Idle Mode Operation for IEEE 802.11v March 2006 Idle Mode Operation for IEEE 802.11v Date: 2006-03-06 Authors: Sunggeun Jin, Sunghyun Choi, Youngsoo Kim, Kyunghun Jang Notice: This document has been prepared to assist IEEE 802.11. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.11. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures <http:// ieee802.org/guides/bylaws/sb-bylaws.pdf>, including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair <stuart.kerry@philips.com> as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE 802.11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at <patcom@ieee.org>. S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

March 2006 Abstract In this presentation a new operation mode called Idle Mode (IM) is proposed for the power saving requirement in TGv. The original proposal (IEEE 802.11-05/1263r2) was presented in January meeting. S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

Outline Brief Introduction to Idle Mode Operation March 2006 Outline Brief Introduction to Idle Mode Operation Idle Mode Operation within Mobility Domain Summary S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

Brief Introduction to Idle Mode Operation March 2006 Brief Introduction to Idle Mode Operation A new mode for “deep” sleep Major component Paging Concepts and terms AP reselection in order to receive beacons conveying paging information, new APs should be selected while a STA moves around Home-AP An AP which a mobile host signals to in order to enter the idle mode S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

Benefits Provided by Idle Mode (IM) March 2006 Benefits Provided by Idle Mode (IM) Benefits provided to STA Reduce the number of handoff operations Reduce the operational load required for handoff Save the power consumption required for handoff operation Filter the unnecessary broadcast and multicast frames save the power required for receiving broadcast and multicast frames Benefits provided to network Reduce the load required for handoff Save the resources to maintain connectivity with associated STAs S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

Idle Mode Operation Procedure March 2006 Idle Mode Operation Procedure S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

Idle Mode Operation within Mobility Domain March 2006 Idle Mode Operation within Mobility Domain Mobility Domain proposed in 11r A set of BSSs within the same ESS, identified by a Mobility Domain IEEE 802.11r Fast BSS transition is possible within Mobility Domain Within the same Mobility Domain, a common key hierarchy is accessible at all BSSs Access to common network service is available through all BSSs Idle Mode (IM) operation within Mobility Domain Mobility Domain can be used as Paging Area (PA) In the same Mobility Domain ( i.e., PA), a STA in IM can be paged Security related schemes proposed in IEEE 802.11r can be adopted as they are S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

IM Operation of a STA within Mobility Domain March 2006 IM Operation of a STA within Mobility Domain IM within Mobility Domain There are three major steps for IM procedure IM entrance, AP reselection, Paging IM entrance The beginning of IM operation initiated by a STA A STA transmits “Idle Mode Request” to Home-AP. “Idle Mode Request” is a newly defined management action frame All BSSs as well as Home-AP in the same Mobility Domain share PMK inherited by MSK or PSK to generate PTK. PMK is created when a STA is associated with a BSS within a Mobility Domain. It can be still available when the STA enters IM. Home-AP keeps the information for a STA in IM till the STA will be paged as if the STA is associated with the Home-AP. S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

IM Operation of a STA within Mobility Domain (cont.) March 2006 IM Operation of a STA within Mobility Domain (cont.) AP reselection The role of AP-reselection During AP-reselection, a STA in IM receives and checks Paging Indication Message (PIM) conveyed in beacon periodically. A STA does not need to receive every beacon. There is no Fast transition between BSSs even when a STA moves to other BSSs from Home-AP due to AP-reselection. PIM Management The indication bit of the PIM is generated by a hash function using a MAC address of a paged STA. Paging The role of paging The operation to page a STA in IM when a new frame destined to the STA is arrived. The paging procedure A STA re-associates with an AP immediately after receiving the PIM which indicates the STA is paged. Fast BSS transition from Home-AP to the newly associated AP is performed using Over-the-Air method defined in IEEE 802.11r. S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

Paging ID (PID) and Paging Indication Message (PIM) March 2006 Paging ID (PID) and Paging Indication Message (PIM) Paging ID (PID) The identification number to wake up a STA in IM for paging. two-octet. AP generates a PID upon the reception of ‘Idle Mode request’ frame. AP transmits ‘Idle Mode response’ frame with a PID to a STA. PID is not unique value across STAs within a given PA. Hash function generates a PID using MAC address. Multiple STAs can be assigned the same PID because of the characteristic. PIM PIM contained in beacon frame is transmitted periodically. Each bit in the PIM indicates which PID is activated for paging. A part of PID can be used to determine the bit offset in PIM. S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

Paging ID (PID) and Paging Indication Message (PIM) (cont.) March 2006 Paging ID (PID) and Paging Indication Message (PIM) (cont.) Bit generation in PIM A bit corresponding to lower bits of a PID is assigned and set when paging a STA. Considerations Multiple STAs could be paged because of the characteristic of hash function. Home-AP requests all APs in the Mobility Domain to page a STA with a particular MAC address. Even though multiple STA could try to re-associate with an AP, other STAs except the valid STA will fail to re-associate with the AP. The AP, which initiates paging, has the MAC address of the paged STA. Error codes to notify the failure reasons are defined. S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)

March 2006 Summary The proposed Idle Mode can reduce the number of handoff operations, which can save the power consumption required for handoff operation. The proposed scheme can interoperable with emerging standard like TGv Idle Mode operation outperforms PSM and can extend the standby time of a Mobile Host S. Jin, S. Choi (Seoul National U.), Y. Kim, K. Jang (Samsung)