doc IEEE 802 19 yyxxxxr 0 November 2008

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Impact of IEEE 802. 11 n Operation On IEEE 802. 15. 4 Performance Authors: Date: 2008 -11 -02 Notice: This document has been prepared to assist IEEE 802. 19. 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. Submission Slide 1 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Abstract In this presentation, we evaluate the impact of IEEE 802. 11 n operation on IEEE 802. 15. 4 performance via test bed experiments. The IEEE 802. 15. 4 performance is measured in terms of packet loss rate and the latency for successfully delivered packets. Submission Slide 2 Mukul Goyal, U Wisconsin Milwaukee

November 2008 doc. : IEEE 802. 19 -yy/xxxxr 0 IEEE 802. 15. 4: Overview • A MAC/PHY layer protocol for low power, low data rate (< 250 kbps) wireless sensor applications • Based on CSMA/CA Submission Slide 3 Mukul Goyal, U Wisconsin Milwaukee

November 2008 doc. : IEEE 802. 19 -yy/xxxxr 0 The CSMA/CA algorithm in (unslotted) 802. 15. 4 • The source node backoffs for a random number of slots between 0 and (2^BE) – 1 – BE is Backoff Exponent • After the backoff, the source node does the clear channel assessment (CCA) • If the channel is not idle (CCA Failure), the source node increments BE and repeat the process up to 4 times – The initial BE value is 3 and max BE value is 5 Submission Slide 4 Mukul Goyal, U Wisconsin Milwaukee

November 2008 doc. : IEEE 802. 19 -yy/xxxxr 0 The CSMA/CA algorithm in (unslotted) 802. 15. 4 • If the CCA fails even after 4 th retry, the source node declares channel access failure (CAF) and abandons the packet transmission • If the CCA succeeds, the source node transmits the packet. • On receiving the packet, the destination optionally sends an acknowledgement back Submission Slide 5 Mukul Goyal, U Wisconsin Milwaukee

November 2008 doc. : IEEE 802. 19 -yy/xxxxr 0 Collisions and Retransmissions • If the packet or the ack suffers a collision, the source node waits for a certain time duration and then repeat the (backoff + transmission) process up to 3 more times. • If the ack is not received even after the 3 rd retry, the source node declares a collision failure and abandons the packet. Submission Slide 6 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Packet Loss in IEEE 802. 15. 4 • Channel access failure – channel access failure occurs after 5 back-to-back CCA failures during a try. • Collision failure – occurs after failure to receive the ack even after 4 tries. • Note that a channel access failure causes abandonment of packet transmission attempt even if 4 tries have not been made. Submission Slide 7 Mukul Goyal, U Wisconsin Milwaukee

November 2008 doc. : IEEE 802. 19 -yy/xxxxr 0 Impact of IEEE 802. 11 n operation on IEEE 802. 15. 4 Performance • IEEE 802. 15. 4 performance is measured in terms of the packet loss rate and latency for successfully delivered packets. • In the following graphs, we plot the increase in average loss rate/latency values for IEEE 802. 15. 4 nodes due to the presence of an IEEE 802. 11 n network. Submission Slide 8 Mukul Goyal, U Wisconsin Milwaukee

November 2008 doc. : IEEE 802. 19 -yy/xxxxr 0 Traffic in IEEE 802. 15. 4 Network • 15 nodes sending packets to the coordinator. • The packet size is 112 bytes. • Each node sends on average one packet per second (poisson distributed) for 15 minutes • IEEE 802. 15. 4 network uses a 3 MHz wide channel centered at 2425 MHz (Channel 15) • Power level: 10 d. Bm Submission Slide 9 Mukul Goyal, U Wisconsin Milwaukee

November 2008 doc. : IEEE 802. 19 -yy/xxxxr 0 Traffic in IEEE 802. 11 n Network • An iperf client sends a UDP stream to an iperf server over an IEEE 802. 11 n network • Power level 17 d. Bm • Packet size: 1470 bytes • Client generates traffic at rates 1, 2, 5, 10, 15, 20 Mbps. Submission Slide 10 Mukul Goyal, U Wisconsin Milwaukee

November 2008 doc. : IEEE 802. 19 -yy/xxxxr 0 IEEE 802. 11 n Channels Used • Scenario 1: Channel 1, 20 MHz wide, no overlap with IEEE 802. 15. 4 channel • Scenario 2: Channel 6, 40 MHz wide (extends towards channel 11), no overlap with IEEE 802. 15. 4 channel • Scenario 3: Channel 1, 40 MHz wide, extends into the channel used by IEEE 802. 15. 4 network • Scenario 4: Channel 4, 20 MHz wide, overlaps the channel used by IEEE 802. 15. 4 network Submission Slide 11 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 1: IEEE 802. 11 n on Channel 1, 20 MHz wide IEEE 802. 11 n IEEE 802. 15. 4 2412 MHz 22 MHz Submission 2425 MHz 3 MHz Slide 12 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 1: Impact of IEEE 802. 11 n Operation on IEEE 802. 15. 4 Loss Rate 0, 003 Increase in Loss Rate 0, 0025 0, 002 0, 0015 0, 001 0, 0005 0 1 Submission 2 5 10 15 IEEE 802. 11 n Traffic Load (Mbps) 20 Slide 13 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 1: Impact of IEEE 802. 11 n Operation on IEEE 802. 15. 4 Latency 2 Increase in Latency (ms) 1, 8 1, 6 1, 4 1, 2 1 0, 8 0, 6 0, 4 0, 2 0 1 Submission 2 5 10 15 IEEE 802. 11 n Traffic Load (Mbps) 20 Slide 14 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 2: IEEE 802. 11 n on Channel 6, 40 MHz wide IEEE 802. 11 n IEEE 802. 15. 4 2425 MHz 3 MHz Submission 2437 MHz 44 MHz Slide 15 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 2: Impact of IEEE 802. 11 n Operation on IEEE 802. 15. 4 Loss Rate 0, 007 Increase in Loss Rate 0, 006 0, 005 0, 004 0, 003 0, 002 0, 001 0 1 Submission 2 5 10 15 IEEE 802. 11 n Traffic Load (Mbps) 20 Slide 16 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 2: Impact of IEEE 802. 11 n Operation on IEEE 802. 15. 4 Latency Increase in Latency (ms) 2, 5 2 1, 5 1 0, 5 0 1 Submission 2 5 10 15 IEEE 802. 11 n Traffic Load (Mbps) 20 Slide 17 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 3: IEEE 802. 11 n on Channel 1, 40 MHz wide IEEE 802. 11 n IEEE 802. 15. 4 Submission 2412 MHz 2425 MHz 3 MHz 44 MHz Slide 18 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 3: Impact of IEEE 802. 11 n Operation on IEEE 802. 15. 4 Loss Rate 0, 03 Increase in Loss Rate 0, 025 0, 02 0, 015 0, 01 0, 005 0 1 Submission 2 5 10 15 IEEE 802. 11 n Traffic Load (Mbps) 20 Slide 19 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 3: Impact of IEEE 802. 11 n Operation on IEEE 802. 15. 4 Latency 7 Increase in Latency (ms) 6 5 4 3 2 1 0 1 Submission 2 5 10 IEEE 802. 11 n Traffic Load (Mbps) 15 20 Slide 20 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 4: IEEE 802. 11 n on Channel 4, 20 MHz wide IEEE 802. 11 n IEEE 802. 15. 4 2425 MHz 2427 MHz Submission 3 MHz 22 MHz Slide 21 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 4: Impact of IEEE 802. 11 n Operation on IEEE 802. 15. 4 Loss Rate 0, 4 Increase in Loss Rate 0, 35 0, 3 0, 25 0, 2 0, 15 0, 1 0, 05 0 1 Submission 2 5 10 15 IEEE 802. 11 n Traffic Load (Mbps) 20 Slide 22 Mukul Goyal, U Wisconsin Milwaukee

doc. : IEEE 802. 19 -yy/xxxxr 0 November 2008 Scenario 4: Impact of IEEE 802. 11 n Operation on IEEE 802. 15. 4 Latency 100 Increase in Latency (ms) 90 80 70 60 50 40 30 20 10 0 1 Submission 2 5 10 15 IEEE 802. 11 n Traffic Load (Mbps) 20 Slide 23 Mukul Goyal, U Wisconsin Milwaukee