 data units, including L2 information and L3 information;
• the L3 information gathered at L2 including whether an AP is sending one or more L3 packets from one or more mobility agents,
• such that the station may associate with a wireless network that is in communication with a mobility agent.