Femto cell local breakout with PPP proxy

• US 8,305,963 B1
• Filed: 08/06/2009
• Issued: 11/06/2012
• Est. Priority Date: 08/06/2009
• Status: Active Grant

• Current Assignee: T-Mobile Innovations LLC (Deutsche Telekom AG)
• Original Assignee: Sprint Communications Company LP (Deutsche Telekom AG)
• Inventors: Breau, Jeremy R., Oh, Daesik
• Primary Examiner(s): Nooristany, Sulaiman
• Application Number:
  US12/536,648
• Time in Patent Office: 1,188 Days
• Field of Search: 370328-329
• US Class Current: 370/328
• CPC Class Codes: H04W 76/12 Setup of transport tunnels
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

Methods are provided for facilitating local communication between wireless devices at a femto cell without passing communication to a network infrastructure, routing data packets to devices connected to a femto cell, and eliminating a need to send data to a home agent when two devices are connected to the same femto cell. When mobile devices are in a femto cell zone, it is not necessary to send payload information to a core network including a packet data serving node and a home agent. A femto cell local breakout with a PPP proxy can be used to handle the payload information locally. The femto cell local breakout with PPP proxy stores the mobile devices and IP addresses. So, when one mobile device in the femto cell zone sends payload information to another mobile device, the femto cell routes the payload information to the other mobile device in the femto cell zone.

Claims

1. A method for facilitating local communications between wireless devices at a femto cell without passing communication to a network infrastructure, comprising:

receiving a request for a data session at the femto cell from a first mobile device, wherein receiving the request comprises receiving a source internet protocol (IP) address associated with the first mobile device and a destination IP address associated with a second mobile device;

creating a first point-to-point protocol (PPP) tunnel between the femto cell and the first mobile device;

wherein creating the first PPP tunnel comprises binding the femto cell and the first mobile device together in a communication session;

analyzing the request to capture the destination IP address;

analyzing a mapping table in the femto cell to determine if the destination IP address is in the mapping table;

if the destination IP address is in the mapping table, creating a second PPP tunnel between the femto cell and the second mobile device;

wherein creating the second PPP tunnel comprises removing an original PPP tunnel that the second mobile device has with the femto cell and establishing the second PPP tunnel between the second mobile device and the femto cell and routing the data session between the first mobile device and the second mobile device using the first PPP tunnel and the second PPP tunnel without passing the data session to the network infrastructure wherein the network infrastructure includes at least one of a home agent and a packet data serving node (PDSN); and

if the destination IP address is not in the mapping table, but the second mobile device is connected to the femto cell, creating an outbound PPP tunnel between the femto cell and the network infrastructure and routing the data session from the first mobile device to the network infrastructure and then back through the femto cell to the second mobile device.

2. The method of claim 1, further comprising creating the mapping table in the femto cell by monitoring traffic between the femto cell and the network infrastructure, adding an entry in the mapping table for each mobile device that connects to the femto cell, and removing the entry from the mapping table for each mobile device that is not connected to the femto cell.

3. The method of claim 2, further comprising receiving the entry to populate the mapping table from the at least one of the home agent and the PDSN.

4. The method of claim 2, further comprising receiving the entry to populate the mapping table from each mobile device.

5. A method for routing data packets to devices connected to a femto cell, comprising:

receiving a data packet in a data session into a femto cell from a source mobile device, wherein receiving the data packet comprises receiving an internet protocol (IP) address of the source mobile device and an IP address of the target mobile device in a header of the data packet and receiving a payload in a body of the data packet;

wherein the data session comprises binding the femto cell and the first mobile device together in a first PPP tunnel communication session;

determining a target mobile device is connected to the femto cell, wherein determining the target mobile device is connected to the femto cell comprises checking for the IP address of the target mobile device in a mapping table in the femto cell and determining that the IP address of the target mobile device is found in the mapping table;

routing the data packet to the target mobile device without sending the data packet to a home agent or a packet data serving node (PDSN), wherein routing the data packet to the target mobile device comprises encapsulating the data packet into a point-to-point protocol (PPP) proxy;

wherein encapsulating the data packet into a point-to-point (PPP) proxy comprises removing an original PPP tunnel that the target mobile device has with the femto cell and establishing second PPP tunnel between the target mobile device and the femto cell; and

determining the target mobile device is connected to the femto cell, wherein determining the target mobile device is connected to the femto cell comprises checking for the IP address of the target mobile device in a mapping table in the femto cell and determining that the IP address of the target mobile device is not found in the mapping table, creating an outbound PPP tunnel between the femto cell and the network infrastructure and routing the data session from the source mobile device to the network infrastructure and then back through the femto cell to the target mobile device.

6. A method for eliminating a need to send a data session to a network infrastructure when two devices are connected to same femto cell comprising:

parsing messages that pass through the femto cell from mobile devices and the network infrastructure wherein the network infrastructure includes at least a home agent and a packet data serving node (PDSN);

building a mapping table in the femto cell that contains information about the mobile devices that are connected to the femto cell wherein building the mapping table comprises adding an internet protocol (IP) address and a point-to-point protocol (PPP) tunnel information of a mobile device to the mapping table;

receiving a packet in the femto cell from a first mobile device destined for a second mobile device wherein the packet includes a source IP address of the first mobile device, a target IP address of the second mobile device, and a first payload, and wherein at least the target IP address and the first payload are encapsulated into a first PPP tunnel between the first mobile device and the femto cell, wherein the first PPP tunnel comprises binding the femto cell and the first mobile device together in a communication session;

checking for the target IP address in the received packet from the first mobile device;

determining that the target IP address of the second mobile device is found in the mapping table which indicates the second mobile device is connected to the femto cell;

encapsulating the at least the target IP address and the first payload into a second PPP tunnel between the second mobile device and the femto cell, wherein the second PPP tunnel comprises removing an original PPP tunnel that the second mobile device has with the femto cell and establishing the second PPP tunnel between the second mobile device and the femto cell;

delivering the at least the target IP address and the first payload to the second mobile device without sending the data packet to the home agent or the packet data serving node (PDSN); and

determining that the target IP address of the second mobile device is not found in the mapping table, but the second mobile device is connected to the femto cell, creating an outbound PPP tunnel between the femto cell and the network infrastructure and routing the data session from the first mobile device to the network infrastructure and then back through the femto cell to the second mobile device.

7. The method of claim 6, further comprising allocating a memory in the femto cell and storing the mapping table in the memory.

8. The method of claim 7, wherein the second PPP binds the femto cell and the second mobile device into another communication session.

9. The method of claim 7, further comprising receiving the IP address of the mobile device to populate the mapping table from the home agent.

10. The method of claim 7, further comprising receiving the IP address of the mobile device to populate the mapping table from the mobile device.

11. The method of claim 7, further comprising removing the target IP address from the mapping table which indicates the second mobile device is not connected to the femto cell.