1. doc.: IEEE 802.15-11-0797-01-004k Submission Matt Johnson, ItronSlide 1 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Implicit RIT Enhancement to RIT] Date Submitted: [7 November 2011 ] Source: [Matt Johnson] Company [Itron] Address [2111 N Molter RD, Liberty Lake, WA 99019, USA] Voice:[+1 509-891-3364], FAX: [+1 509-891-3896], E-Mail:[matt.johnson@itron.com] Re: [ Enhancement of 15.4e RIT for 15.4k] Abstract:[This document describes an enhancement of 15.4e RIT for 15.4k to improve battery life and availability for downlink communications.] Purpose:[Proposal for consideration of inclusion into the baseline for the 802.15.4k standard.] Notice:This document has been prepared to assist the IEEE P802.15. 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 acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.

2. doc.: IEEE 802.15-11-0797-01-004k Submission RIT Enhancement An enhancement to the 15.4e RIT Protocol Matt Johnson, ItronSlide 2

3. doc.: IEEE 802.15-11-0797-01-004k Submission Background 15.4e MAC enhancements add valuable flexibility like RIT, but sensors arent always smart enough to know when to ask if there is data queued on the coordinator for them. We want some predictability for downlink communications Adding RIT transmissions to query for possible queued data reduces battery life and adds network traffic in addition to regular traffic Matt Johnson, ItronSlide 3

4. doc.: IEEE 802.15-11-0797-01-004k Submission Implicit RIT For non-beaconed networks, Implicit RIT turns on the endpoint receiver once after each transmission to enable reception of data from the coordinator With professional installation, all endpoints are programmed with system-wide defaults at installation and changed by upper level applications after deployment This approach: –Removes extra network traffic just to query the coordinator for waiting data –Provides predictable availability of endpoints for downlink traffic –All while supporting very long battery life in endpoints Matt Johnson, ItronSlide 4

5. doc.: IEEE 802.15-11-0797-01-004k Submission Receiver Initiated Transmission (RIT) Matt Johnson, ItronSlide 5

6. doc.: IEEE 802.15-11-0797-01-004k Submission RIT Matt Johnson, ItronSlide 6

7. doc.: IEEE 802.15-11-0797-01-004k Submission I-RIT Matt Johnson, ItronSlide 7 One RX period per Transmission, delay and RX duration set system-wide

8. doc.: IEEE 802.15-11-0797-01-004k Submission Summary I-RIT enhances existing 15.4e RIT mechanism Shifts burden of decision making to the coordinator which has greater resources and power Provides predictability for downlink communications Provides a mechanism to support very long (>20 year) battery life in endpoints Matt Johnson, ItronSlide 8