This paper proposes a SIP-based session mobility management framework for achieving session handoff that is transparent to the underlying wireless or wired technology between network domains. Session mobility is concerned with a presentation session changing its attachment device from one client device to the other client device and still continuing the presentation session. This concept requires migrating related information of the current service execution, including service content, service data, etc, from one device to another device. Since different devices and their attached networks have different capabilities and performance, media streaming service quality should be adapted when the session handoff occurs. MPEG-21 efforts for multimedia adaptation to bring suitable multimedia services to users. MPEG-21 Digital Item Adaptation provides normative XML descriptions for handling multimedia content adaptation, but does not specify relations to existing technologies for transport mechanisms. Thus, we adopt the MPEG-21 DIA for multimedia session and usage environment description in our proposed SIP-based session mobility management framework.