doc.: IEEE j Submission Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Samsungs MAC Proposal for J] 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 Electronics 1 ] [Jung-hwan Hwang, Sung-weon Kang], Company [ETRI 2 ] Address [416, Maetan-3Dong, Yeongtong-Gu, Suwon-Si, Gyeonggi-Do, , Korea] Voice:[ ], FAX: [ ], (1){416, Maetan-3dong, Yeongtong-gu, Suwon-si, Gyeonggi-do, , South Korea}{ }{ (2){138 Gajeong-ro, Yuseong-gu, Deajeon, , South Korea} { }{ 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 j] Purpose:[For consideration by TG 4j group] Notice:This document has been prepared to assist the IEEE P 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 P July 2011 Slide 1,

doc.: IEEE j Submission July 2011, Slide 2 MAC Proposal for IEEE J Seung-Hoon Park, Jae-Seung Son, Kiran Bynam, Ranjeet K. Patro, Thenmozhi Arunan, Dr. Euntae Won Jung-hwan Hwang, Sung-weon Kang

doc.: IEEE j Submission 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 July 2011, Slide 3

doc.: IEEE j Submission Technical Requirements and scope PHY and MAC amendment for for support of medical devices in MBAN spectrum –Secondary usage of MBAN spectrum –Reusability of 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 July 2011, Slide 4

doc.: IEEE j Submission 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 July 2011, Slide 5

doc.: IEEE j Submission Easy Pairing Usage scenario –A medical expert wants to connect sensors to a patient, but monitoring device is far from the patient July 2011, Slide 6 Monitoring Device Patient Far from a patient Medical Expert

doc.: IEEE j Submission 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 July 2011, Slide 7 Monitoring Device Patient Far from a patient Medical Expert

doc.: IEEE j Submission 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 July 2011, Slide 8

doc.: IEEE j Submission Easy Pairing July 2011, Slide 9 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 Granting Association Authority Intermediating data for pairing Connection establishment j NFC, RFID, etc & Problem Solution

doc.: IEEE j Submission 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 July 2011, Slide 10

doc.: IEEE j Submission 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 July 2011, Slide 11 B MBP CAPBInactive Period Active Period

doc.: IEEE j Submission Mutual Broadcast Period (MBP) July 2011, Slide 12 BMBPCAP Device 1 Coordinator E- CAP Device 2 Device 3 Device 4 Q Q Q Q X X Q Q Q Q Q Q Q Q X X Device 5 Q Q E- CAP Q Q Q Q X N- CAP E- CAP Q Q N- CAP B-CAP Q Q X CAZ 1CAZ 2CAZ 3CAZ 4CAZ 5CAZ 6 MBZ 1 MBZ 2 MBZ 3 MBZ 4 MBZ 5 MBZ 6 *Q: QoS information broadcast (queue length, etc)*E-CAP (Exclusive CAP), N-CAP (Normal CAP), B-CAP (Background CAP)

doc.: IEEE j Submission 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 July 2011, Slide 13 MBZ 1MBZ 2 Mini backoff slot

doc.: IEEE j Submission 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 July 2011, Slide 14

doc.: IEEE j Submission 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 July 2011, Slide 15

doc.: IEEE j Submission 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 July 2011, Slide 16 [Reference] R. E. Mirollo and S. H. Strogatz, “Synchronization of pulse-coupled biological oscillators,” Journal on Applied Mathematics, vol. 50, pp. 1645–1662, Dec

doc.: IEEE j Submission Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN 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. July 2011, Slide 17 Fire A B C A B C D E D E C A B D E C * Pulse-Coupled Oscillator (PCO)

doc.: IEEE j Submission 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. July 2011, Slide 18 Fire A B C D E A B C D E A B C D E C

doc.: IEEE j Submission Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Unslotted CSMA-CA –Using PCO anti-phase synchronization July 2011, Slide 19 A’s CAP E’s CAP D’s CAP C’s CAP B’s CAP Anti-sync word A E D C B

doc.: IEEE j Submission 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 July 2011, Slide 20

doc.: IEEE j Submission Unslotted & Slotted CSMA-CA at Nonbeacon-enabled PAN Slotted CSMA-CA –Using both PCO in-phase & anti-phase synchronization July 2011, Slide 21 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 A B C D E

doc.: IEEE j Submission 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 July 2011, Slide 22

doc.: IEEE j Submission Congestion Avoidance at Relay Node July 2011, Slide 23 H H C C F F G G D D E E Data transmission B B A A Congestion arises at Node B

doc.: IEEE j Submission 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) July 2011, Slide 24

doc.: IEEE j Submission Congestion Avoidance at Relay Node July 2011, Slide 25 A A F F G G D D E E Congestion Avoidance Response Data transmission B B C C H H

doc.: IEEE j Submission Congestion Avoidance at Relay Node July 2011, Slide 26 C C A A F F G G D D E E Congestion Avoidance Response Data transmission H H B B

doc.: IEEE j Submission Coordinator Switching July 2011, Slide 27 Device (RFD) Device (RFD) Device (RFD) Device (RFD) Device (FFD) Device (FFD) Device (FFD) Device (FFD) Coordinator 1 Coordinator 2 Device (RFD) Device (RFD)

doc.: IEEE j Submission 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 July 2011, Slide 28

doc.: IEEE j Submission 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 July 2011, Slide 29

doc.: IEEE j Submission 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 July 2011, Slide 30 Mutual Broadcast Period Unslotted & Slotted CSMA-CA for Nonbeacon-enabled PAN Proxy Association procedure Service based Discovery Congestion Avoidance Coordinator Switching