[1] [1] K. Lu, G. Xiao, and I. Chlamtac, IEEE/ACM Trans. Networking 13, 187 (2005).

[2] [2] N. Sambo, A. Giorgetti, I. Cerutti, and P. Castoldi, IEEE Commun. Lett. 11, 820 (2007).

[3] [3] L. Wang, J. Zhang, G. Gao, Y. Liu, X. Chen, Y. Zhao, Y. Yao, and W. Gu, IEEE Commun. Lett. 12, 593 (2008).

[4] [4] J. Liu, G. Xiao, K. Lu, and I. Chlamtac, IEEE J. Sel. Areas Commun. 25, 27 (2007).

[5] [5] Y. Hua, Y. Lu, T. Zhao, Y. Ji, and B. Rao, Chin. Opt. Lett. 7, 978 (2009).

[6] [6] L. Pei, R. Zhao, T. Ning, X. Dong, Y. Wei, C. Xin, and Y. Ruan, Acta Opt. Sin. (in Chinese) 29, 308 (2009).

[7] [7] G. Kong, S. E, W. Deng, H. Guo, D. Zhang, and C. Chen, Chinese J. Lasers (in Chinese) 36, 134 (2009).

[8] [8] X. Yi, W. Chen, and W. Shieh, IEEE Photon. Technol. Lett. 18, 1448 (2006).

[9] [9] F. N. Khan, A. P. T. Lau, Z. Li, and P. K. A. Wai, IEEE Photon. Technol. Lett. 22, 823 (2010).

[10] [10] S. Arakawa, Y. Kanitani, M. Murata, and K. Kitayama, in Proceedings of IEEE Broadband Networks 341 (2005).

[11] [11] J. H. Lee, N. Yoshikane, T. Tsuritani, and T. Otani, J. Lightwave Technol. 26, 1217 (2008).