Which Network Operating System (NOS) security practices are commonly used when planning
server management? (Select three)

A.
disable FTP and SSH

B.
install hardware and software firewalls

C.
disable unused TCP/IP service ports

D.
use easy to remember password

E.
enforce regular password changes

Explanation:
Industry Standard Architecture – Student Guide 2 – Page 200:
Working with the server management plan and the service plan
Change passwords regularly.
Establish a regular schedule for password changes.
Do not use the same password for individual and administrative accounts.
Follow standard password construction recommendations for length and complexity.
Disable unused or unneeded service ports.
Security risks exist at well-known network service ports if they remain open.
Telnet is a major security risk for administrative access due ease of password theft. Use secure
shell (SSH) if remote access is necessary.
Disable file transfer protocol (FTP) if it is not needed. If it is needed, never use root or
administrator passwords when transferring files since these are transferred as plain text.
Install hardware and software firewalls for Internet protection.
These allow the administrator to control which server ports are open to Internet traffic.
Firewalls can also detect intrusion attempts.
Install virus protection.
Most viruses are written for the Windows operating system, making that platform especially
vulnerable.
New viruses and worms are also showing up for systems running the Linux operating system as
well.