What is the best security policy concerning this setup?
A. Network elements must be hardened with user ids and strong passwords. Regular security tests and audits should be performed.
B. As long as the physical access to the network elements is restricted, there is no need for additional measures.
C. There is no need for specific security measures on the network elements as long as firewalls and IPS systems exist.
D. The operator knows that attacks and down time are inevitable and should have a backup site.