Title of Invention

METHOD OF AUTHENTICATING AND REGISTERING A MOBILE STATION IN THIRD GENERATION PARTNERSHIP PROJECT 2 (3GPP2) NETWORKS

Abstract

The present invention relates generally to communication systems, and particularly, to a low latency method and system to support secure mobility in a data communications network in AAA based infrastructures. More particularly this invention is applicable to mobile stations moving in 3GPP2 networks. The invention explains a system and method for decreasing MIP registration time in 3GGP2 network comprising the steps of: establishing a new PPP session with a new PDSN when MS is moved from one PDSN to another PDSN; sending MIP Reg Req to PDSN after receiving Agent Advertisement from new PDSN; sending MIP Reg Req encapsulated in Auth Req by PDSN to foreign AAA server which in turn sends to home AAA server;sending MIP Reg Req to HA by home AAA server if MS is legitimate;directly sending Auth Response by home AAA server if MS is not legitimate;sending MIP Reg Rep to home AAA server in response to MIP Reg Req by HA;sending MIP Reg Rep encapsulated in Auth Response to foreign AAA server by Home AAA server which gets in turn delivers to PDSN; and delivering the MIP Reg Rep to MS by PDSN.

Full Text

FIELD OF THE INVENTION The present invention relates generally to communication systems, and particularly, to a low latency method and system to support secure mobility in a data communications network in AAA based infrastructures. More particularly this invention is applicable to mobile stations moving in 3GPP2 networks. DESCRIPTION OF THE RELATED ART IP connects the various networks and sub networks which make up the internet by defining, among other things, the rules and procedures which govern the way IP data packets are routed from a source node to a destination node. To ensure that IP data packets are correctly routed, every node is assigned an IP address, wherein the IP address defines a fixed network location associated with a correspondent node. While IP adequately handles the routing of data between fixed network nodes, it does not adequately handle the routing of IP data packets to and/or from mobile nodes. In order to solve that, the Mobile Internet Protocol (i.e., Mobile IP) was designed to specifically handle the routing of IP data packets to and/or from mobile nodes (i.e., mobile terminals which frequently change their point-of-attachment to the Internet). Moreover, Mobile IP was designed to handle the routing of IP data packets to and/or from mobile nodes without significantly interrupting on-going communications and without requiring mobile nodes to restart applications. Thus Mobile IP ensures correct routing of packets to mobile node as the mobile node changes the point of attachment to the internet. The [cdma2000] describes the procedures for Mobile IP operation for IPv4 in 3GPP2 networks. This procedure allows a mobile node to move from one link to another without much network problems. Therefore the handing off between Radio Networks connected to different Packet Data Serving Nodes can be easily accomplished by maintaining the transport and higher level connections. Using mobile IP, a mobile node registers with its home agent (HA) each time it changes care-of-address. It is important to authenticate registration requests, as they inform the HA about the MN's current Care-of-address, which is the destination for the tunneled packets from the home network. In this process, after receiving MIP registration request from MS, PDSN uses the AAA to authenticate the user before sending the MIP registration request to HA, i.e. authentication and registration are executed serially. Due to the serial way of the authentication and registration procedures, it will increase handoff latency and may not be suitable for real time applications. For authenticating MS, Auth Request (authentication request) packet will be sent to home RADIUS server (home network), after getting the reply, registration (with HA) procedures are started from PDSN. So, this procedure causes more latency. SUMMARY OF THE INVENTION This method and system proposes a way to achieve low latency during handoff in 3GPP2 networks. The invention allows greater support for real time services on a mobile network by minimizing the period of time when the mobile node is unable to send or receive IP packets due to the delay in Mobile IP registration process. In short this method reduces the time taken for registration procedures by piggybacking registration information along with authentication request. Accordingly this invention explains a method for decreasing MIP registration time in 3GGP2 network comprising the steps of: (a) establishing a new PPP session with a new PDSN when MS is moved from one PDSN to another PDSN; (b) sending MIP Reg Req to PDSN after receiving Agent Advertisement from new PDSN; (c) sending MIP Reg Req encapsulated in Auth Req by PDSN to foreign AAA server which in turn sends to home AAA server; (d) sending MIP Reg Req to HA by home AAA server if MS is legitimate; (e) directly sending Auth Response by home AAA server if MS is not legitimate; (f) sending MIP Reg Rep to home AAA server in response to MIP Reg Req by HA; (g) sending MIP Reg Rep encapsulated in Auth Response to foreign AAA server by Home AAA server which gets in turn delivers to PDSN; and (h) delivering the MIP Reg Rep to MS by PDSN. The PDSN does not provide the MIP service for the MS if the said MS is not legitimate. The said method involves saving round trip time from PDSN to home network by parallel execution of authentication and registration procedures .77ie said method is implemented in MS, PDSN, RADIUS client, RADIUS server and HA.The home AAA server delays Auth Response till it receives MIP Reg Rep. Accordingly this invention also explains a system for decreasing MIP registration time in 3GGP2 network comprising: (a) means for establishing a new PPP session with a new PDSN when MS is moved from one PDSN to another PDSN; (b) means for sending MIP Reg Req to PDSN after receiving Agent Advertisement from new PDSN; (c) means for sending MIP Reg Req encapsulated in Auth Req by PDSN to foreign AAA server which in turn sends to home AAA server; (d) means for sending MIP Reg Req to HA by home AAA server if MS is legitimate; (e) means for directly sending Auth Response by home AAA server if MS is not legitimate; (f) means for sending MIP Reg Rep to home AAA server in response to MIP Reg Req by HA; (g) means for sending MIP Reg Rep encapsulated in Auth Response to foreign AAA server by Home AAA server which gets in turn delivers to PDSN; and (h) means for delivering the MIP Reg Rep to MS by PDSN. These and other objects, features and advantages of the present invention will become more readily apparent from the detailed description taken in conjunction with the drawings and the claims. BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS Figure 1 shows the operation of the prior art method proposed in 3GPP2 for Mobile IP service. Figure 2 shows a possible scenario where this invented method is applicable. Figure 3 shows the operation of the method disclosed in this invention. DETAILED DESCRIPTION OF THE INVENTION The preferred embodiments of the present invention will now be explained with reference to the accompanying drawings. It should be understood however that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. The following description and drawings are not to be construed as limiting the invention and numerous specific details are described to provide a thorough understanding of the present invention, as the basis for the claims and as a basis for teaching one skilled in the art how to make and/or use the invention. However in certain instances, well-known or conventional details are not described in order not to unnecessarily obscure the present invention in detail. Mobile computing has greatly increased in popularity over the past several years, due to the large advances in miniaturization. It is now widely recognized that using IP as the foundation for next generation cellular networks makes strong economic and technical sense, since it takes the advantage of the ubiquitous installed IP infrastructure, capitalizes on the IETF standardization process, and benefits from both the existing and emerging IP-related technologies and services. However, because mobility is an essential characteristic of cellular networks, mobility needs to be handled at IP layer. lETF's Mobile IP [MIPv4] provides a standard solution for wide area mobility at the IP layer. Mobile IPv4 allows a Mobile Node (MN) to change its point of attachment to the Internet while maintaining its fixed home address. Packets directed to the home address are intercepted by a Home Agent (HA), encapsulated in a tunnel, and forwarded to the MN at its current point of attachment. Optionally, a Foreign Agent (FA) may be deployed at this point of attachment, which can serve as the tunnel endpoint and may also provide access control for the visited network link. In this role, the FA has to authenticate each MN that may attach to it, whether the MN is from the same or a different administrative domain. The FA has to verify that the MN is authorized to attach and use resources in the foreign domain. The FA must provide information to the home administrative domain about the resources used by the MN while it is attached in the foreign domain, before providing Mobile IP service. Handoff latency should be as less as possible for some real world applications. The primary object of this invention is to decrease the time taken for authentication and registration procedures (Mobile IP), when MS is moving between PDSNs. Figure 1 shows the operation of the prior art method proposed in 3GPP2 for Mobile IP service. The various steps involved in the method can be explained as follows. MS sends MIP Reg Req after receiving agent advertisement in new subnet. After receiving MIP Reg Req, PDSN authenticates MS. PDSN sends Auth Req to foreign AAA server, which in turn forwards to home AAA server. Home AAA server sends the Auth Response to foreign AAA server, and it forwards to PDSN. If the MS is legitimate, PDSN sends the MIP Reg Req to HA. HA sends the Reg Reply in response to Reg. Req and PDSN will send the Reg Reply to MS. Authentication and Registration procedures are executed serially. Figure 2 shows a possible scenario where this invented method is applicable. PDSN acts as IP point of attachment. PDSN also acts as FA and RADIUS client. PPP is used as link layer between MS and PDSN. Home AAA and Visited AAA represent the AAA server in the home network and visited network respectively. AAA broker server may be involved in the support of AAA messaging and functions between the visited AAA and home AAA. AAA servers and PDSN (acting as AAA client) are involved in authenticating the MN and PDSN (acting as FA) and HA are involved in MIP procedures along with MN. Operation of the Invention The invention proposes a procedure for the parallel execution of authentication and registration procedures to decrease the handoff latency. The proposed method will be implemented in MS, PDSN, RADIUS client, RADIUS server and HA. Figure 3 shows the operation of the method disclosed in this invention. The following is the step-by-step operation of the invention: 1. When MS is moved from one PDSN to another PDSN, it will establish new PPP session with new PDSN (if MS is using MIPv4) 2. After receiving Agent Advertisement from new PDSN, MS sends MIP Reg Req (Registration Request) to PDSN (which is acting as FA). 3. PDSN (which is also acting as RADIUS client) sends MIP Reg Req encapsulated in Auth Req (authentication request) to foreign AAA server which in turn sends to home AAA server. (In the existing 3gpp2 standard, PDSN sends only auth req) 4. If MS is legitimate, then home AAA server sends MIP Reg Req to HA 5. If MS is not legitimate, home AAA server directly sends Auth Response (without sending MIP Reg Req to HA) and the PDSN will not provide the MIP service for this MS. 6. HA sends MIP Reg Rep (Registration Reply) to home AAA server in response to MIP Reg Req. 7. Home AAA server sends MIP Reg Rep encapsulated in Auth Response to foreign AAA server, which in turn delivers to PDSN. 8. PDSN delivers the MIP Reg Rep to MS. The above-presented description is of the best mode contemplated for carrying out the present invention. The manner and process of making and using it is in such a full, clear, concise and exact terms as to enable to any person skilled in the art to which it pertains to make and use this invention. New embodiments in particular, which also lie within the scope of the invention can be created, in which different details of the different examples can in a purposeful way be combined with one another. This invention is however, susceptible to modifications and alternate constructions from that disclosed above which are fully equivalent. Consequently, it is not the intention to limit this invention to the particular embodiment disclosed. On the contrary, the intention is to cover all modifications and alternate constructions coming within the spirit and scope of the invention as generally expressed by the following claims which particularly point out and distinctly claim the subject matter of the invention. GLOSSARY OF TERMS AND DEFINITIONS THEREOF AAA (h) -Authentication, Authorisation, and Accounting home AAA (f) -Authentication, Authorisation, and Accounting foreign FA - Foreign Agent HA - Home Agent MS - Mobile Station PCF - Packet Control Function PDSN - Packet Data Serving Node Reg - Registration Rep - Reply Req - Request RN - Radio Network WE CLAIM 1. A method for decreasing MIP registration time in 3GGP2 network comprising the steps of: (a) establishing a new PPP session with a new PDSN when MS is moved from one PDSN to another PDSN; (b) sending MIP Reg Req to PDSN after receiving Agent Advertisement from new PDSN; (c) sending MIP Reg Req encapsulated in Auth Req by PDSN to foreign AAA server which in turn sends to home AAA server; (d) sending MIP Reg Req to HA by home AAA server if MS is legitimate; (e) directly sending Auth Response by home AAA server if MS is not legitimate; (f) sending MIP Reg Rep to home AAA server in response to MIP Reg Req by HA; (g) sending MIP Reg Rep encapsulated in Auth Response to foreign AAA server by Home AAA server which gets in turn delivers to PDSN; and (h) delivering the MIP Reg Rep to MS by PDSN. 2. A method as claimed in claim 1 wherein the PDSN does not provide the MIP service for the MS if the said MS is not legitimate. 3. A method as claimed in claim 1 wherein the said method involves saving round trip time from PDSN to home network by parallel execution of authentication and registration procedures. 4. A method as claimed in claim 1 wherein the said method is implemented in MS, PDSN, RADIUS client, RADIUS server and HA. 5. A method as claimed in claim 1 wherein the home AAA server delays Auth Response till it receives MIP Reg Rep. 6. A system for decreasing MIP registration time in 3GGP2 network comprising: (a) means for establishing a new PPP session with a new PDSN when MS is moved from one PDSN to another PDSN; (b) means for sending MIP Reg Req to PDSN after receiving Agent Advertisement from new PDSN; (c) means for sending MIP Reg Req encapsulated in Auth Req by PDSN to foreign AAA server which in turn sends to home AAA server; (d) means for sending MIP Reg Req to HA by home AAA server if MS is legitimate; (e) means for directly sending Auth Response by home AAA server if MS is not legitimate; (f) means for sending MIP Reg Rep to home AAA server in response to MIP Reg Req by HA; (g) means for sending MIP Reg Rep encapsulated in Auth Response to foreign AAA server by Home AAA server which gets in turn delivers to PDSN; and (h) means for delivering the MIP Reg Rep to MS by PDSN. 7. A system as claimed in claim 6 wherein the PDSN does not provide the MIP service for the MS if the said MS is not legitimate. 8. A system as claimed in claim 6 wherein the said method involves saving round trip time from PDSN to home network by parallel execution of authentication and registration procedures. 9. A system as claimed in claim 6 wherein the said method is implemented in MS, PDSN, RADIUS client RADIUS server and HA. 10. A system as claimed in claim 6 wherein the home AAA server delays Auth Response till it receives MIP Reg Rep. 11. A method for decreasing MIP registration time in 3GGP2 network substantially described particularly with reference to the accompanying drawings. 12. A system for decreasing MIP registration time in 3GGP2 network substantially described particularly with reference to the accompanying drawings.

Documents:

1953-CHE-2005 AMENDED CLAIMS 18-01-2013.pdf

1953-CHE-2005 AMENDED PAGES OF SPECIFICATION 18-01-2013.pdf

1953-CHE-2005 EXAMINATION REPORT REPLY RECEIVED 18-01-2013.pdf

1953-CHE-2005 OTHER PATENT DOCUMENT 18-01-2013.pdf

1953-CHE-2005 FORM-1 18-01-2013.pdf

1953-CHE-2005 FORM-13 18-01-2013.pdf

1953-CHE-2005 FORM-13 19-06-2006.pdf

1953-CHE-2005 FORM-5 18-01-2013.pdf

1953-CHE-2005 FORM.13 18-01-2013.pdf

1953-CHE-2005 OTHERS 18-01-2013.pdf

1953-CHE-2005 POWER OF ATTORNEY 18-01-2013.pdf

1953-che-2005-abstract.pdf

1953-che-2005-claims.pdf

1953-che-2005-correspondnece-others.pdf

1953-che-2005-description(complete).pdf

1953-che-2005-drawings.pdf

1953-che-2005-form 1.pdf

1953-che-2005-form 26.pdf