Scalable wireless messaging system

• US 20070191033A1
• Filed: 02/16/2006
• Published: 08/16/2007
• Est. Priority Date: 02/16/2006
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Softwired AG
• Inventors: Marais, Charl
• Granted Patent: US 7,512,408 B2
• Time in Patent Office: Days
• US Class Current: 455/466
• CPC Class Codes: H04L 67/04 specially adapted for terminals or networks with limited capabilities; specially adapted for terminal portability
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 67/288 Distributed intermediate devices, i.e. intermediate devices for interaction with other intermediate devices on the same level
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/59 Providing operational support to end devices by off-loading in the network or by emulation, e.g. when they are unavailable
• CPC Class Codes: H04W 4/12 Messaging; Mailboxes; Announcements
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 76/19 Connection re-establishment
• CPC Class Codes: H04W 88/16 Gateway arrangements
• CPC Class Codes: H04W 88/182 Network node acting on behalf of an other network entity, e.g. proxy

Abstract

A method for operating a wireless messaging system, the messaging system being configured to comprise a plurality of mobile wireless clients (1, 1′, 1″), a core messaging system (7) and at least two gateway processes or gateways (5, 5′, 5″) acting as proxies on behalf of the clients (1, 1′, 1″), the method comprising, in order for a client (1) to establish a connection with one of the gateways (5, 5′, 5″), a two phase connect procedure with the steps of,

• • the client (1) maintaining a list of access points, each access point defining an address at one of the gateways (5, 5′, 5″);
  • the client (1) sending, over a wireless bearer (4, 4′, 4″), a phase one connection request to one of the access points;
  • the gateway (5, 5′, 5″) that is addressed by the phase one connection request, sending, in response to the phase one connection request, over a wireless bearer (4, 4′, 4″), a list of connect points to the client (1), each connect point defining an address at one of the gateways (5, 5′, 5″);
  • the client (1) sending, over a wireless bearer (4, 4′, 4″), a phase two connection request to at least one of the connect points; and
  • the gateway (5, 5′, 5″) that is addressed by the phase two connection request responding to the phase two connection request, and the client (1) establishing a connection with the gateway (5, 5′, 5″) specified by said connect point.

Claims

1. A method for operating a wireless messaging system, the messaging system being configured to comprise a plurality of mobile wireless clients, a core messaging system and at least two gateway processes or gateways, the gateways acting as proxies on behalf of the clients and in the course of normal operation of the messaging system maintaining sessions by performing the steps of,

the gateways receiving inbound messages from the clients over a wireless bearer using a wireless protocol and forwarding said inbound messages to the core messaging system over a connection using a wirebound protocol;

the gateways receiving outbound messages from the core messaging system over a connection using a wirebound protocol and forwarding said outbound messages to the clients over connections using a wireless protocol;

the method comprising, in order for a client to establish a connection with one of the gateways, a two phase connect procedure with the steps of,

the client maintaining a list of access points, each access point defining an address at one of the gateways;

the client sending, over a wireless connection, a phase one connection request to one of the access points;

the gateway that is addressed by the phase one connection request, sending, in response to the phase one connection request, over a wireless bearer, a list of connect points to the client, each connect point defining an address at one of the gateways;

the client sending, over a wireless bearer, a phase two connection request to at least one of the connect points; and

the gateway that is addressed by the phase two connection request responding to the phase two connection request, and the client establishing a connection with the gateway specified by said connect point.

2. The method of claim 1, further comprising the step of

the client, if a phase one connection request is unsuccessful, sending a further phase one connection request to a further access point selected from the list of access points.

3. The method of claim 1, further comprising the step of

the list of connect points being an ordered list, and the client, if the preceding phase two connection request is unsuccessful, sending a further phase two connection request to the next connect point in the current list of connect points.

4. The method of claim 3, further comprising the step of

a load balancing unit creating the list of connect points in response to a first connection request, the order of the list being determined as to balance the load between gateways.

5. The method of claim 4, further comprising the step of

the load balancing unit determining a load parameter characterizing, for each of the available gateways, a current load, and the load balancing unit ordering the list of connect points in ascending order according to the load parameter of the gateways associated with the connect points.

6. The method of claim 1, wherein the access points are defined as a HTTP request.

7. The method of claim 1, wherein the connect points are defined by a protocol, an address, and a port to be used.

8. The method of claim 1, the messaging system further comprising a common data store configured to store a session context, which session context comprises the status of a session established between the core messaging system and one of the clients, a state of the client connection associated with the session, and a session identifier, the method comprising the steps of

a first gateway maintaining a session;

the first gateway updating and maintaining, for said session, an associated session context in the common data store;

the first gateway no longer maintaining said session;

a second gateway retrieving, for said session, the associated session context from the common data store;

the second gateway maintaining said session.

9. The method of claim 8, comprising the steps of

a gateway receiving a phase two connection request from a client, the connection request comprising a session identifier;

the gateway initiating a lock operation on the session context in the data store associated with said session identifier;

if the lock operation succeeds, the gateway locking the session context, thus preventing other gateways from accessing the session context;

if the lock operation does not succeed, the gateway informing the client that the connection request is rejected;

if no session with said session identifier exists, the gateway creating in the data store, an entry for the session context with said session identifier.

10. The method of claim 9, comprising the steps of

a gateway, after receiving a phase two connection request, determining that another gateway, which according to the session context owns the session identified by the connection request, is not operational;

said first gateway breaking the lock and taking ownership of the session.

11. The method of claim 1, comprising the steps of

a gateway receiving a phase two connection request from a client, the connection request comprising a session identifier;

the gateway initiating a lock operation on the session context in the local memory associated with said session identifier;

if the lock operation succeeds, the gateway locking the session context, thus preventing other acceptor threads triggered by concurrent connect requests for the same session identifier from accessing the session context;

if the lock operation does not succeed, the gateway informing the client that the connection request is rejected;

if no session with said session identifier exists, the gateway creating in a local memory section a session context with said session identifier.

14. A computer program for operating a wireless messaging system, which computer program is loadable and executable on a data processing unit in a gateway computer, the messaging system being configured to comprise a plurality of mobile wireless clients, a core messaging system and at least two gateway processes or gateways for providing message forwarding from the clients to the messaging server and vice versa, and which computer program, when being executed on one the gateway computers, performs the steps of the method of claim 1.

12. A wireless messaging system, the messaging system being configured to comprise a plurality of mobile wireless clients, a core messaging system and at least two gateway processes or gateways, the gateways acting as proxies on behalf of the clients and comprising a client session manager for, in the course of normal operation of the messaging system, maintaining client sessions by

receiving inbound messages from the clients over wireless bearers using a wireless protocol and forwarding said inbound messages to the core messaging system over a connection using a wirebound protocol;

receiving outbound messages from the core messaging system over a connection using a wirebound protocol and forwarding said outbound messages to the clients over a wireless bearer using a wireless protocol;

the wireless messaging system further comprising, in order for a client to establish a connection with one of the gateways, a distributed logic for implementing a two phase connect procedure, said distributed logic comprising;

in the client, a client library providing an application program interface for, among others, accepting, access points, each access point defining an address at one of the gateways;

in the client, the client library comprising a phase one routine for sending, over a wireless bearer, a phase one connection request to one of the access points;

in the gateway that is addressed by the phase one connection request, a servlet for sending, in response to the phase one connection request, over a wireless bearer, a list of connect points to the client, each connect point defining an address at one of the gateways;

the client library also comprising a phase two routine for sending, over a wireless bearer, a phase two connection request to at least one of the connect points; and

the gateway that is addressed by the phase two connection request comprising a response logic for responding to the phase two connection request, and for establishing a connection between the client and the gateway.

13. The system of claim 12, further comprising a load balancing unit for creating the list of connect points in response to a first connection request, the order of the list being determined as to balance the load between gateways