多項選擇題The Schuyler and Livingston Iron Works has been working on getting its network security under control. It has set up VPN with IPSec links to its suppliers. It has installed network vulnerability scanners to proactively identify areas of weakness, and it monitors and responds to security events as they occur. It also employs extensive access control lists, stateful firewall implementations, and dedicated firewall appliances. The company has been growing very fast lately and wants to make sure it is up to date on security measures.Which two areas of security would you advise the company to strengthen? （）

A. intrusion protection
B. identity
C. secure connectivity
D. security management