1. TinySec: Performance Characteristics Chris K :: Naveen S :: David W January 16, 2004

2. This Talk Recent results Recent results Measurements on Mica2s (TOS 1.1.2) Measurements on Mica2s (TOS 1.1.2) Latency Latency Bandwidth Bandwidth Power Power Stress testing Stress testing Hardware crypto comparison & implications Hardware crypto comparison & implications 802.15.4 (e.g. CC2420) 802.15.4 (e.g. CC2420)

3. TinySec Review: How & Why Link layer security mechanism Link layer security mechanism Hop-by-hop, not end-to-end Hop-by-hop, not end-to-end Better support for aggregation Better support for aggregation Enables higher level keying protocols Enables higher level keying protocols Low overhead security in software Low overhead security in software Cryptographic checksum (MAC) Cryptographic checksum (MAC) Ensures integrity Ensures integrity Enforces access control Enforces access control Optional encryption Optional encryption

4. TinySec Performance Characterize Overhead: Energy, Latency, Bandwidth. Characterize Overhead: Energy, Latency, Bandwidth. Factors for TinySec overhead Factors for TinySec overhead Computation Computation Larger packet sizes Larger packet sizes Can predict overhead caused by packet sizes Can predict overhead caused by packet sizes Measurement goal: Show computation overhead is minimal Measurement goal: Show computation overhead is minimal Note: crypto HW only reduces computation overhead Note: crypto HW only reduces computation overhead

5. Packets & Predicted Overhead Old packet (CRC): +7 b Authentication Only (TinySec-Auth): +8 b Authentication, Encryption (TinySec-AE) : +12 b IV Overhead (b) Total Size (b) Xmit time (ms) IncreaseCRC396326.2-- TinySec-Auth406426.61.5% TinySec-AE446828.88%

6. Latency Test Setup Test purpose: Test purpose: Measure latency at different hopcounts Measure latency at different hopcounts Determine difficulty in adding TinySec to existing application Determine difficulty in adding TinySec to existing application Integrate with SystemC Integrate with SystemC Successfully transmitted 70,000+ packets: Successfully transmitted 70,000+ packets: Our stress test Setup : Setup : 4x9 grid in Woz of Mica2s 4x9 grid in Woz of Mica2s Landmark routing code from midterm demo Landmark routing code from midterm demo 200 measurements per hopcount 200 measurements per hopcount LM A B BS

7. Latency

8. Latency: Byte Times

9. Energy Test Setup Single mote transmitting a packet Single mote transmitting a packet Measure voltage drop with oscilloscope Measure voltage drop with oscilloscope

10. Energy +3% +10%

11. Bandwidth Test Setup Vary number of senders Vary number of senders Each sender sends as fast as it can Each sender sends as fast as it can Measure number of packets successfully received in a time period Measure number of packets successfully received in a time period

12. Bandwidth TinySec-Auth: same throughput TinySec-AE: 6% less throughput

13. Performance Summary Predicted (packet size only) Latency Overhead BW Overhead Energy Overhead CRC (No TinySec) ------------ TinySec- Auth 1.5%1.7%Negligible3% TinySec- AE 8%7.3%6%10%

14. TinySec Status New version working with 1.1.3 stack New version working with 1.1.3 stack To use: TINYSEC=true To use: TINYSEC=true Suggestion: base new stacks off of TinySec stack Suggestion: base new stacks off of TinySec stack