<November 2011> 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. Matt Johnson, Itron

An enhancement to the 15.4e RIT Protocol <November 2011> RIT Enhancement An enhancement to the 15.4e RIT Protocol Matt Johnson, Itron

<November 2011> Background 15.4e MAC enhancements add valuable flexibility like RIT, but sensors aren’t always smart enough to know when to ask if there is data queued on the coordinator for them. And we want some predictability for downlink communications Also, adding RIT transmissions to query for possible queued data reduces battery life and adds network traffic in addition to regular traffic Matt Johnson, Itron

<November 2011> Implicit RIT Implicit RIT turns on the endpoint receiver once after each (asynchronous) transmission (not just after a RIT packet) to enable reception of data from the coordinator With professional installation, all endpoints are programmed with system-wide defaults at installation. 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, Itron

Receiver Initiated Transmission (RIT) <November 2011> Receiver Initiated Transmission (RIT) Matt Johnson, Itron

<November 2011> RIT Matt Johnson, Itron

One RX period per Transmission, delay and RX duration set system-wide <November 2011> I-RIT One RX period per Transmission, delay and RX duration set system-wide Matt Johnson, Itron