A four-person design studio runs its whole office network behind the single router its ISP supplied, and switches on that router’s packet-filtering rules. Nothing else is bought. Which topology has the studio deployed?

Answer

Screening router

Options - A. Screening router - B. Single bastion T - C. DMZ - D. Host-resident firewall Why - A. Correct — the only device between the two networks is a router that filters, which is the rung above per-host software and the standard answer for a small office or home office. - B. A single bastion T is a firewall DEVICE with a third interface leading to a DMZ, not a router, and it suits medium to large organisations. - C. A DMZ is a network segment sitting between two firewalls or on a third interface. It is not a device and not a topology on its own. - D. Host-resident firewalls are software on the individual machines. There is no single device between the networks at all. Every distractor is a real term from the same taxonomy, so the discrimination is: how many devices, of what kind, and for what size of organisation.

Stallings & Brown, Computer Security 5e, ch9 sections 9.4-9.5