Abstract:
A method for a terminal to connect to wireless networks in a wireless network system is disclosed. The wireless network system has a plurality of wireless networks, each having a unique identity. The terminal includes a network database for storing a plurality of predetermined identities, a plurality of configuration tables with each associating different predetermined identities to different priorities, and a status pointer representing when or where the terminal operates. The method includes selecting one configuration table according to the status pointer, comparing the identities received by the terminal with the predetermined identities in the selected configuration table, selecting an identity among the matched identities according to the priority associated with the matched predetermined identities, and connecting to the wireless network corresponding to the selected identity.

Description:
BACKGROUND OF INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a method for a terminal connecting to a wireless network, and more particularly, a method of wireless connection to automatically choose an appropriate wireless network from a plurality of available wireless networks according to a location and a time of the terminal.  
           [0003]    2. Description of the Prior Art  
           [0004]    Enormous developments in computer networks enable data and information to spread out rapidly, and advanced technology and knowledge to be communicated efficiently. The development of wireless networks in recent years further enables users to access network resources anytime and anywhere to make information technology more integrated with people&#39;s lives and work.  
           [0005]    One feature of wireless networks is to eliminate the constraint of transmission wires that are found in wired networks. The terminal of the wireless network can wirelessly transmit data by use of electromagnetic waves or infrared radiation to connect to the wireless network for accessing network resources. In the wireless network system, each network server transmits and receives wireless data signals through an access point. Equally, to access the resources and the services of the wireless network, the terminal must be capable of wirelessly transmitting and receiving data signals. Generally, personal computers and notebooks can expand their capabilities to wireless networking by connecting a wireless network card.  
           [0006]    Please refer to FIG. 1. FIG. 1 is a schematic diagram of a typical wireless network  10 . In wireless network  10 , several independent wireless networks  12 A,  12 B,  12 C and  12 D and terminals STA 0 , STA 1 , STA 2  are included. Take the wireless network  12 A for example, it utilizes an access point AP 1  and a server S 1 . The server S 1  mainly controls resource access and network operation of the network  12 A, and the access point AP 1 , capable of wirelessly transmitting and receiving data signals, is electrically connected to the server S 1 . The effective range of the access point AP 1  to transmit and receive wireless signals is marked as a dotted effective range region R 1  in FIG. 1. In the region R 1 , the wireless signal transmitted from the access point AP 1  can be effectively received by terminals in the region R 1 , and vice versa. On the contrary, outside the region R 1 , wireless signals transmitted from the terminals cannot be correctly received by the access point AP 1 . When in effective range R 1 , wireless signals transmitted from the terminals can be received by the access point AP 1  and then transmitted to the server S 1 . Data from the server S 1  can also be wirelessly transmitted to the terminals through the access point AP 1  to allow the terminals to access the network resources of the wireless network  12 A. Equally, wireless network  12 C utilizes a server S 3  and an access point AP 3 , whereas wireless network  12 D utilizes a server S 4  and an access point AP 4  to provide wireless network services.  
           [0007]    A wireless network can broaden its service range by utilizing a plurality of access points. The wireless network  12 B in FIG. 1 is an example of utilizing two access points AP 2   a  and AP 2   b  both electrically connected to the server S 2 . Though separately the overall coverage of effective ranges R 2   a  and R 2   b  served by the access points AP 2   a  and AP 2   b  is limited, a total service area provided by the server S 2  is expanded. For example, if the terminal STA 1  transmits data to the terminal STA 2 , the terminal STA 1  can first transmit a wireless data signal to the access point AP 2   a  for transferring the data to the server S 2 . Then, the server S 2  transfers the data signal to the access point AP 2   b , and finally the access point AP 2   b  wirelessly transmits the data signal to the terminal STA 2 . Therefore, the terminal STA 1  can access the resources of the terminal STA 2  by use of the services provided by the wireless network  12 B.  
           [0008]    Wireless networks need no physical transmission lines, and are thus not limited in size or configuration by transmission lines. Typically, only a few specified terminals can be allowed to access the resources of the wireless network. For example, an internal local wireless network of a company is only open to the employees of the company, and a local wireless network utilized at a home is restricted to the terminals belonging to family members. Currently, many communications companies provide paid wireless network connection service, and only people who have paid a fee can access the wireless network. To achieve the purpose of administrating access and allowing authorized terminals to access network resources, the most basic method employed is identity. Each wireless network has a unique identity, and each terminal authorized by the wireless network has a corresponding identity to the authorizing wireless network. For example, the commonly used wireless network standard IEEE 802.11 has defined a service set identity as an identity of a wireless network. Besides this, identity can also be an Internet protocol address. Take the terminal STA 0  of FIG. 1 as an example to further illustrate the control of resource access between the terminals and the wireless network. In FIG. 1, networks  12 A,  12 B,  12 C and  12 D have the corresponding identities ID 1 , ID 2 , ID 3  and ID 3  separately stored in their respective access points. A resource database DB is stored in the terminal STA 0  to record the related information of which wireless networks the terminal STA 0  can access.  
           [0009]    Please refer to FIG. 2 and FIG. 1. FIG. 2 is a listing of a network database  20  of the resource database DB in the terminal STA 0 . The related data of wireless networks that the terminal  20  can legally access is stored in the network database  20 . Suppose the wireless network  12 A is the internal local wireless network of the company in which the user of the terminal STA 0  works, the wireless network  12 B is a payment network provided by a communications company, and the wireless  12 C is a small local wireless network utilized at the terminal STA 0  user&#39;s home. Therefore, the terminal STA 0  can legally access the network resources of the wireless networks  12 A,  12 B and  12 C, and the related information of these 3 wireless networks is stored in the terminal STA 0 . Please refer to FIG. 2, the network database  20  of the terminal STA 0  includes 3 columns, which are wireless network name, predetermined identity, and accessories, wherein the predetermined identity is the unique identity each wireless network owns. The row L 1  represents the related information of the wireless network  12 A, wherein the wireless network name is company, predetermined identity is ID 1 , accessories are encrypted key K 1 , login ID UN 1 , password Pss 1  among others. Similarly, the row L 2  records that the wireless network  12 B is a payment network, predetermined identity is ID 2 , with key K 2  to encrypt data transmissions, and the terminal STA 0  can login the wireless network  12 B with login ID UN 2 , and password Pss 2 . The row L 3  records that the wireless network  12 C is a family wireless network of the user of the terminal STA 0 , with the predetermined identity being ID 3 , encrypted key being K 3 , login ID being UN 3 , and password being Pss 3 .  
           [0010]    In the prior art, administrating access using identities is described as follows. When the terminal STA 0  is about to connect to the wireless network  12 A utilized in the company, the user has to manually assign the terminal to the wireless network  12 A. The terminal STA 0  then transmits a wireless probe signal with the predetermined identity ID 1  included according to the related information stored in the database  20 . The access point AP 1  of the wireless network  12 A receives the signal with identity ID 1  and then responds with a response signal including the identity ID. When the terminal STA 0  receives the response signal, it then confirms that the access point AP 1  of the wireless network  12 A can successfully receive the wireless signal and proceeds with a further certification sequence establishing wired equivalent privacy. The terminal STA 0  performs associated sequences such as letting the server S 2  know that the terminal STA 0  is communicating through the access point AP 1 . The terminal is then able to login to the server S 1  through UN 1  and Pss 1  as the account and password. Of course, the terminal STA 0  is not legally authorized to access the wireless network  12 D. The terminal STA 0  has no identity ID 4  for the wireless network  12 D, and cannot connect to the wireless network  12 D since no wireless signal including the predetermined identity ID 4  is transmitted.  
           [0011]    If no response signal including identity ID 1  is received for a period of time after the terminal STA 0  transmits the wireless probe signal, the terminal is likely outside the effective range of the wireless network  12 A. As it is shown in FIG. 1, if the terminal STA 0  moves from position P 1  to P 2  and intends to connect to the wireless network  12 A at P 2 , it receives no response from the access point AP 1  since the position P 2  is outside the effective range of the network  12 A. The terminal STA 0  informs the user that the terminal is unable to connect to the wireless network  12 A. Then the user can control the terminal STA 0  to stop attempting to connect to the network  12 A or to retry connecting to another wireless network.  
           [0012]    In the prior art mentioned above, the user must manually control the terminal STA 0  to connect to the desired wireless network. If the position of the terminal STA 0  exceeds the effective range of the wireless network, the user must manually direct the terminal to connect to another wireless network. As discussed above, one advantage of the wireless network is to eliminate the constraints of physical network transmission lines, allowing users to conveniently connect to a network with their terminals anywhere. However, it is difficult for moving users to be aware of which wireless network their terminal is located. So, when the terminal is leaving the service range of a wireless network and reaching another service range of another wireless network, or say, when the terminal is in the overlapping location of two adjacent wireless networks, the user must manually choose a wireless network by the method of trial and error. Though certain network operators provide a configuration table comprising a set of fixed priorities to automatically connect to the wireless network listed in the configuration table, the method is still inconvenient in a varied environment of wireless networks. For example, if the terminal STA 0  is located in the company, it is acceptable to connect to the wireless network  12 A of the company with a high priority. However, when the terminal STA 0  is located at home, then it is much more proper to connect to the wireless network  12 C with a priority higher than that of the wireless network  12 A. However, the prior art configuration table has fixed priorities. Therefore when at home, the user must inconveniently control the terminal to close the configuration table and then manually connect the terminal to the wireless network  12 C.  
         SUMMARY OF INVENTION  
         [0013]    It is therefore a primary objective of the claimed invention to provide a flexible method of automatically connecting to a wireless network to overcome the disadvantages of the prior art.  
           [0014]    According to the claimed invention, a terminal is provided capable of wirelessly transmitting and receiving data through a wireless network system comprising a plurality of wireless networks. The plurality of wireless networks comprises different wireless networks have different identities capable of being transmitted wirelessly by each wireless network.  
           [0015]    According to the claimed invention, the terminal comprises a plurality of distinct sorting pointers each representing a unique priority, a network database for recording a plurality of predetermined identities, a plurality of configuration tables, and a status pointer for representing an operational location and time. Each configuration table corresponds one predetermined identity to one unique sorting pointer and each configuration table has at least a unique predetermined identity that corresponds to a sorting pointer.  
           [0016]    According to the claimed invention, a method receives identities of the plurality of wireless networks via wireless transmission. The method chooses a configuration table from the plurality of configuration tables according to the status pointer and compares the predetermined identity of the chosen configuration table with the identities received, and if any of the plurality of identities received matches the predetermined identity, the method then chooses an identity according to the sorting pointer corresponding to the status pointer. The method wirelessly connects to the wireless network corresponding to the chosen identity.  
           [0017]    It is an advantage of the claimed invention that the plurality of priorities and configuration tables provide time saving and convenient wireless network access to the terminal.  
           [0018]    These and other objectives of the claimed invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0019]    [0019]FIG. 1 is a schematic diagram of a typical wireless network.  
         [0020]    [0020]FIG. 2 is a schematic diagram of a network database of a terminal.  
         [0021]    [0021]FIG. 3 is a schematic diagram of data in a resource database according to the present invention.  
         [0022]    [0022]FIG. 4 is a flowchart diagram of a method of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0023]    The main purpose of the present invention is to provide several sets of priority tables of wireless connection, and to select the most proper priority table referencing a location and time of a terminal. The detailed description below still refers to the wireless network system illustrated in FIG. 1, and the method of the present invention is applied to the terminal STA 0  of FIG. 1.  
         [0024]    Please refer to FIG. 3. As is described in the aforementioned example, the network database  20  in the resources database DB comprises the related information of wireless networks that the terminal STA 0  can legally access. The related information comprises the wireless network ID of the wireless network  12 A,  12 B and  12 C, predetermined identities, and other related information. Additionally, the resources database DB further comprises a status pointer C, a plurality of sorting pointers In 1 -In 4 , and a plurality of configuration tables C 1 -C 4 . Each sorting pointer In 1 -In 4  represents a different priority and each configuration table C 1 -C 4  corresponds different predetermined identities of wireless networks to different sorting pointers In 1 -In 4 . Different configuration tables correspond C 1 -C 4  to different content of the status pointer C. In FIG. 3, the sorting pointer In 1  represents the highest priority, and the sorting pointer In 2  represents the second highest priority, and so on.  
         [0025]    In the present invention, the status pointer C can represent the operating location and time of the terminal STA 0 . Take the configuration table T 1  for example. In order of priority, the configuration table T 1  corresponds to a possible status C 1  of the status pointer C, wherein the configuration table T 1  corresponds the predetermined wireless identity ID 1  of the company to the sorting pointer In 1 , the predetermined wireless identity ID 2  of the paid wireless network to the sorting pointer In 2 , and ID 3  of the family wireless network to the sorting pointer In 3 . Likewise, the configuration table T 2  corresponds to another possible status C 2  of the status pointer C, wherein the configuration table T 2  corresponds the predetermined wireless identity ID 3  of the company to the sorting pointer In 3 , which represents the third highest priority. Similarly, the configuration tables T 3  and T 4  are provided in the same manner as mentioned above.  
         [0026]    Simply speaking, the main purpose of the present invention is for the terminal STA 0  to automatically choose a configuration table from different configuration tables C 1 -C 4  according to different contents of the status pointer C, and proceed to wirelessly connect according to the chosen configuration table. The terminal STA 0  will try to connect to the wireless network with the highest priority in the configuration table. If the terminal STA 0  cannot connect to the wireless network, and it will then try to connect to the wireless network with the second highest priority in the configuration table, and so on. In the operation of the present invention, the status pointer C is directly controlled by a time.  
         [0027]    Generally, computers serving as terminals have a clock to provide the time. The user can setup the status of each configuration table C 1 -C 4  in advance in the database DB. For example, the user is at work during the time from AM 9:00 to PM 5:00, Monday to Friday, so the user can map the contents of the status pointer, C 1 , to these periods of time. During these periods of time, if the user wants to access network resources with the terminal STA 0 , the terminal STA 0  automatically decides to connect to the network assigned by the configuration table T 1  according to the content of the status pointer C. Therefore, the terminal connects to the company wireless network with the identity ID 1  at the highest priority. Similarly, the user brings the terminal STA 0  back home after work, and accordingly, the corresponding status C 2  of the predetermined configuration table T 2  is mapped to the time between PM 7:00 to PM 11:00, Monday to Friday. Therefore, if the terminal attempts to connect to a network during these periods of time, it automatically decides that the configuration table T 2  is adopted to wirelessly connect to the network according to the content of the status pointer C. Finally, the terminal will connect to the family wireless network with identity ID 3  at the highest priority.  
         [0028]    Please refer to FIG. 4, which is a flowchart diagram of operation of the present invention. According to the above-mentioned description, the terminal STA 0  is provided for implementing the operation of the present invention. The flowchart diagram comprises the following steps:  
         [0029]    ( 32 ): Start up.  
         [0030]    The user starts up the wireless network function of the terminal STA 0  and prepares to access the resources of the wireless network.  
         [0031]    ( 34 ):  
         [0032]    Scan services to receive all the identities of the wireless networks. The main purpose of this step is to determine all the wireless networks active in the environment that the terminal is located. Generally speaking, the access point of the wireless network broadcasts a beacon signal containing the identity at a fixed interval. If the terminal receives the beacon signal, the terminal is in a service range and should prepare for connecting to the network. Furthermore, the terminal is capable of actively transmitting a probe containing a certain identity. If the terminal STA 0  receives a response signal containing the identity, the terminal STA 0  is in the effective service range. To sum up, in this step, all the accessible identities are fetched, and the fetched identities may be varied with the location of the terminal STA 0 . If the terminal STA 0  is in the service range of any network, then proceed to step  36 , otherwise, if the terminal STA 0  is not in any service range, then proceed to step  46 .  
         [0033]    ( 36 ):  
         [0034]    After the service is determined, and the identities are fetched, the terminal STA 0  will compare the received identities with the predetermined identities of the network database  20  to decide how many legally accessible wireless networks are available. If a legally accessible wireless network exists, then proceed to step  38 . If not, then proceed to step  48 .  
         [0035]    ( 38 ):  
         [0036]    Choose a corresponding configuration table according to the content of the status pointer C. As mentioned above, the clock of the terminal STA 0  is capable of controlling the content of the status pointer C. In this step, the terminal STA 0  will choose a corresponding configuration table according to the content of the status pointer C. After the step  38  is done, proceed to step  40 .  
         [0037]    ( 40 ):  
         [0038]    In this step, the terminal STA 0  refers to the chosen configuration table to decide which wireless network will be chosen for the terminal STA 0  to connect to. The step further comprises sub-steps of authentication, association according to a key, and wired equivalent privacy by encrypting the data with the key. Of course, the terminal may need a login ID and a password to login to the server.  
         [0039]    ( 42 ):  
         [0040]    After the step  40  is completed, the terminal STA 0  is capable of accessing the services and resources provided by the selected wireless network.  
         [0041]    ( 44 ):  
         [0042]    During the service sequence of the wireless network, the terminal STA 0  continuously monitors the wireless signal from the corresponding access point to see if the connection is still active. If the wireless network is disconnected, then proceed to step  46 .  
         [0043]    ( 46 ):  
         [0044]    The terminal STA 0  is located in an environment with no wireless network available, or the wireless network has just been disconnected. In order to reconnect to the wireless network, the operation will proceed to step  34  for iteration until a network connection is established.  
         [0045]    ( 48 ):  
         [0046]    The terminal STA 0  has received the identities of the wireless networks, but found no identities identical to the identities stored in the network database  20 . If the user decides to reconnect to the wireless networks, then the operation proceeds to step  50 . If not, the operation proceeds to step  46 .  
         [0047]    ( 50 ):  
         [0048]    The user decided to connect to a wireless networks having an identity not in the database DB. The terminal STA 0  can refresh the configuration tables C 1 -C 4  and network database  20  to add in the identity of this network. If the terminal STA 0  receives a plurality of identities not identical to the predetermined identities, it establishes a new configuration table temporarily using a random priority list to sort the new identities, or simply appends the new identities into an existing configuration table. After this step is finished, the operation proceeds to step  40 .  
         [0049]    In practical operation, the configuration tables C 1 -C 4  and network database  20  can be administrated by a front-end software application to allow users convenient establishing, editing, and refreshing of the configuration tables C 1 -C 4  and the network database  20 . A wireless network function driver is active in the terminal STA 0  and can execute the operation as illustrated by the flowchart diagram in FIG. 4. Besides controlling the status pointer C by time, the present invention allows the user to choose status pointers using a simple query program. For example, when the user is connecting to a network with the terminal STA 0 , the query program asks the user which location the user is in, and then sets the status pointer C accordingly. The present invention gives the user more flexibility in both location and time in setting the priorities of wireless network connections.  
         [0050]    In summary, the present invention utilizes a plurality of configuration tables, and each of the configuration tables utilizes different connection priorities to different wireless networks. The terminal can automatically choose a specified configuration table according to the contents of the status pointers, and then connect to the wireless network according to the priorities of the configuration table. Compared with the prior art&#39;s lack of flexibility, the present invention can dynamically adapt to different wireless network environments, thus enabling users more efficient and convenient access to network resources.  
         [0051]    Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.