@INPROCEEDINGS {qun_icdcs08_2, author = {Haodong Wang and Bo Sheng and Chiu C. Tan and Qun Li}, booktitle = {{IEEE ICDCS} }, PAGES = {--}, TITLE = {Comparing Symmetric-Key and Public-Key based Security Schemes in Sensor Networks: A Case Study of User Access Control}, Address ={Beijing, China}, Month={June}, YEAR = {2008} } Abstract While symmetric-key schemes are efficient in processing time for sensor networks, they generally require complicated key management, which may introduce large memory and communication overhead. On the contrary, public-key based schemes have simple and clean key management, but cost more computational time. The recent progress of elliptic curve cryptography (ECC) implementation on sensors motivates us to design a public-key scheme and compare its performance with the symmetric-key counterparts. This paper builds the user access control on commercial off-the-shelf sensor devices as a case study to show that the public-key scheme can be more advantageous in terms of the memory usage, message complexity, and security resilience. Meanwhile, our work also provides insights in integrating and designing public-key based security protocols for sensor networks.