Internet Communications Using SIP : Delivering VoIP and Multimedia Services With Session Initiation Protocol {2Nd Ed.}

IEEE 802.21 Media-Independent Handover (MIH)

We will use in the this section the term “media” to refer to the Layer 2 of the IP
protocol stack, such as the various IEEE 802 wired and wireless standards,
wireless 3G networks, and others.
A multimodal mobile device can switch from one “media” (Layer 2 net-
work) to another and for real-time communications, as well as for streaming
multimedia. The IEEE 802.21 [18] is one of the standards organizations work-
ing to define the issues as they relate to the various L2 link layers. The other
standards body working at the IP network layer (Layer 3) and the application
layer (Layer 5) is the IETF. The IEEE and the IETF are consistently trying to
accommodate various commercial interests, such as the 3GPP and 3GPP2
organizations for 3G wireless networks.
The reference model for the IEEE 802.21 media-independent handover
(MIH) is shown in Figure 15.9, reflecting the standard proposal as of summer
2005 and it may take several years for the work standards to be completed.

Figure 15.9 The IEEE 802.21 architecture for media-independent handover

SIP

MIH Events

Link Events

MIH Commands

Link Commands

Information Service

MIH Function

Information Service

MIPv4 MIPv6

Upper layers (L3 and above) – IETF protocols

HIP ...other...

802.3 802.11

IEEE protocols

Lower layers (L2 and below)

802.16 3GPP 3GPP2

3G protocols

(WDCDMA) (CDMA2000)

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