System and method for movement detection and congestion response for transport layer protocol

Abstract

A system, apparatus, and method for determining network capacity and managing network congestion in response to a change in an end-to-end communication path between sender and receiver hosts. A receiver mobility notification is provided by the receiver host to the sender host. The sender host determines whether the receiver host has moved between networks or sub-networks using the receiver mobility notification. If the sender host determines that the receiver host has moved from one network/subnet to another network/subnet, a congestion state at the sender host is reset to correspond to the new end-to-end communication path established between the sender host and the receiver host in the new subnet.

1 . A method comprising:
 receiving at a first device a mobility notification originating from a second device;   determining at the first device, using the received mobility notification, whether the second device has moved from a first subnet to a second subnet; and   in response to determining that the second device has moved to a second subnet, resetting a congestion state at the first device to correspond to a new communication path between the first device and the second device.   
     
     
         2 . The method of  claim 1 , wherein receiving the mobility notification comprises receiving the mobility notification at the first device via a transport layer protocol. 
     
     
         3 . The method of  claim 2 , wherein receiving the mobility notification via a transport layer protocol comprises receiving the mobility notification via a connection-oriented transport layer protocol. 
     
     
         4 . The method of  claim 2 , wherein receiving the mobility notification at the first device via a transport layer protocol comprises receiving the mobility notification via one of a Transport Control Protocol (TCP) and a Stream Control Transmission Protocol (SCTP). 
     
     
         5 . The method of  claim 1 , wherein receiving the mobility notification comprises receiving a mobility flag in a header field of segments received by the first device from the second device. 
     
     
         6 . The method of  claim 5 , wherein receiving a mobility flag in a header field comprises receiving a mobility bit having a first state indicating no movement by the second device from the first subnet to the second subnet, and having a second state indicating movement by the second device from the first subnet to the second subnet. 
     
     
         7 . The method of  claim 1 , wherein determining at the first device whether the second device has moved from a first subnet to a second subnet comprises comparing the received mobility notification to a stored state of the mobility notification. 
     
     
         8 . The method of  claim 1 , wherein receiving a mobility notification originating from the second device comprises receiving the mobility notification from the second device in one or more acknowledgment segments that acknowledge receipt of a data segment previously sent from the first device to the second device. 
     
     
         9 . A method comprising:
 at a receiver device, receiving data originating from a sending device via an original end-to-end communication path;   providing from the receiver device one or more mobility notifications indicating that the receiver device itself has moved from a first subnet to a second subnet, the mobility notifications enabling the sending device to reset a congestion state to correspond to a new end-to-end communication path between the sender device and the moved receiver device; and   at the receiver device, receiving further data originating from the sending device via the new end-to-end communication path in accordance with the reset congestion state.   
     
     
         10 . The method of  claim 9 , further comprising determining, at the receiver device, whether the receiver device has moved from the first subnet to the second subnet resulting in establishment of the new end-to-end communication path between the receiver device and the sending device. 
     
     
         11 . The method of  claim 10 , wherein determining whether the receiver device has moved comprises the receiver device monitoring location contents of a destination memory module, comparing the location contents to locally stored location data, and determining whether the receiver device has moved as a function of the comparison of the location contents and the locally stored location data. 
     
     
         12 . The method of  claim 9 , wherein providing the one or more mobility notifications comprises providing a first mobility notification while the receiver device is located in the first subnet, and providing a second mobility notification distinguishable from the first mobility notification upon relocation of the receiver device from the first subnet to the second subnet. 
     
     
         13 . The method of  claim 9 , wherein providing the one or more mobility notifications comprises providing the one or more mobility notifications from the receiving device via a transport layer protocol. 
     
     
         14 . The method of  claim 9 , wherein providing the one or more mobility notifications comprises providing the one or more mobility notifications from the receiving device via a mobility flag in a header field of segments transmitted via a transport layer protocol. 
     
     
         15 . The method of  claim 9 , wherein providing the one or more mobility notifications comprises providing the one or more mobility notifications from the receiver device in one or more acknowledgment packets that acknowledge receipt of data segments received at the receiving device from the sending device. 
     
     
         16 . A method for determining network capacity and managing network congestion in response to a change in an end-to-end communication path between a sender host and a receiver host, the method comprising:
 determining whether the receiver host has moved from a first subnet to a second subnet, wherein the receiver host movement results in a new end-to-end communication path between the sender and receiver hosts at the transport layer;   notifying the sender host of the receiver host's movement via a transport layer protocol;   detecting the movement of the receiver host at the sender host using the notification; and   resetting a congestion state at the sender host to accommodate the new communication path.   
     
     
         17 . An apparatus comprising:
 a transmitter to wirelessly transmit data addressed to a recipient device;   a receiver to receive at least one mobility notification originating from the recipient device that represents whether a change in the recipient device's current location has occurred;   storage storing location data representative of the recipient device's last known location;   a compare module coupled to receive the mobility notification and the stored location data, and configured to output a result indicating whether the mobility notification differs from the stored location data; and   a processor configured to analyze the result, and to reset a congestion state for further wireless data transmissions from the transmitter addressed to the recipient device if the result indicates that the mobility notification differs from the stored location data.   
     
     
         18 . The apparatus as in  claim 17 , wherein the compare module is integrated with the processor.