1. 1 IEEE 802.21 MEDIA INDEPENDENT HANDOVER DCN: 21-07-0055-00-0000-Multi-Radio-Paging Title: Multi-Radio Paging Study Group Request Date Submitted: March, 2007 Presented at IEEE 802.21 session #19 Orlando Authors or Source(s): Behcet Sarikaya, Phil Barber (Huawei) Muthu Venkatachalam, Vivek Gupta, Emily Qi (Intel Corporation) Benjamin Koh (Panasonic) Peretz Feder (Alcatel-Lucent) Abstract: This presentation describes a few single radio paging environment and then introduces the need for supporting multi- radio paging. The aim is to propose that a Study Group be established to assess whether there is justification to form a task group to define a standard IEEE 802.21 Media Independent Paging Service in a multi-radio environment

2. 2 IEEE 802.21 presentation release statements This document has been prepared to assist the IEEE 802.21 Working Group. 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. 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 802.21. The contributor is familiar with IEEE patent policy, as outlined in Section 6.3 of the IEEE-SA Standards Board Operations Manual and in Understanding Patent Issues During IEEE Standards Development http://standards.ieee.org/board/pat/guide.html> Section

3. 3 Agenda Motivation Existing single radio paging schemes Paging in multi-radio environment Proposed SG scope and work

4. 4 Motivation For a single radio MN, idle Mode and Paging have already been proposed independently in WiMax, 3GPP and WiFi to extend battery standby time In a multi radio environment, the MN may have multiple radios and each radio may be in connected or idle state. There is an opportunity to provide paging service via connected radio and aggregate paging messages across multiple radios –Fewer paging messages across network infrastructure –Fewer number of active radios on MN Multi Radio Paging can lead to considerable power saving at the MN and also provide radio/network/device resource optimization at the mobile communication infrastructure More on the savings in backup slides…

5. 5 Use Case of Idle Mode & Paging with a single Radio Data packets Paging Controller Idle Mode messages Enter Idle Mode Location Update Exit Idle Mode PagingPaging PagingPaging Data packets

6. 6 3GPP- LTE Paging 3GPP-LTE Network Architecture 3GPP-LTE Paging Protocols UE enters IDLE mode when there is no activity. Discontinuous Reception (DRX) – UE uses DRX in IDLE mode, i.e. wakes up periodically to check for paging messages. UE learns DRX cycle length upon network entry from the eNodeB. UE is registered at Tracking Area Level. Already exists in todays networks

7. 7 WiMAX Paging Paging controller (PC) is a logical entity that administers activity of Idle mode MS. It may be co-located with BS or ASN Gateway. A PC may monitor one or more paging groups. Paging Agent (PA) entity, co-located with BS, handles the interaction between PC and paging functionality implemented in BS. Location Register (LR) is a database that contains information about Idle mode MSs. PC is responsible for sending paging messages and handling location updates.

8. 8 WLAN Paging Currently no paging for WLANs but a proposal exists Idle Mode Operation –AP and Client advertises Paging Capability Discovery –Client enters Idle Mode if there is no incoming traffic –AP broadcasts Paging Indications (Paging ID), and client wakes up to receive paging indication –Client exits Idle Mode when client is paged Paging Group (PG) - a group of APs in which STA can be paged –Provides a collection of BSSs which a Client may traverse without requiring re- association –A Client must reassociate if it transitions to an AP in a different Paging Group Paging Server –Provides Paging Services and Serves one or more Paging Groups Paging group #1 Paging group #2 Paging Server #2 Paging group #3 Paging Server #1

9. 9 Paging Summary in a single radio environment For each individual radio: Key Paging Messages –Paging Capability Discovery –Enter/Exit Idle Mode –Location Update (sent by MN aka Idle Mode Update) MS sends location update to the infrastructure –Paging Indication (sent by infrastructure) MS periodically wakes up to check whether it is being paged or not Key Concept and Logical Entity –Paging Group or Paging Area –Paging Server or Paging Controller

10. 10 Multi-Radio Paging Potential Benefits In a multi-radio environment, the MN may have multiple radios and each radio may be in connected or idle states Potential Multi Radio Paging Benefits –All Paging messages via the connected radio Paging Indication Message sent via the connected radio Location Update via the connected radio –Paging aggregation minimizes message exchange Paging Indication Message aggregation Location Update aggregation Idle Mode Enter/Exit aggregation Therefore, unified multi-radio paging primitives are needed for multi-radio environments

11. 11 Multi-Radio Paging Potential Benefits Tight-coupling solutions for 802.16 & 802.11 planned in future releases Multi-radio MN can enjoy benefits of location update on connected radio (WLAN), 802.16&802.11 idle mode entry using 802.11 radio, 802.16&802.11 paging on 802.11 radio CSN HA HAAA ASN GW * Access Point ASN WLAN ASN GW Multi-Radio NIC BS CSN

12. 12 Multi-Radio Paging Potential Challenges There are potentially several security issues to consider especially when networks cross operator administrative domains There are issues around evolution of paging systems, does MRP, i.e. inter-operability restrict innovation in 3GPP LTE? Given that paging systems are evolving and new paging systems are very efficient, are the gains from MRP likely to be significant or very modest? Are there potentially issues on why MRP needs to function in L2? More details are in backup slides

13. 13 Objective It is proposed that a Study Group be established to assess whether there is justification to form a task group to define a standard IEEE 802.21 Media Independent Paging Service in multi-radio environment

14. 14 Proposed SG Scope Identify and quantify multi-radio paging benefits Identify technical scope Determine impacts on IEEE 802.16, 802.11, and other standards, for example: –Potential Remediation : Determine whether available mechanisms are economically feasible and of utility to the community –Threat Analysis: Identify security threats especially when networks cross operator administrative domains –MAC and IP layer message requirements: Identify the engagement with IEEE 802.16, 802.11, 802.15, 802.22, WiMAX, 3GPP LTE and 3GPP2 –IP layer message requirements: Identify the engagement with IETF Decide whether a TG is needed, and if so define PAR and 5Criteria.

15. 15 Reference 21-06-0701-00-0000-Media independent idle mode and paging.ppt, by Muthaih Venkatachalam (Intel Corporation) 11-07-0061-00-000v-presentation-paging-and-idle- mode.ppt, by Emily Qi et al 11-07-0058-01-000v-paging-power-saving-analysis- update.ppt, by Emily Qi et al

16. 16 Backup

17. 17 Paging via connected radio MSG #1, #2, #3, #4, and #5: IETF BS/AP Paging Announcement Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface MS receiving Paging Announcement Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface Scenario –User is browsing on the WiFi interface –User gets a voip call on the WiMAX interface. –WiMAX network needs to page the user

18. 18 Location Update via connected radio User has WiFi connection that is currently active and WiMAX connection that is idle. Instead of contending on the WiMAX airlink, MS uses the WiFi radio to perform location update for its WiMAX radio All MSGs: IETF BS/AP Location Update Request/Response Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface, Location Information MS Location Update Request/Response Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface, Location Information

19. 19 Aggregated Location Update If the PGs are overlapping, perform a single LU operation for multiple radios. Minimizes messaging and processing at the MS BS/AP Location Update Request/Response Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface, Location Information MS Location Update Request/Response Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface, Location Information MSGs: IETF Extended Location Update Message for Multi radio: IEEE 802.16, 802.11

20. 20 Paging-aggregation Page on a single idle radio to wake up multiple idle radios. Extended Paging Announcement Message for Multi radio: IEEE 802.16, 802.11 MS receiving Paging Announcement Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface BS/AP Paging Announcement Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface

21. 21 Idle mode Entry/Exit Scenario: Multiple radios are switched to idle mode –For example: when the user takes a break, his WiMAX, WiFi and 3G connections may go into idle mode IM Entry/Exit for radios i, j, k happens on radio-i. MSGs: IETF MS Enter/Exit Idle Mode Request/Response Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface, Location Information BS/AP Enter/Exit Idle Mode Request/Response Primitives: IEEE 802.21 Possible Contents: Paging and Paging Media/Radio Interface, Location Information Extended Idle Mode Request/Response messages for Multi radio: IEEE 802.16, 802.11

22. 22 Proposed Standard Engagements IEEE 802.21: Standard Message Primitives –Paging capability Primitives –Location Update Primitives –Enter/Exit Idle Mode (Radio State update) Primitives –Paging Indication Primitives IEEE 802.16, 802.11, LTE (?): MAC layer messages –RAN specific Containers/Transport to carry above messages 3GPP/WiMAX/IEEE: IP Layer messages (back end) –Messages between Paging Controllers –Between Paging Controller and PoA (BS/AP).

23. 23 Proposed Standard Engagements IETF: –MIPSHOP WG currently defining transport protocol for 802.21 –MRP needs MIPSHOP WG liaison for any IP transport issues –MONAMI6 WG on multiple wireless interface host mobility –MRP may propose MONAMI6 WG liaison for any IP Paging issues

24. 24 Comments/ Concerns There are potentially several security issues to consider especially when networks cross operator administrative domains –IPSec and IKEv2 available and widely used

25. 25 Comments/ Concerns (contd) There are issues around evolution of paging systems, does MRP, i.e. inter-operability restrict innovation in 3GPP LTE? –MPR is not about individual paging systems, so paging systems can evolve independent of MPR –The glues (IP layer backend messages) may need to be redefined

26. 26 Comments/ Concerns (contd) Given that paging systems are evolving and new paging systems are very efficient, are the gains from MRP likely to be significant or very modest? Multi-radio Paging gains are significant: –Due to resource allocation/ QoS, single-radio idle mode entry requires at least 4 message exchange with two messages over the air; the same for idle mode exit –For a 3 radio MN, Location update separately on single-radio requires a total of 3 * (4 + 4 + 4), 36 messages with 18 over the air –Aggregated LU procedure of multi-radio paging using the connected radio requires only 8 messages with 2 over the air

27. 27 Comments/ Concerns (contd) Given that paging systems are evolving and new paging systems are very efficient, are the gains from MRP likely to be significant or very modest? Multi-radio Paging gains are significant: –Single-radio paging potentially involves many (n) BSs in the same paging area broadcasting paging request messages. Only one BS reports success to the paging controller (PC), PC stops n-1 BSs –Paging via connected radio procedure of multi-radio paging avoids the search and requires only two messages

28. 28 Comments/ Concerns (contd) There are potentially issues on why MRP needs to function in L2? –The reasons are the same as for 802.21

29. 29 Motion Move that the IEEE 802.21 WG form a study group to determine how to formally describe the IEEE 802.21 Multi-Radio Paging functions and behaviors, with the intent to create a PAR and five criteria documents to form a new Task Group.