The chief security officer (cso) of the exam company, which specializes in hosting online examinations, is concerned about the security posture of the data and voice network. the company currently has a firewall it uses to connect to the internet, and employees authenticate to the lan using a user id and password. there are no other network security controls in place. you are a network administrator responsible for all network platforms and services. what recommendations would you provide the cso that would increase the security posture of the data network?