Browse Prior Art Database

A method used for seamless WiMAX-3GPP handover

IP.com Disclosure Number: IPCOM000146992D
Original Publication Date: 2007-Mar-02
Included in the Prior Art Database: 2007-Mar-02
Document File: 4 page(s) / 197K

Publishing Venue

Motorola

Related People

Linlin Yang: AUTHOR [+2]

Abstract

A method used for seamless WiMAX-3GPP handover is described. This method helps a MS (mobile station) handover between WiMAX and 2G/3G networks seamlessly.

This text was extracted from a Microsoft Word document.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 45% of the total text.

A method used for seamless WiMAX-3GPP handover

Author: Linlin Yang; Jinghu Luo

Abstract

A method used for seamless WiMAX-3GPP handover is described. This method helps a MS (mobile station) handover between WiMAX and 2G/3G networks seamlessly.

WiMAX forum (NWG) has a comprehensive mechanism to ensure data integrity during handover procedure*1, while 3GPP network also has RNC-CN data forward message to ensure seamless handover within 3GPP network. WiMAX and 3GPP network have different data integrity mechanism during handover, so our method is useful to ensure data integrity to achieve seamless WiMAX-3G handover.

Our idea complies with 3GPP-WLAN interworking model (3GPP R6). The method includes below aspects:

1.         When MS makes handover from 3GPP network to WiMAX, data forwarding mechanism is specified: from serving RNC to target WiMAX ASN/BS via Core Network (CN).

2.         When MS moves from WiMAX to 3GPP, WiMAX network have two options for data integrity during handover:

a)         Change current WiMAX RAN level data forward mechanism, notify serving ASN/BS to forward buffering data to CN, then to target RNC.

b)        If 3GPP standard agrees to introduce a new interface between RNC/BSC(we names it Iur-w), data forward mechanism of WiMAX is more effective way to forward buffering data to target RNC(BSC) since CN can be ignored.

3.         Introduce new data forward strategy. So different strategy can be applied to different service type according to its characteristics. ¬†E.g., Transfer delay and jitter are more important for real time traffic; packet loss rate is more important for non real time traffic.

This disclosure is mainly used in implementing scenario 4/5 of 3G-WLAN inter-working*2.

Background

Current 3G or 2G/3G network has a data forward mechanism from RNC/BSC to CN during handover, when a handover occurs in different RNC/BSCs, all unsent/un-acked data buffered in serving RNCs will be sent to CN, then CN help sent them to new target RNCs/BSCs. When UE handover is executed, data in serving RNC buffer is sent back to CN to ensure data integrity. We can think Data forward is Core Network (CN) level.

WiMAX network uses another data forward solution. During a handover procedure, all unsent data will be forwarded directly from serving ASN/BS to target ASN/BS. When MS handover is executed, data in serving ASN/BS buffer is sent directly to target ASN/BS. We can think this type of Data forward is RAN level.

3GPP specified 3G-WLAN inter-working scenario (total 6 kinds) in Release 6/7(22.934, 23.234, 23.934) to allow interworking between 3G and wireless IP network (such as WLAN, WiMAX), But it does not specify the detailed procedure.

There are already some patent and paper to mention how to help do handover between 3G and Wireless IP network. The shortcoming of them is: all publications focus on control plane, which means handover signaling...