Version caching mechanism

• US 20040215794A1
• Filed: 04/11/2003
• Published: 10/28/2004
• Est. Priority Date: 04/11/2003
• Status: Active Grant

• Current Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Lauer, Bryan A.
• Granted Patent: US 7,490,152 B2
• Time in Patent Office: Days
• US Class Current: 709/230
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04W 76/12 Setup of transport tunnels
• CPC Class Codes: H04W 76/18 Management of setup rejection or failure
• CPC Class Codes: H04W 84/04 Large scale networks; Deep hierarchical networks

Abstract

A protocol identifier, such as, a GTP version identifier, is automatically cached in association with device contact information. Setup latency is reduced for subsequent connections. For instance, the cache indicates that a GGSN only supports GTPV₀. An SGSN attempts to create a PDP context with the GGSN using GTPV₀ without first trying GTPV₁. If the cache does not include a version identifier for an APN IP address, the SGSN tries to create a context with a first version (e.g., GTPV₁) and, if necessary, a second version (e.g., GTPV₀). An identifier associated with the successful protocol is stored in the cache in association with the contact information (e.g., APN or APN IP address). Freshness of cached information is assured. For example, when all tunnels associated with an APN IP address are torn down, a flush timer is started. If the timer expires, the cache entry is removed.

Claims

1. A method for caching a supported protocol of a device, the method comprising:

receiving a first request to establish a connection with the device, the request being associated with contact information related to the device;

using the contact information as a key or index into a protocol cache;

attempting to establish the connection with the device using a protocol associated with a previously stored protocol identifier if the previously stored protocol identifier is stored in association with the contact information;

attempting to establish the connection with the device with a first protocol if the previously stored protocol identifier is not stored in association with the contact information;

storing a first protocol identifier in a protocol cache in association with the contact information if the attempt to establish the connection with the device with the first protocol was successful;

attempting to establish a connection with the device with a second protocol if the attempt to establish the connection with the device with the first protocol was not successful; and

,

storing a second protocol identifier in the protocol cache in association with the contact information if the attempt to establish the connection with the device with the second protocol was successful and the attempt to establish the connection with the device with the first protocol was not successful.

2. The method for caching a supported protocol of claim 1 further comprising:

removing the association of the previously stored, first or second protocol identifier with the contact information upon the expiration of a flush timer.

3. The method for caching a supported protocol of claim 2 further comprising:

starting the flush timer when all connections associated with the contact information between a system having the cache and the device torn down.

4. The method for caching a supported protocol of claim 1 further comprising:

removing the association of the previously stored identifier with the contact information if the attempt to establish communication with the device using a protocol associated with the previously stored protocol identifier is unsuccessful.

5. The method for caching a supported protocol of claim 1 wherein receiving a request to establish communication with the device comprises:

receiving an Activate PDP Context Request message.

6. The method for caching a supported protocol of claim 1 wherein receiving a request to establish communication with the device, the request being associated with contact information related to the device comprises:

receiving an Activate PDP Context Request message, the Activate PDP Context Request message including information identifying a requestor;

accessing a database with the information identifying the requester;

retrieving the contact information from the database.

7. The method for caching a supported protocol of claim 1 wherein receiving a request to establish communication with the device, the request being associated with contact information related to the device comprises:

receiving an Activate PDP Context Request message, the Activate PDP Context Request message being associated with information identifying a requester;

accessing a home location register with the information identifying the requestor;

retrieving the contact information from the home location register or with information supplied by the home location register.

8. The method for caching a supported protocol of claim 1 wherein receiving a request to establish communication with the device, the request being associated with contact information related to the device comprises:

receiving an Activate PDP Context Request message including an APN.

9. The method for caching a supported protocol of claim 1 wherein storing the first or second protocol identifier in the protocol cache in association with the contact information comprises:

storing a first or second GTP version identifier in a GTP version cache in association with an APN or an APN IP address.

10. A method for caching a GTP version of a GPRS support node, the method comprising:

receiving a GTP tunnel setup request message associated with an APN or APN IP address;

determining if a previously stored GTP version entry associated with the APN or APN IP address exists in a GTP version cache table;

if the previously stored GTP version entry does not exist;

attempting to establish a connection with the GPRS support node with a first version of GTP;

determining if the attempt to establish a connection with the GPRS support node with a first version of GTP was successful;

if the attempt to establish a connection with the GPRS support node with a first version of GTP was successful;

storing a first GTP version identifier in the GTP version cache table in association with the APN or APN IP address;

if the attempt to establish a connection with the GPRS support node with the first version of GTP was not successful;

attempting to establish a connection with the GPRS support node with a second version of GTP;

determining if the attempt to establish a connection with the GPRS support node with the second version of GTP was successful; and

if the attempt to establish a connection with the GPRS support node with a second version of GTP was successful;

storing a second GTP version identifier in the GTP version cache table in association with the APN or APN IP address.

11. The method for caching a GTP version of a GPRS support node of claim 10 further comprising:

monitoring a status of tunnels associated with the APN or APN IP address;

starting a timer when all monitored tunnels associated with the APN or APN IP address are torn down; and

flushing the previously stored, first or second GTP version identifier cache entry associated with the APN or APN IP address when the timer expires.

12. The method for caching a GTP version of a GPRS support node of claim 11 further comprising:

removing the timer if a new tunnel is set up in association with the APN or APN IP address before the timer expires.

13. The method for caching a GTP version of a GPRS support node of claim 10 wherein receiving a first GTP tunnel setup request message comprises:

receiving a GTP Activate PDP Context Request message associated with an APN; and

,.

resolving the APN into an APN IP address.

14. The method for caching a GTP version of a GPRS support node of claim 11 wherein monitoring the status of tunnels associated with the APN or APN IP address comprises:

incrementing a counter associated with the APN or APN IP address each time a PDP context is set up in association with the APN or APN IP address; and

,

decrementing the counter associated with the APN or APN IP address each time a PDP context associated with the APN or APN IP is torn down.

15. The method for caching a GTP version of a GPRS support node of claim 14 wherein starting the timer when all monitored tunnels associated with the APN or APN IP address are torn down comprises:

starting the timer when the counter associated with the APN or APN IP address has a zero value.

16. The method for caching a GTP version of a GPRS support node of claim 10 further comprising:

attempting to establish a connection with the GPRS support node with a version of GTP associated with the previously stored GTP version; and

flushing the previously stored GTP version entry associated with the APN or APN IP address if the attempt to establish a connection with the GPRS support node with the version of GTP associated with the previously stored GTP version was not successful.

17. The method for caching a GTP version of a GPRS support node of claim 16 further comprising:

attempting to establish the connection with the GPRS support node with the first version of GTP;

determining if the attempt to establish the connection with the GPRS support node with the first version of GTP was successful;

if the attempt to establish the connection with the GPRS support node with the first version of GTP was successful;

storing a first GTP version identifier in the GTP version cache table in association with the APN or APN IP address;

if the attempt to establish a connection with the GPRS support node with the first version of GTP was not successful;

attempting to establish the connection with the GPRS support node with a second version of GTP;

determining if the attempt to establish a connection with the GPRS support node with the second version of GTP was successful; and

if the attempt to establish a connection with the GPRS support node with a second version of GTP was successful;

storing a second GTP version identifier in the GTP version cache table in association with the APN or APN IP address.

18. The method for caching a GTP version of a GPRS support node, of claim 10 wherein attempting to establish a connection with the GPRS support node with a first version of GTP comprises:

attempting to establish a connection with the GPRS support node with GTP_V1.

19. The method for caching a GTP version of a GPRS support node of claim 10 wherein attempting to establish a connection with the GPRS support node with a second version of GTP comprises:

attempting to establish a connection with the GPRS support node with GTP_V0.

20. An SGSN operative to cache a GTP version associated with a GGSN, the SGSN comprising:

a GTP version cache including a plurality of GTP version identifiers in association with a respective plurality of APNs or APN IP addresses and a respective plurality of context counts;

means for receiving a GTP tunnel setup request message associated with an APN or an APN IP address;

means for attempting to establish a connection with the GPRS support node with a version of GTP associated with the previously stored GTP version identifier;

means for incrementing a context count when a context is successfully set up using an APN or APN IP address and a GTP version associated with a GTP version identifier stored in the GTP version cache in association with the APN IP address; and

,

means for decrementing the context count when the context associated with the APN or APN IP address and the GTP version associated with the GTP version identifier stored in the GTP version cache in association with the APN or APN IP address, is torn down.

21. The SGSN of claim 20 wherein the GTP version cache further comprises:

a plurality of respective timer values in association with the respective plurality of APNs or APN IP addresses and the respective plurality of context counts;

means for updating a respective timer value according to a passage of time;

means for starting the means for updating the respective timer value when a respective context count has a zero value; and

,

means for removing an association between a respective GTP version identifier and a respective APN or APN IP address when the respective timer value reaches a predetermined value.

22. The SGSN of claim 21 further comprising:

means for stopping the means for updating the respective timer value before the respective timer value reaches the predetermined value if the respective context count is incremented above the zero value.

23. The SGSN of claim 20 further comprising:

means for removing an association between a respective GTP version identifier and a respective APN or APN IP address if an attempt to establish a connection with the GPRS support node with a version of GTP associated with the respective GTP version identifier fails.

24. The SGSN of claim 20 further comprising:

means for attempting to establish a connection with the GPRS support node with a trial version of GTP; and

,

means for storing a trial GTP version identifier in the GTP version cache in association with the APN or APN IP address if the attempt to establish the connection with the GPRS support node with the trial version of GTP is successful.

25. The SGSN of claim 24 wherein the means for attempting to establish a connection with the GPRS support node with a trial version of GTP comprises:

means for attempting to establish a connection with the GPRS support node with GTP_V1.

26. The SGSN of claim 24 wherein the means for attempting to establish a connection with the GPRS support node with a trial version of GTP comprises:

means for attempting to establish a connection with the GPRS support node with GTP_V0.