Title of Invention

A METHOD FOR FACILITATING FASTER L2 HANDOVER

Abstract The present invention in general relates to Mobile IPv6. In particular, it deals with making Fast MIPv6 even faster by using faster L2 Handover. More particularly the present invention relates to using fast mipv6 to trigger faster 12 handover of a mobile node from an Initial Access Point associated with a Previous Access Router to a neighboring Access Point associated with a Next Access Router comprising the steps of: at Previous Access Router: (a1) sending neighboring Access Point id in the Handover Initiate message; (a2) getting neighboring Access Point's IPv6 Address from the Handover Acknowledge message; (a3) transferring neighboring Access Point's and said mobile node's IPv6 Address to Initial Access Point; at Mobile Node: (b1) sending neighboring Access Point id in the Fast Binding Update message; at Next Access Router: (d) receiving neighboring Access Point id from the Handover Initiate message; (c2) sending neighboring Access Point's IPv6 Address in the Handover Acknowledge message; at Initial Access Point: (d1) getting neighboring Access Point's IPv6 address from Previous Access Router; (d2) sending mobile node specific parameters directly to neighboring Access Point for prior allocation of resource at neighboring Access Point for mobile node; at the neighboring Access Point: (e1) allocating prior resource for mobile node after receiving message from initial Access Point.
Full Text FIELD OF THE INVENTION
The present invention in general relates to Mobile IPv6. In particular, it deals with making Fast MIPv6 even faster by using faster L2 Handover. More particularly the present invention relates to using fast mipv6 to trigger faster 12 handover.
DESCRIPTION OF RELATED ART
The Normal Fast MIPv6 technique [FMIPV6] involves delegating the future prefix to MN in advance. This reduces the hand-off latency, when MN moves from PAR to NAR.
OPERATION OF RELATED ART (REFER TO FIGURE 1)
A Fast MIPv6 [FMIPv6] handover(MN moving from AP2 to AP3) consists of the following messages:
1. MN sends RtSolPr to PAR to find out about neighboring ARs.
2. MN receives a PrRtAdv from PAR containing one or more [AP-ID, AR-Info] tuples.
3. The MN sends FBU to the PAR.
4. The PAR sends HI message to the NAR.
5. The NAR sends HAck message to the PAR.

6. The PAR sends FBAck message to the new link. The FBAck is also optionally sent on the previous link if the FBU was sent from there.
7. The MN sends FNA to the NAR after attaching to it.
LIMITATIONS
During Handover, when MN moves from AP2 to AP3, AP3 has no prior information about MN. Hence, the normal "Association" [IEEE] process between AP3 and MN will lead to L2 hand-off latency.
SUMMARY OF THE INVENTION
The present invention deals with utilizing Fast MIPv6 messages during Predictive Handover to reduce L2 hand-off latency.
Accordingly, this invention explains a method of using fast MIPV6 to trigger faster L2 handover of a mobile node from an Initial Access Point associated with a Previous Access Router to a neighboring Access Point associated with a Next Access Router comprising the steps of:
At Previous Access Router:
(a1) sending neighboring Access Point id in the Handover Initiate message;
(a2) getting neighboring Access Point's IPv6 Address from the Handover

Acknowledge message;
(a3) transferring neighboring Access Point's and said mobile node's IPv6 Address
to Initial Access Point;
At Mobile Node:
(b1) sending neighboring Access Point id in the Fast Binding Update message;
At Next Access Router:
(d) receiving neighboring Access Point id from the Handover Initiate message;
(c2) sending neighboring Access Point's IPv6 Address in the Handover Acknowledge message;
At Initial Access Point:
(d1) getting neighboring Access Point's IPv6 address from Previous Access
Router;
(d2) sending mobile node specific parameters directly to neighboring Access Point
for prior allocation of resource at neighboring Access Point for mobile node;
At the neighboring Access Point:
(e1) allocating prior resource for mobile node after receiving message from initial
Access Point.
Initially mobile node does a scan and gets neighboring Access Point ID. The

mobile node sends a RtSolPr to Previous Access Router and Previous Access Router sends PrRtAdv to mobile node. Mobile node sends a Fast Binding Update message to Previous Access Router where neighboring Access Point id is included in the Fast Binding Update. Previous Access Router sends Handover Initiate message with a Context Transfer and neighboring Access Point id. Next Access Router sends Handover Acknowledge message with neighboring Access Point's IPv6 Address. Previous Access Router informs Initial Access Point regarding mobile node trying to move to neighboring Access Point and neighboring Access Point's IPv6 address is sent to Initial Access Point. Initial Access Point directly contacts neighboring Access Point through its IPv6 Address and sends Resource Allocation Parameters specific to mobile node. Previous Access Router sends Fast Binding Acknowledgement to mobile node and the said mobile node does a handover.
These and other objects, features and advantages of the present invention will become more apparent from the ensuing detailed description of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 depicts a network hand-over of a Mobile Node (MN) from the Previous Access Router (PAR) to the Next Access Router (NAR). PAR advertises prefix 3ff1:: /64. NAR advertises prefix 4ff1:: /64. MN is initially attached to Access Point 2 (AP2). MN does a scan of the neighboring Access Points. FMIPv6 messages

are exchanged between MN and PAR, PAR and NAR. Finally MN does a handover from AP2 to AP3. Hence MN's IPv6 Care of Address changes from 3ff1::15 to 4ff1::15.
Figure 2 depicts the operation of the method disclosed in this invention. It depicts control and data message flow. The following is the step-by-step operation of the invention depicted in Figure 2.
1. MN does a scan and gets AP3-id.
2. MN sends a RtSolPr to PAR.
3. PAR sends PrRtAdv to MN.
4. MN sends a FBU to PAR. AP3-id is included in the FBU.
5. PAR sends HI with the Context Transfer [1] and AP3-id.
6. NAR sends Hack with AP3's IPv6 Address.
7. PAR informs AP2 regarding MN trying to move to AP3. AP3's IPv6 address is sent to AP2.
8. AP2 directly contacts AP3 through its IPv6 Address and sends Resource Allocation Parameters specific to MN.
9. PAR sends FBAck to MN.
10. MN can do a Handover now.
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 IPv6 enables a Mobile Node to maintain its connectivity to the Internet when moving from one Access Router to another, a process referred to as handover. During handover, there is a period when the Mobile Node is unable to send or receive packets due to both link switching delay and IP protocol operations. This "handover latency" resulting from standard Mobile IPv6 procedures, namely movement detection, new Care of Address configuration and Binding Update, is often unacceptable to real-time traffic such as Voice over IP. Reducing the handover latency could be beneficial to non real-time, throughput-sensitive applications as well. The MIPv6 procedures related latency is handled in [FMIPV6]. The primary objective of this invention is to reduce the link-switching latency( L2 Handover Latency) during network handover.
The invention satisfies the following criteria:
• L2 hand-off latency is reduced.
• Interoperable with existing standards.

Simple and easily deployable.
OPERATION OF THE INVENTION
In this invention, we propose a method to reduce L2 Hand-off latency when a Mobile Node undergoes network handover. Figure 1 depicts an example scenario where this method is helpful.
The following is the step-by-step operation of the invention: (Refer to Figure. 1 and Figure.2)
1. MN does a scan and gets AP3-id.
2. MN sends a RtSolPr to PAR.
3. PAR sends PrRtAdv to MN.
4. MN sends a FBU to PAR. AP3-id is included in the FBU.
5. PAR sends HI with the Context Transfer [1] and AP3-id.
6. NAR sends Hack with AP3*s IPv6 Address.
7. PAR informs AP2 regarding MN trying to move to AP3. AP3's IPv6 address is sent to AP2.
8. AP2 directly contacts AP3 through its IPv6 Address and sends Resource Allocation Parameters specific to MN.
9. PAR sends FBAck to MN.
10. MN can do a Handover now.
ADVANTAGES

a. This method reduces loss of packets for the on-going session at MN when
MN undergoes handover.
b. This method reduces L2 Hand-off latency for MN.
c. This method requires no re-configuration or support of v6 routers.
d. This method is very easy to implement and requires very minimal
implementation changes to existing equipments.
It will also be obvious to those skilled in the art that other control methods and apparatuses can be derived from the combinations of the various methods and apparatuses of the present invention as taught by the description and the accompanying drawings and these shall also be considered within the scope of the present invention. Further, description of such combinations and variations is therefore omitted above. It should also be noted that the host for storing the applications include but not limited to a microchip, microprocessor, handheld communication device, computer, rendering device or a multi function device.
Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are possible and are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart there from.

REFERENCES
[FMIPV6]
Rajeev Koodli, "Fast Handovers for Mobile IPv6" ,draft-ietf-mipshop-fast-mipv6, October,
2004. [802.11]
Mobile IPv6 Fast Handovers for 802.11 Networks draft-ietf-mipshop-80211fh [IEEE]
802.11F :IEEE Trial-Use Recommended Practice for Multi-Vendor Access Point Interoperability
via an Inter- Acess Point Protocol Across Distribution Systems Supporting IEEE 802.11 Operation. [MIPv6]
D. Johnson, C. Perkins and J. Arkko, "Mobility Support in IPv6" , RFC 3775, June 2004. [IPv6]
Deering S. and R. Hinden, "Internet Protocol, Version 6 (IPv6)
Specification", RFC 2460, December 1998.

GLOSSARY OF TERMS AND DEFINITIONS THEREOF
MN: Mobile Node
FMIPv6: Fast Mobile IPv6
RtSolPr: Router Solicitation for Proxy Advertisement
PrRtAdv: Proxy Router Advertisement
HI: Handover Initiate
Hack: Handover Acknowledge
FBU: Fast Binding Update
FBAck: Fast Binding Acknowledgement
FNA: Fast Neighbor Advertisement
AP: Access Point
PAR: Previous Access Router
NAR: Next Access Router





WE CLAIM
1. A method of using fast MIPV6 to trigger faster L2 handover of a mobile node from an Initial Access Point associated with a Previous Access Router to a neighboring Access Point associated with a Next Access Router comprising the steps of:
At Previous Access Router:
(a1) sending neighboring Access Point id in the Handover Initiate message; (a2) getting neighboring Access Point's IPv6 Address from the Handover Acknowledge message;
(a3) transferring neighboring Access Point's and said mobile node's IPv6 Address to Initial Access Point; At Mobile Node:
(b1) sending neighboring Access Point id in the Fast Binding Update message; At Next Access Router:
(d) receiving neighboring Access Point id from the Handover Initiate message;
(c2) sending neighboring Access Point's IPv6 Address in the Handover Acknowledge message; At Initial Access Point:
(d1) getting neighboring Access Point's IPv6 address from Previous Access Router;
(d2) sending mobile node specific parameters directly to neighboring Access Point for prior allocation of resource at neighboring Access Point for mobile

node;
At the neighboring Access Point:
(e1) allocating prior resource for mobile node after receiving message from
initial Access Point.
2. A method as claimed in claim 1 wherein mobile node sends a Fast Binding Update message to Previous Access Router where neighboring Access Point ID is included in the Fast Binding Update.
3. A method as claimed in claim 1 wherein Previous Access Router sends Handover Initiate message with a Context Transfer and neighboring Access Point ID.
4. A method as claimed in claim 1 wherein Next Access Router sends Handover Acknowledge message with neighboring Access Point's IPv6 Address.
5. A method as claimed in claim 1 wherein Previous Access Router informs Initial Access Point regarding mobile node trying to move to neighboring Access Point and neighboring Access Point's IPv6 address is sent to Initial Access Point.
6. A method as claimed in claim 1 wherein Initial Access Point directly contacts neighboring Access Point through its IPv6 Address and sends Resource Allocation Parameters specific to mobile node.

7. A method of using fast MIPV6 to trigger faster L2 handover substantially described particularly with reference to the accompanying drawings.

Documents:

1979-CHE-2005 AMENDED CLAIMS 02-01-2013.pdf

1979-CHE-2005 AMENDED PAGES OF SPECIFICATION 02-01-2013.pdf

1979-CHE-2005 EXAMINATION REPORT REPLY RECEIVED 02-01-2013.pdf

1979-CHE-2005 FORM-1 02-01-2013.pdf

1979-CHE-2005 FORM-13 02-01-2013.pdf

1979-CHE-2005 FORM-3 02-01-2013.pdf

1979-CHE-2005 FORM-5 02-01-2013.pdf

1979-CHE-2005 OTHER PATENT DOCUMENT 02-01-2013.pdf

1979-CHE-2005 OTHER PATENT DOCUMENT 1 02-01-2013.pdf

1979-CHE-2005 POWER OF ATTORNEY 02-01-2013.pdf

1979-CHE-2005 FORM-13 19-06-2006.pdf

1979-che-2005-abstract.pdf

1979-che-2005-claims.pdf

1979-che-2005-correspondnece-others.pdf

1979-che-2005-description(complete).pdf

1979-che-2005-drawings.pdf

1979-che-2005-form 1.pdf

1979-che-2005-form 26.pdf


Patent Number 255955
Indian Patent Application Number 1979/CHE/2005
PG Journal Number 15/2013
Publication Date 12-Apr-2013
Grant Date 08-Apr-2013
Date of Filing 30-Dec-2005
Name of Patentee SAMSUNG INDIA SOFTWARE OPERATIONS PRIVATE LIMITED
Applicant Address BAGMANE LAKEVIEW,BLOCK B NO.66/1 BAGMANE TECH PARK,C.V.RAMAN NAGAR,BYRASANDRA BANGALORE 560 093
Inventors:
# Inventor's Name Inventor's Address
1 SAMEER KUMAR EMPLOYED AT SAMSUNG ELECTRONICS CO LTD INDIA SOFTWARE OPERATIONS (SISO) J.P TECHNO PARK 3/1 MILLERS ROAD BANGALORE 560 052 KARNATAKA
2 KISHORE MUNDRA EMPLOYED AT SAMSUNG ELECTRONICS CO LTD INDIA SOFTWARE OPERATIONS (SISO) J.P TECHNO PARK 3/1 MILLERS ROAD BANGALORE 560 052 KARNATAKA
3 LAKSHMI PRABHA GURUSAMY EMPLOYED AT SAMSUNG ELECTRONICS CO LTD INDIA SOFTWARE OPERATIONS (SISO) J.P TECHNO PARK 3/1 MILLERS ROAD BANGALORE 560 052 KARNATAKA
4 WABLE RANJISINH UDAYSINH EMPLOYED AT SAMSUNG ELECTRONICS CO LTD INDIA SOFTWARE OPERATIONS (SISO) J.P TECHNO PARK 3/1 MILLERS ROAD BANGALORE 560 052 KARNATAKA
PCT International Classification Number H04L 29/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA