Preserving HTTP sessions in heterogeneous wireless environments

Abstract

Wireless internet in the in-vehicle environment is an evolving reality that reflects the gradual convergence of wireless and internet technologies. The present invention provides an application layer system that makes wireless internet access adaptive to dynamically changing heterogeneous network environments, by stressing carrier-independence and access transparency. To achieve these objectives, the present invention provides the following features: HTTP session continuity and automatic HTTP failure recovery; network environment awareness and application-level preemptive handoff based on bandwidth capacity.

1 . A proxy for use with a user device operating in a heterogeneous wireless network environment, said proxy comprising: 
 means for determining that said user device is in an area of overlap by different networks within said environment; and    means for handing off said user device from a first network to a second network.    
     
     
         2 . A proxy according to  claim 1 , wherein said determining means combines both event-driven and polling-based schemes for detecting changes in network conditions.  
     
     
         3 . A proxy according to  claim 1 , wherein said second network operates at a higher bandwidth than said first network.  
     
     
         4 . A proxy according to  claim 1 , further comprising means to track an ongoing session with said user device.  
     
     
         5 . A proxy according to  claim 4 , wherein said tracking means is a byte counter.  
     
     
         6 . A proxy according to  claim 4 , wherein said session is a HTTP session.  
     
     
         7 . A proxy according to  claim 4 , wherein said session is a SNMP session, a POP3 session, an IMAP session, or a streaming session.  
     
     
         8 . A method of handing off a user device from a first network to a second network, said method comprising: 
 establishing a session on said user device with said first network;    determining that said user device is in an area where said first network and said second network overlap; and    handing off said user device from said first network to said second network.    
     
     
         9 . A method according to  claim 8 , wherein said determining step comprises: 
 using an event-driven scheme to detect network events;    using a polling-based scheme to collect general network conditions; and    combining results from said event-driven scheme and said polling-based scheme.    
     
     
         10 . A method according to  claim 8 , wherein said second network operates at a higher bandwidth than said first network.  
     
     
         11 . A method according to  claim 8 , further including the step of tracking the byte count of said session.  
     
     
         12 . A method according to  claim 8 , wherein said session is a HTTP session.  
     
     
         13 . A proxy according to  claim 8 , wherein said session is a SNMP session, a POP3 session, an IMAP session, or a streaming session.  
     
     
         14 . An architecture for use in a heterogeneous wireless network environment, said architecture comprising: 
 a user device having an installed web browser;    a web server;    a proxy interposed between said web browser and said web server; and    an information gateway interposed between said proxy and said web server.    
     
     
         15 . An architecture according to  claim 14 , wherein said proxy includes 
 means for determining that said user device is in an area of overlap by different networks within said environment; and    means for handing off said user device from a first network to a second network.    
     
     
         16 . An architecture according to  claim 15 , wherein said determining means combines both event-driven and polling-based schemes for detecting changes in network conditions.  
     
     
         17 . An architecture according to  claim 15 , wherein said second network operates at a higher bandwidth than said first network.  
     
     
         18 . An architecture according to  claim 15 , wherein said proxy includes means to track an ongoing session with said user device.  
     
     
         19 . An architecture according to  claim 18 , wherein said tracking means is a byte counter.  
     
     
         20 . An architecture according to  claim 18 , wherein said proxy and said information gateway communicate information from said tracking means so that upon handoff from said first network to said second network, file loading can begin at the point that file loading was stopped because of said handoff.