Inventor
SHUM KWAN
CN2 patents
Patents
2 patentsUS7920548B2Apr 5, 2011
Intelligent switching for secure and reliable voice-over-IP PBX service
HK APPLIED SCIENCE & TECH RES34 citations87
US7836488B2Nov 16, 2010
Authentic device admission scheme for a secure communication network, especially a secure IP telephony network
HK APPLIED SCIENCE & TECH RES2 citations56