Since you are interviewing for a position in which you will make recommendations to customers about protecting their company's network, I'm curious about what you do to protect your own network at home.
"Funny you should say that. Many of the practices I recommend to secure a company's network I learned while setting up my personal network. These include using the latest versions of the network hardware and software with the most current virus protection, maintaining a strong firewall, and implementing strong user authentication, or passwords, which are updated frequently. I also monitor the network traffic on my home system to determine if any threats exist. To date, I have discovered many attacks on my system from sources around the world, but so far none of them have been successful at breaching my network."
This is a 'trick' question which many applicants won't expect. You need to be prepared for this and should answer it honestly.
If you do not protect your own home as you would a client's network, then suggest to the interviewer the main reason being is that you don't work from home.
"That's a great question and one I've never been asked before. I take my family's security as serious as I do that of the companies I work with. My home network has all the same security measures I recommend to my customers at work. These include a strong firewall, user authentication, access control, and frequent audits. I also upgrade my network hardware, such as routers and NICs periodically as new security features are released."
