InterDigital Inc (IDCC)

[mschere]

Lucent Chairs 802.21..and IDCC has the 802.21 handover Inventions..

IEEE 802.21


802.21
802.21 is an IEEE emerging standard. The standard is to provide seamless handover between networks of the same type as well as handover between different network types also called “Multi media Independent Handover” (MIH). The standard is to allow for handing over to and from cellular, GSM, GPRS, WiFi, Bluetooth and 802.11 networks.

The IEEE 802.21 working group started work in March 2004 and is chaired by Ajay Rajkumar from Lucent Technologies. More than 30 companies have joined the working group and the group plans to vote on a first draft of the protocol in May 2005.





Reasons for 802.21
Cellular networks and 802.11 networks employ handover mechanisms for handover within the same network and mobile IP employs handover mechanisms for handover across different networks of the same type. However, current 802 standards do not support handover between different types of networks. Moreover, existing 802 standards provide mechanisms for detecting and selecting network access points, but do not allow for detection and selection of network access points in a way that is independent of the of the network type.





Some of the Expectations
Allow roaming between 802.11 networks and 3g cellular networks.
Allow users to engage in ad hoc teleconferencing.
Apply to both wired and wireless networks.
Allow for use by multiple vendors and users.
Compatibility and conformance with other IEEE 802 standards.
Include definitions for managed objects that are compatible with management standards like SNMP.
Although security algorithms and security protocols will not be defined in the standard authentication, authorization, and network detection and selection will be supported by the protocol.




Implementation
Many vendors are building wireless products and participating in the development of the 802.21 standard. Current technologies such as 802.11 that accomplish handover use software to accomplish handovers and suggest that software will also be the way that handover will be implemented by 802.21. The use of software as a means to implement 802.21 should not cause large increases in the cost of networking devices.





Examples
A user should be able to unplug from an 802.3 network and get handed off to an 802.11 network.
A cellular phone user in the mist of a call should be able to enter an 802.11 network hotspot and be seamlessly handed off from a GPS network to the 802.11 network and back again when leaving the hotspot.




Similar technologies
Unlicensed Mobile Access (UMA) technology is basically a private version of 802.21. UMA is said to provide roaming and handover between cellular, GSM, GPRS, Bluetooth and 802.11 networks. However providers of the technology and standards do not guarantee interoperability. For more information on UMA you can go to http://www.umatechnology.org/.





External links
IEEE 802.21 web site (http://www.ieee802.org/21/)
Is Cellular Handoff Nigh? article (http://www.wi-fiplanet.com/columns/article.php/3310401)