doc.: IEEE //0128r0 Submission Slide 1 March 2006 J. Zheng, Samsung CUNY Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Wireless Mesh Personal Area Networks] Date Submitted: [5 March, 2006] Source: [Jianliang Zheng] Company [Samsung Lab at The City University of New York] Address [138th Street at Convent Avenue, New York, NY 10031, USA] Voice:[ ], FAX: [ ], Re: [IEEE ] Abstract:[This proposal presents an updated version of Samsung’s proposal for IEEE WPAN Mesh, including simulation results.] Purpose:[This proposal is provided to be adopted as a recommended practice for IEEE WPAN Mesh.] 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

doc.: IEEE //0128r0 Submission Slide 2 March 2006 J. Zheng, Samsung CUNY Wireless Mesh Personal Area Networks Zheng Jianliang Samsung CUNY

doc.: IEEE /0128r0 Submission Slide 3 March 2006 J. Zheng, Samsung CUNY Outline  Objectives  Adaptive Block Addressing (ABA) –ABA scheme –Simulations  ABA-based Mesh Routings –Adaptive Robust Tree (ART) Three phases Data forwarding Tree repair Meshed ART (MART) –Topology-guided Distributed Link State (TDLS) DLS scheme –Simulations  Highlights

doc.: IEEE /0128r0 Submission Slide 4 March 2006 J. Zheng, Samsung CUNY Objectives  To construct mesh networking layer over IEEE MAC and PHY, which features: –simple –self-configuring –adaptive –scalable –resource-efficient –robust

doc.: IEEE /0128r0 Submission Slide 5 March 2006 J. Zheng, Samsung CUNY Adaptive Block Addressing (ABA)

doc.: IEEE /0128r0 Submission Slide 6 March 2006 J. Zheng, Samsung CUNY ABA Scheme  Stage 1: Association  Stage 2: Children number collection  Stage 3: Address assignment –An adaptive tree (AT) is formed. –Additional addresses are reserved. A BJ ED C I HK LOG [0] FMN [1] [children#][children#]=[8][6] [5] [5][2] [1][2][1] [1] [3][1] [1][1] resv’ed: [beg,end]=[0,9000] branch1: [beg,end]=[9001,41000] branch2: [beg,end]=[41001,65000] [9001,13000] [13001,33000] [33001,41000] [41001,45000] [45001,65000] [13001,17000] [17001,21000] [21001,29000] [29001,33000] [33001,37000] [37001,41000] [45001,49000] [49001,61000] [61001,65000] [21001,25000] [25001,29000] [49001,53000] [53001,57000] [57001,61000] [17001,21000] [25001,29000] [53001,57000] [57001,61000] [61001,65000] [37001,41000] [29001,33000]

doc.: IEEE /0128r0 Submission Slide 7 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (1) Simulations  Experimental setup  Results  nodes (7 x 7)  nodes (16 x 16)  nodes (32 x 32)  nodes (64 x 16)

doc.: IEEE /0128r0 Submission Slide 8 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (2)  Simulation platform: NS + LR-WPAN LR-WPAN source code is available at  # of nodes: a x b (variable)  Area: (10 x a) x (10 x b) m2  Neighbor distance: 10 m  Tx range: 12 m  PAN Coordinator (PC): central node (or any designated node)  Network startup: –PC starts at: 0.0 –Any other node starts at: random time between 1.0 and 5.0 Experimental setup

doc.: IEEE /0128r0 Submission Slide 9 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (3) PAN Coordinator Node having associated but not yet collected children number Node having associated and collected children number 25 [18] Parent ID Node ID 49 nodes (7 x 7): Association and children number collection

doc.: IEEE /0128r0 Submission Slide 10 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (4) Latency Association: ~ 16.0 sec Children number collection: ~ 5.0 sec Address assignment: ~ 0.1 sec PAN Coord. Coordinator Device (leaf node) 49 nodes (7 x 7): Address assignment

doc.: IEEE /0128r0 Submission Slide 11 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (5) PAN Coordinator Node having associated but not yet collected children number Node having associated and collected children number 24 [40] Parent ID Node ID 256 nodes (16 x 16): Association and children number collection

doc.: IEEE /0128r0 Submission Slide 12 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (6) Latency Association: ~ 35.0 sec Children number collection: ~ 5.0 sec Address assignment: ~ 0.2 sec PAN Coordinator Coordinator Device (leaf node) 256 nodes (16 x 16): Address assignment

doc.: IEEE /0128r0 Submission Slide 13 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (7) PAN Coordinator Node having associated but not yet collected children number Node having associated and collected children number 80 [112] Parent ID Node ID 1024 nodes (32 x 32): Association and children number collection

doc.: IEEE /0128r0 Submission Slide 14 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (8) Latency Association: ~ 63.0 sec Children number collection: ~ 5.1 sec Address assignment: ~ 0.3 sec PAN Coordinator Coordinator Device (leaf node) 1024 nodes (32 x 32): Address assignment

doc.: IEEE /0128r0 Submission Slide 15 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (9) PAN Coordinator Node having associated but not yet collected children number Node having associated and collected children number 68 [4] Parent ID Node ID 1024 nodes (64 x 16): Association and children number collection

doc.: IEEE /0128r0 Submission Slide 16 March 2006 J. Zheng, Samsung CUNY ABA: Simulations (10) Latency Association: ~ sec Children number collection: ~ 5.4 sec Address assignment: ~ 0.7 sec PAN Coordinator Coordinator Device (leaf node) 1024 nodes (64 x 16): Address assignment

doc.: IEEE /0128r0 Submission Slide 17 March 2006 J. Zheng, Samsung CUNY ABA-based Mesh Routings Adaptive Robust Tree (ART) Topology-based Distributed Link State (TDLS)

doc.: IEEE /0128r0 Submission Slide 18 March 2006 J. Zheng, Samsung CUNY ART: Three Phases Initialization Phase (ABA) Operation Phase (Data Fwding) Recovery Phase (Tree Repair)

doc.: IEEE /0128r0 Submission Slide 19 March 2006 J. Zheng, Samsung CUNY ART: Data Forwarding  Normal data transmissions A0A0 B 9001 J ED C I H K L OG FMN [8][6] [5] [3][1] [0,9000] [9001,41000] [45001,65000] [49001,61000]  Nodes are still allowed to join the network [41001,65000] [61001,65000] –Example: Node C  node L (i.e.,  49001) [5][2] [9001,13000] [13001,33000] [33001,41000] [41001,45000 [1][2][1] [13001,17000] [17001,21000] [21001,29000] [29001,33000] [45001,49000] [1][1] [49001,53000] [53001,57000] [57001,61000]

doc.: IEEE /0128r0 Submission Slide 20 March 2006 J. Zheng, Samsung CUNY ART: Tree Repair (1) Approach 1 –a whole branch can be moved from one place to another –no address change A BJ ED C I HK LOG FMN First-level tree repair

doc.: IEEE /0128r0 Submission Slide 21 March 2006 J. Zheng, Samsung CUNY ART: Tree Repair (2) Approach 1 (cont.) A BJ ED C I HK LOG FMN Multi-level tree repair

doc.: IEEE /0128r0 Submission Slide 22 March 2006 J. Zheng, Samsung CUNY ART: Tree Repair (3) Approach 2 A BJ ED C I HK LOG FMN MART route RREP RREQ RCFM  Node K fails  Node J broadcasts an RREQ to locate node K, with a limited TTL.  All nodes below node K that have received the RREQ reply.  Node J selects the best path and sends a route confirmation (RCFM) message to activate it.

doc.: IEEE /0128r0 Submission Slide 23 March 2006 J. Zheng, Samsung CUNY ART: Tree Repair (4) Approach 2 (cont.) Data forwarding after repair A B J ED C I H K L OG FMN [1][1] [desIn,49001,61000,normal,33001] [desIn,49001,61000,normal,49001] parent=33001 [srcIn,49001,61000,normal,41001] [desIn,45001,65000,down,45001] [49001,53000] [53001,57000] [57001,61000] [3][1][45001,49000] [49001,61000] [61001,65000]

doc.: IEEE /0128r0 Submission Slide 24 March 2006 J. Zheng, Samsung CUNY Meshed ART (MART) A ED C I K LOG FMN [5][5][2] [9001,13000] [13001,33000] [33001,41000] [41001,45000] [45001,65000] [1] [8][6] [33001,37000] [37001,41000] [0,9000] [9001,41000] [41001,65000] [41001,65000] [9001,41000] [41001,65000] [33001,41000] …… B H J  Neighbors treat each other as a child. –Provide shorter path. –Reduce SPOFs.

doc.: IEEE /0128r0 Submission Slide 25 March 2006 J. Zheng, Samsung CUNY Topology-based Distributed Link State (TDLS) + Topology Learning (ABA) Distributed Link State TDLS

doc.: IEEE /0128r0 Submission Slide 26 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (1) The basic link state scheme A BJ ED C I H K LOG FMN 3-hop Link State (view of node J)

doc.: IEEE /0128r0 Submission Slide 27 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (2) The extended link state scheme Multipath Created through ELS I J A B C L D K

doc.: IEEE /0128r0 Submission Slide 28 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (3) Link state generation begAddrendAddrtree_leveloh_neighbor 1, oh_neighbor 2, …, oh_neighbor k begAddr: beginning address of the address block owned by the node (this is also the address assigned to the node itself) endAddr: ending address of the address block owned by the node tree_level: tree level of the node oh_neighbor i : one-hop neighbor of the node Format of Hello message Hello message

doc.: IEEE /0128r0 Submission Slide 29 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (4) Link state generation (cont.) Neighbor list begAddr 1 endAddr 1 tree_level 1 hops 1 begAddr 2 endAddr 2 tree_level 2 hops 2 …… begAddr n endAddr n tree_level n hops n Neighbor list

doc.: IEEE /0128r0 Submission Slide 30 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (5) Link state generation (cont.) Connectivity matrix menb 1 nb 2 nb 3 …nb n-2 nb n-1 nb n me--+-…-+- nb 1 -+-…+-- nb 2 -+…--- nb 3 -…+- …………… nb n nb n-1 -- nb n - Note: (1) The plus or minus sign (“+” or ”-“) at the cross cell of two nodes indicates they are or are not directly connected (i.e., they are or are not one-hop neighbors); (2) For bi-directional links, the matrix is symmetric, so only half of the matrix is needed as shown here. (3) Hop information can be calculated using the connectivity matrix. Here we have: 1-hop neighbors: nb 2, nb n-1, … 2-hop neighbors: nb 1, nb 3, … 3-hop neighbors: nb n-2, … 4-hop neighbors: nb n, …

doc.: IEEE /0128r0 Submission Slide 31 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (6) Data forwarding 1: func_nextHop(dst) 2: neighbor_found = search the neighbor list for the lowest (i.e., with the largest tree level) neighbor who is the ancestor of dst but is not my ancestor; 3: if neighbor_found//going down 4: next_hop = getOneHopNeighbor(neighbor_found); 5: return next_hop; 6: else if the destination is not my descendent//going up 7: found = is there a neighbor who has a tree level less than mine? 8: if found 9: hops2root = the minimum (hops + tree_level) found among neighbors that have a tree level less than mine; 10: minHops = the minimum hops found among neighbors that have a (hops + tree_level) of hops2root; 11: neighbor_found = select one of the neighbors that have a (hops + tree_level) of hops2root and a hops of minHops; 12: next_hop = getOneHopNeighbor(neighbor_found); 13: return next_hop; 14: else//should go up, but can’t 15: return no_next_hop; 16: end if 17: else//should go down, but can’t 18: return no_next_hop; 19: end if 20: end func

doc.: IEEE /0128r0 Submission Slide 32 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (7) Data forwarding (cont.) 21: func_getOneHopNeighbor(neighbor_found) 22: mark the hop_number of each neighbor as “infinity”; 23 current_hops = hop number of the neighbor_found; 24: while current_hops > 1 25: for each neighbor nbi with a hop_number of current_hops 26: for each neighbor nbj directly connected to nbi 27: hop_number of nbj = current_hops – 1; 28: end for 29: end for 30: current_hops = current_hops - 1; 31: end while 32: return one of the neighbors with hop_number of 1; 33: end func

doc.: IEEE /0128r0 Submission Slide 33 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (8) Sanity/consistency checking Approach 1 where, neighborLevel:the tree level of neighbor_found given in line 21 of the above pseudo code hops2Nb:hops to neighbor_found Let flag 1 = the up-down flag included in an incoming message vTreeLevel 1 = the virtual tree level included in an incoming message flag 2 = the up-down flag of the receiver of the message vTreeLevel 2 = the virtual tree level of the receiver of the message then it follows that:

doc.: IEEE /0128r0 Submission Slide 34 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (9) Note that, if the receiver calculates flag2 and vTreeLevel2 using only (maxHops – 1)-hop link state information (i.e., one hop less than that used by previous hop), then only the equal sign “=” should be applied in equation (2). Approach 1 (cont.) Sanity/consistency checking (cont.)

doc.: IEEE /0128r0 Submission Slide 35 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (10) Approach 2 Sanity/consistency checking (cont.) A more efficient way is to only include the up-down flag and the hops2Nb value in the message. The virtual tree level has the same bit size as an assigned address, but hops2Nb only needs several bits (e.g., 3 bits). Similarly we define: flag1 = the up-down flag included in an incoming message hops2Nb1 = the hop2Nb value included in an incoming message flag2 = the up-down flag of the receiver of the message hops2Nb2 = the hop2Nb value of the receiver of the message where, (flag1, hops2Nb1) are calculated using maxHops-hop link state information, but (flag2, hops2Nb2) are calculated using only (maxHops -1)-hop link state information. In this case, we should have:

doc.: IEEE /0128r0 Submission Slide 36 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (11) Link state maintenance  A node should broadcast several Hello messages with a TTL of maxHops if it detects its one-hop connectivity has changed due to link failures, link recoveries, or the detection of new neighbors.  A neighbor to which a transmission has failed is put in a probe list. –It is probed periodically using a timer (timer-driven probe) –It is also probed upon the reception of a data packet that takes the neighbor in the probe list as the next hop

doc.: IEEE /0128r0 Submission Slide 37 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (12) Link state maintenance (cont.)  The link is determined as down if it is not recovered after max_probe_num probes.  The link is considered recovered if –a MAC ACK of a probe (if the routing layer have access to status of MAC ACK) is received, or –any packet including the reply of a probe is received from that neighbor by the routing layer (or overheard by the MAC if overhearing is supported).

doc.: IEEE /0128r0 Submission Slide 38 March 2006 J. Zheng, Samsung CUNY TDLS: DLS Scheme (13) Link state maintenance (cont.)  The neighbor remains in the probe list if the link to the neighbor is down –It will be probed only be timer (it will not be used as the next hop of any data packet, so no data-driven probe). –The probe interval is increased after each probe, up to a maximum value max_probe_interval.

doc.: IEEE /0128r0 Submission Slide 39 March 2006 J. Zheng, Samsung CUNY ART/MART/TDLS: Simulations (1) Experimental setup  Topologies –49 nodes (7 x 7 grid) –100 nodes (10 x 10 grid) –196 nodes (14 x 14 grid) –400 nodes (20 x 20 grid) –784 nodes (28 x 28 grid)  3-hop link state  1 packet per second  Start one traffic flow between two randomly selected nodes each 10 seconds.  10% nodes in transmission/reception

doc.: IEEE /0128r0 Submission Slide 40 March 2006 J. Zheng, Samsung CUNY ART/MART/TDLS: Simulations (2) Simulation results (1)

doc.: IEEE /0128r0 Submission Slide 41 March 2006 J. Zheng, Samsung CUNY ART/MART/TDLS: Simulations (3) Simulation results (2)

doc.: IEEE /0128r0 Submission Slide 42 March 2006 J. Zheng, Samsung CUNY ART/MART/TDLS: Simulations (4) Simulation results (3)

doc.: IEEE /0128r0 Submission Slide 43 March 2006 J. Zheng, Samsung CUNY ART/MART/TDLS: Simulations (5) Simulation results (4)

doc.: IEEE /0128r0 Submission Slide 44 March 2006 J. Zheng, Samsung CUNY ART/MART/TDLS: Simulations (6) Simulation results (5)

doc.: IEEE /0128r0 Submission Slide 45 March 2006 J. Zheng, Samsung CUNY ART/MART/TDLS: Simulations (7) Simulation results (6)

doc.: IEEE /0128r0 Submission Slide 46 March 2006 J. Zheng, Samsung CUNY Highlights  Adaptive Block Addressing (ABA) –Auto-configuration –Avoiding “running out of addresses” problem –Extensibility  Meshed Adaptive Robust Tree (MART) –ART = ABA + Data forwarding + Tree Repair –Meshed ART Shorter path Robustness  Topology-based Distributed Link State (TDLS) – recommended approach –TDLS = ABA + Distributed Link State (DLS) –Simplicity No route discovery No route repair Bandwidth- and memory-efficiency –DLS Scalability Multiple paths and robustness Shorter path

doc.: IEEE /0128r0 Submission Slide 47 March 2006 J. Zheng, Samsung CUNY Thank you! Questions?