July 2011 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Samsungs MAC Proposal for 802.15.4J] Date Submitted: [5 July 2011] Source: [Seung-Hoon Park, Jae-Seung Son, Kiran Bynam, Ranjeet.K.Patro, Taehan Bae, Thenmozhi Arunan, Dr.Euntae Won], Company [Samsung Electronics1] [Jung-hwan Hwang, Sung-weon Kang], Company [ETRI2] Address [416, Maetan-3Dong, Yeongtong-Gu, Suwon-Si, Gyeonggi-Do, 443-742, Korea] Voice:[+82-10-9349-9845], FAX: [+82-31-279-2441], E-Mail:[shannon.park@samsung.com] {416, Maetan-3dong, Yeongtong-gu, Suwon-si, Gyeonggi-do, 443-742, South Korea}{+82-31-279-4960}{ etwon@samsung.com } {138 Gajeong-ro, Yuseong-gu, Deajeon, 305-700, South Korea} {+82-42-860-5625}{ jhhwang@etri.re.kr } Re: [Call for Proposals, March 2011] [If this is a response to a Call for Contributions, cite the name and date of the Call for Contributions to which this document responds, as well as the relevant item number in the Call for Contributions.] [Note: Contributions that are not responsive to this section of the template, and contributions which do not address the topic under which they are submitted, may be refused or consigned to the “General Contributions” area.] Abstract: [This document describes the Samsungs MAC Proposal to 802.15.4j] Purpose: [For consideration by TG 4j group] 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. <Seung-Hoon Park>, <Samsung Electronics>

July 2011 MAC Proposal for IEEE 802.15.4J Seung-Hoon Park, Jae-Seung Son, Kiran Bynam, Ranjeet K. Patro, Thenmozhi Arunan, Dr. Euntae Won Jung-hwan Hwang, Sung-weon Kang <Seung-Hoon Park>, <Samsung Electronics>

Outline Technical Requirements MAC Requirements Proposed ideas Summary July 2011 Outline Technical Requirements MAC Requirements Proposed ideas Easy Pairing Service based Discovery Mutual Broadcast Period Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Congestion Avoidance Coordinator Switching Summary <Seung-Hoon Park>, <Samsung Electronics>

Technical Requirements and scope July 2011 Technical Requirements and scope PHY and MAC amendment for 802.15.4 for support of medical devices in MBAN spectrum Secondary usage of MBAN spectrum Reusability of 802.15.4 protocol and PHY to enable the shifting of spectrum to 2.4 GHz ISM band in case of congestion in MBAN spectrum Spectrum usage limited to data transmission intended for diagnosis, treatment of patients <Seung-Hoon Park>, <Samsung Electronics>

MAC Requirements Low power consumption QoS for medical data Mobility July 2011 MAC Requirements Low power consumption Low duty cycling QoS for medical data Enhanced channel access scheme Robust mesh networking Mobility Seamless monitoring Support for easy pairing Intuitive/autonomous device discovery simple association procedure <Seung-Hoon Park>, <Samsung Electronics>

Easy Pairing Usage scenario July 2011 Easy Pairing Usage scenario A medical expert wants to connect sensors to a patient, but monitoring device is far from the patient Medical Expert Far from a patient Patient Monitoring Device <Seung-Hoon Park>, <Samsung Electronics>

Easy Pairing Usage scenario July 2011 Easy Pairing Usage scenario So the medical expert uses portable device to get patient record and connect sensors by touch-based communication (e.g. NFC) to the healthcare system of the patient Medical Expert Far from a patient Patient Monitoring Device <Seung-Hoon Park>, <Samsung Electronics>

Easy Pairing Required functions July 2011 Easy Pairing Required functions Portable device intermediates pairing procedure between coordinator and sensor devices Coordinator grants association authority to the portable device with required information Coordinator allows association request for sensors from the portable device <Seung-Hoon Park>, <Samsung Electronics>

Easy Pairing Problem Solution July 2011 Desirable Link Monitoring Device 1 Patient 1 Medical Expert Monitoring Device 2 Patient 2 Sensor Undesirable Link Desirable Link Monitoring Device 1 Patient 1 Medical Expert Monitoring Device 2 Patient 2 Sensor 1 2 3 Granting Association Authority Intermediating data for pairing Connection establishment 802.15.4j NFC, RFID, etc & <Seung-Hoon Park>, <Samsung Electronics>

Easy Pairing Coordinator Portable Device Sensor Device July 2011 Grant Association Proxy Authority Get Patient ID Pairing procedure Association Information Request Association Information Response *Association Proxy Request may have information such as Portable Device ID, Patient ID, Sensor Device Information List, etc Association Proxy Request* Association Proxy Response Association Response : 802.15.4j new command : NFC, RFID, etc : 802.15.4 reuse <Seung-Hoon Park>, <Samsung Electronics>

Service based Discovery July 2011 Service based Discovery Motivation There may be many different types of coordinators Sensor may consume much power to scan and connect all coordinators, and find the proper one according to service type Solution Service ID in Beacon frame <Seung-Hoon Park>, <Samsung Electronics>

Mutual Broadcast Period (MBP) July 2011 Mutual Broadcast Period (MBP) Objectives Enhanced channel access scheme Load balancing to avoid much back-offs To inform additional information such as queue length among devices Required functions Additional period using CSMA-CA for mutual broadcasting among devices B MBP CAP Inactive Period B Active Period <Seung-Hoon Park>, <Samsung Electronics>

Mutual Broadcast Period (MBP) July 2011 Mutual Broadcast Period (MBP) B MBP CAP Device 1 Coordinator E-CAP Device 2 Device 3 Device 4 Q X Device 5 N-CAP B-CAP CAZ 1 CAZ 2 CAZ 3 CAZ 4 CAZ 5 CAZ 6 MBZ 1 2 3 4 5 6 *Q: QoS information broadcast (queue length, etc) *E-CAP (Exclusive CAP), N-CAP (Normal CAP), B-CAP (Background CAP) <Seung-Hoon Park>, <Samsung Electronics>

Mutual Broadcast Period (MBP) July 2011 Mutual Broadcast Period (MBP) Operation Device broadcasts short QoS information (using CSMA-CA with shorter back-off slot length) during MBZ(Mutual Broadcast Zone) which is selected to notify the intention of access to corresponding CAZ(Contention Access Zone) Device can select one or multiple of MBZs/CAZs according to traffic demand MBZ 1 MBZ 2 Mini backoff slot <Seung-Hoon Park>, <Samsung Electronics>

Mutual Broadcast Period (MBP) July 2011 Mutual Broadcast Period (MBP) 3 different types of CAPs Exclusive CAP for device which broadcasts successfully at MBZ Normal CAP for device which just listens during corresponding MBZ when nobody broadcasts successfully same as original CAP Background CAP for device which failed at all trials over MBP Greedy level of CSMA-CA transmission Exclusive CAP > Normal CAP > background CAP <Seung-Hoon Park>, <Samsung Electronics>

Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN July 2011 Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Motivation Nonbeacon mode is useful for low power consumption and simplicity However, Nonbeacon mode has low performance due to asynchrony within devices Solution Synchronized channel access mechanism at Nonbeacon-enabled PAN <Seung-Hoon Park>, <Samsung Electronics>

Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN July 2011 Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Approach for synchronization Not MAC-level synchronization No timestamp No packet exchange within devices  a little error from delay PHY-level synchronization Using known symbols (e.g. sync symbols) Low power consumption & fast convergence E.g. Pulse-Coupled Oscillator synchronization [Reference] R. E. Mirollo and S. H. Strogatz, “Synchronization of pulse-coupled biological oscillators,” Journal on Applied Mathematics, vol. 50, pp. 1645–1662, Dec. 1990. <Seung-Hoon Park>, <Samsung Electronics>

Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN July 2011 Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN * Pulse-Coupled Oscillator (PCO) PCO In-phase Synchronization (a) Each oscillator has its own phase and firing frequency with same period T. (b) Oscillator B receives positive stimulus and promote firing frequency, oscillator E receives negative stimulus and repress the firing frequency. (c) After iterations, the phase between each oscillator becomes equal and in-phase synchronization is realized. Fire A B C D E <PCO In-phase Synchronization> <Seung-Hoon Park>, <Samsung Electronics>

Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN July 2011 Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN PCO Anti-phase Synchronization (a) Each oscillator has its own phase and firing frequency with same period T. (b) Oscillator B receives positive stimulus and promote firing frequency, oscillator E receives negative stimulus and repress the firing frequency. (c) After iterations, the phase offset between each oscillator becomes equal and anti-phase synchronization is realized. Fire A B C D E <PCO Anti-phase Synchronization> <Seung-Hoon Park>, <Samsung Electronics>

Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN July 2011 Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Unslotted CSMA-CA Using PCO anti-phase synchronization A’s CAP E’s CAP D’s CAP C’s CAP B’s CAP Anti-sync word A E B D C <Seung-Hoon Park>, <Samsung Electronics>

Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN July 2011 Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Unslotted CSMA-CA Each device calculates its own CAP duration based on neighbor devices’ firing time For example, device A detects the timing of its next firing during the previous period Device A decides its own CAP from A’s firing to next firing (E’s firing) E’s firing may be changed but only backwards So A’s CSMA-CA transmission will not affect E’s operation <Seung-Hoon Park>, <Samsung Electronics>

Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN July 2011 Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Slotted CSMA-CA Using both PCO in-phase & anti-phase synchronization A’s CAP E’s CAP D’s CAP C’s CAP B’s CAP Anti-sync Word A Sync Word E D C B <Seung-Hoon Park>, <Samsung Electronics>

Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN July 2011 Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Slotted CSMA-CA Each device calculates its own CAP duration based on neighbor devices’ firing time of Anti-sync Word (The method is same as unslotted CSMA-CA case) Each device refer the firing time of Sync-word of its own, as the back-off slot boundary All Sync-word and related oscillators’ phase are going into same phase, and finally converged <Seung-Hoon Park>, <Samsung Electronics>

Congestion Avoidance at Relay Node July 2011 Congestion Avoidance at Relay Node Data transmission H C F A B G Congestion arises at Node B D E <Seung-Hoon Park>, <Samsung Electronics>

Congestion Avoidance at Relay Node July 2011 Congestion Avoidance at Relay Node Problem a relay node receives data from a plurality of sensor nodes at the same time, congestion arises due to the bottleneck of buffer overflow Solution a relay node broadcasts a response signal comprising congestion-related information with respect to data transmitted to the relay node from a certain sensor node, and then adjacent sensor nodes learn the state of the certain sensor node by referring to the congestion-related information comprised in the response signal Congestion related information (4 levels) <Seung-Hoon Park>, <Samsung Electronics>

Congestion Avoidance at Relay Node July 2011 Congestion Avoidance at Relay Node Data transmission H Congestion Avoidance Response C F A B G D E <Seung-Hoon Park>, <Samsung Electronics>

Congestion Avoidance at Relay Node July 2011 Congestion Avoidance at Relay Node Data transmission H Congestion Avoidance Response C F A B G D E <Seung-Hoon Park>, <Samsung Electronics>

Coordinator Switching July 2011 Coordinator Switching Device (FFD) Device (RFD) Coordinator 1 Coordinator 2 Device (RFD) Device (RFD) Device (FFD) <Seung-Hoon Park>, <Samsung Electronics>

Coordinator Switching July 2011 Coordinator Switching Proactive approach Motivation The method which can promptly replace the present coordinator with another device if an unexpected situation happens so that the present coordinator cannot suddenly broadcast a sync signal Operation 1) selecting a coordinator that broadcasts a sync signal for synchronizing network 2) selecting devices and setting a priority of the selected replacement coordinators 3) transmitting the priority to the selected replacement coordinator 4) if the sync signal is not broadcast for a predetermined time, the replacement coordinator becomes a new coordinator in accordance with the set priority <Seung-Hoon Park>, <Samsung Electronics>

Coordinator Switching July 2011 Coordinator Switching Active approach Motivation The method that can broadcast information for changing coordinator operation, after checking channel degradation or PAN ID confliction Operation 1-1) when bad channel status is reported from device or checked by coordinator, or 1-2) when PAN ID conflict notification command is received from device 2) deciding coordinator operation changing 3) Change information (channel number, PAN ID, etc) is broadcasted in beacon frame with coordinator realignment command <Seung-Hoon Park>, <Samsung Electronics>

Summary Low power consumption QoS for medical data Mobility July 2011 Summary Low power consumption Low duty cycling QoS for medical data Enhanced channel access scheme Robust mesh networking Mobility Seamless monitoring Support for easy pairing Intuitive/autonomous device discovery simple association procedure Mutual Broadcast Period Unslotted & Slotted CSMA-CA for Nonbeacon-enabled PAN Congestion Avoidance Coordinator Switching Proxy Association procedure Service based Discovery <Seung-Hoon Park>, <Samsung Electronics>