<month year> doc.: IEEE 802.15-14-0286-00-0010 May 2014 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [L2 Preliminary Proposal] Date Submitted: [ 12 May, 2014] Source1: [Noriyuki Sato, Kiyoshi Fukui] Company [OKI] Address [2-5-7 Hommachi chuo-ku, Osaka, Japan] Voice:[+81-6-6260-0700], FAX: [+81-6-6260-0770], E-Mail:[sato652@oki.com, fukui535@oki.com] Re: [This is the original document.] Abstract: [This documents describes OKI’s L2R proposal to CfPP.] Purpose: [To make a proposal] 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. N. Sato and K. Fukui (OKI) <author>, <company>

L2R Preliminary Proposal <month year> doc.: IEEE 802.15-14-0286-00-0010 May 2014 L2R Preliminary Proposal TG10 presentation 11th May 2014 Waikoloa HA Noriyuki Sato / Kiyoshi Fukui OKI Electric Industry Co., Ltd. N. Sato and K. Fukui (OKI) <author>, <company>

<month year> doc.: IEEE 802.15-14-0286-00-0010 May 2014 Outline of L2R protocol Routing establishment consists of upward / downward route establishments Upward routing is established by exchanging information between neighbors. (many-to-one) Downward routing is established by sending information of parent-child relationship to the concentrator. (source routing) Both information are updated periodically. HOP-by-HOP retry L2R layer provides hop-by-hop retransmission Change route to an alternate parent BS switch consideration N. Sato and K. Fukui (OKI) <author>, <company>

Upward routing establishment <month year> doc.: IEEE 802.15-14-0286-00-0010 May 2014 Upward routing establishment All nodes broadcast “HELLO” frame to the neighbor nodes periodically. “HELLO” frame carries link costs between its neighbor nodes and itself. In the other words, outgoing link cost is told from the other side. (a) Each node decides incoming link cost. (b) A node decide the mutual link costs from the outgoing (a) and the incoming (b). HELLO frame also carries path cost. The Originator (concentrator, PAN coordinator or L2R former)’s cost is zero. A node receives path costs from its neighbors and its own path cost is calculated by using the derived mutual link cost. A node chooses the lowest one from them and broadcast to the neighbor nodes. N. Sato and K. Fukui (OKI) <author>, <company>

How to set a incoming link cost. May 2014 Node B has no neighbor information. Just after receiving a first hello from node A and C, node B sets a highest value as incoming link costs from these nodes. After receiving enough hellos, incoming link costs are updated to appropriate values. Node A Node B Node C NOA ① NOA AD LC 2 A 15 C ② NOA AD LC 2 A 1 C ③ NOA: Number of Address AD: Address LC: Link Cost N. Sato and K. Fukui (OKI)

Calculation of path cost & parent selection May 2014 Calculation of path cost & parent selection A node calculates path costs between each neighbor node. It selects the node which has the lowest path cost as the parent node. a LC = 2 1 Node h’s candidate parents 5 b f Neighbor ADDR PC LC My PC d 6 2 8 g 5 1 j 4 1 1 2 3 e 4 i c 2 4 2 2 g 3 PC: Path Cost LC: Link Cost 2 j d 1 2 1 h N. Sato and K. Fukui (OKI)

Downward routing establishment <month year> doc.: IEEE 802.15-14-0286-00-0010 May 2014 Downward routing establishment A node start to send RREC (route record) frame to its parent node periodically after upward routing is established. RREC carries the parent-child relationship information. Merged RREC is sent if RREC from a child is received. PAN coordinator gathers all parent-child relationship from the network. For the downward transmission, PAN coordinator send a frame by source routing. N. Sato and K. Fukui (OKI) <author>, <company>

Establishment of downward route May 2014 Establishment of downward route PAN coordinator (node A) achieve path to h by following steps. Node h send RREC to the PAN coordinator (node a). Each node on the path adds its address to address list of RREC. PAN coordinator gets path information to node h. Address list of RREC a NOA AD1 AD2 AD3 AD4 4 h j i f LC = 2 1 f ⇒ a 5 b f 1 NOA AD1 AD2 AD3 3 h j i 1 2 3 i ⇒ f e 4 i c 2 NOA AD1 AD2 2 h j 4 j ⇒ i 2 2 3 g 2 j d NOA AD1 1 h 1 h ⇒ j NOA: Number of Address AD: Address 2 1 h N. Sato and K. Fukui (OKI)

Hop-by-hop retry Hop-by-hop retransmission Change routing <month year> doc.: IEEE 802.15-14-0286-00-0010 May 2014 Hop-by-hop retry Hop-by-hop retransmission Retransmission timing is determined by macMinBE and macMaxBE is up to 2^(macMaxBE) * aUnitBackoffPeriod, which is intend to avoid neighbor collision L2R provides retransmission so that it retries after longer period than MAC provides. Change routing If transmission is failed to the parent, a node may change next hop to transmit. Next hop is chosen from candidates of parent which were obtained during upward route establishment / update N. Sato and K. Fukui (OKI) <author>, <company>

BS switch consideration <month year> doc.: IEEE 802.15-14-0286-00-0010 May 2014 BS switch consideration GW works as PAN coordinator Each BSs are connected to GW on the wires. A BS is downward next hop of GW. Even if one of BS is down, a node automatically updates routing information so that it connect to another BS. Hello GW BS1 BS2 BS3 BS4 Example of self healing functionality N. Sato and K. Fukui (OKI) <author>, <company>

Simulation result of 11x11 Number of nodes Distance from concentrator May 2014 Simulation result of 11x11 Number of nodes 11x11 = 121 Distance from concentrator 28 nodes on 1 hop distance. 72 on 2hops distance 20 on 3 hops distance Average 1.93hops N. Sato and K. Fukui (OKI)

Simulation result of 33x33 Number of nodes Distance 33×33=1089 May 2014 Simulation result of 33x33 Number of nodes 33×33=1089 Distance 28 nodes on 1 hop 76 nodes on 2 hops distance 124 nodes on 3hops distance 172 nodes on 4 hops dist. 220 nodes on 5 hops dist. 244 nodes on 6 hops dist. 160 nodes on 7 hops dist. 64 nodes on 8 hops dist. Average distance 4.99hops N. Sato and K. Fukui (OKI)

Condition of simulation May 2014 Condition of simulation Nodes within 3 units on the grid are neighbor where one unit is minimum distance between nodes on the grid. HELLO period: 64 (s) RREC: None L2R retransmission: Yes Delay of forwarding: 10 (ms) Data Size: 127 (Bytes) Sending period is set so that concentrator receive it 1 times per second. 11×11 each node sends once in 120 (sec) , 33×33once in 1088 (sec) NW establishment time All nodes detect route to the concentrator (s) – concentrator issued first hello (s) It may not always be optimum route. Data are sent after 15 minutes of begin of simulation . Number of trials 1 set consits (NW formation + data transmission 5 times) 100 sets of trials N. Sato and K. Fukui (OKI)

Result of simulation 11×11 33×33 Establishment time (s) 62.35 104.51 May 2014 Result of simulation 11×11 33×33 Establishment time (s) 62.35 104.51 Data arrival ration 0.999983 0.9999944 Average delay of data (s) 0.0446 0.1121 N. Sato and K. Fukui (OKI)