Roaming Between GSM/UMTS and IMS Networks

Vikas Bajaj

3rd International ICST Conference on COMmunication System SoftWAre and MiddlewaRE

Research Article

Roaming Between GSM/UMTS and IMS Networks

Cite: BibTeX Plain Text

@INPROCEEDINGS{10.1109/COMSWA.2008.4554462,
    author={Vikas Bajaj},
    title={Roaming Between GSM/UMTS and IMS Networks},
    proceedings={3rd International ICST Conference on COMmunication System SoftWAre and MiddlewaRE},
    publisher={IEEE},
    proceedings_a={COMSWARE},
    year={2008},
    month={6},
    keywords={component; Roaming; IMS; VLR; S-CSCF},
    doi={10.1109/COMSWA.2008.4554462}
}

Vikas Bajaj
Year: 2008
Roaming Between GSM/UMTS and IMS Networks
COMSWARE
IEEE
DOI: 10.1109/COMSWA.2008.4554462

Vikas Bajaj¹^,*

1: System Engineering and Emerging Technologies Aricent Bangalore, India

*Contact email: Vikas.Bajaj@aricent.com

Abstract

Operators around the world are planning deployment of IMS Networks. It is therefore expected that GSM, UMTS and IMS Networks will co-exist for several years before full transition to IMS networks happens. There is a need therefore to support roaming of users from the legacy GSM/UMTS to IMS networks if the user device hosts IMS client software. This paper analyzes the problem and identifies the need for a VLR functional entity in the IMS network. It evaluates architectural alternatives for VLR placement and recommends use of one alternative. Finally, it captures the call flows for Registration, Call origination and Call termination to validate the recommended architectural alternative.

Keywords: component; Roaming; IMS; VLR; S-CSCF

Published: 2008-06-27
Publisher: IEEE
Modified: 2010-05-16

: http://dx.doi.org/10.1109/COMSWA.2008.4554462