19. Which of the following statements about firmware are true? (Choose three.)

a.Sometimes a software update requires a firmware update before it can function properly.

b.It is not possible to test firmware for security breaches since updates are pushed from the OEM.

c.Firmware updates need to be tested like any other patch, service pack, or update.

d.When a firmware update is announced, you should carefully read the release notes to understand potential changes before installing it.

20. Many of your companys employees use their own wireless devices for company business and frequently bring those devices to the office. You need to ensure that devices that are neither corporate-owned nor corporate-controlled have the latest virus definition files before they are permitted access to the companys resources. Which of the following will be the most effective means of assuring the compliance of such devices?

a.NAC

b.MOU

c.IPsec

d.AUP

21. You have been called to diagnose a network problem at an elementary school built in 1945. Each classroom has one cable drop. The walls are all masonry, so to provide adequate Wi-Fi coverage to all classrooms, a consumer-grade Internet gateway router has been installed in each classroom. To facilitate central administration, each of these routers has its WAN port taped off and is connected back to the buildings main unmanaged network switches via one of its four LAN ports. DHCP is provided by a centralized server, so DHCP has been disabled on each of the routers. Most of the teachers use wireless laptops or tablets, but a few have wired desktop computers or printers, and those are wired to other LAN ports on that teachers router. Everything had been working fine for months, but suddenly, network traffic has slowed to a crawl, and all the activity lights on the main network switches are blinking synchronously and continuously. Which of the following situations could best explain these symptoms?

a.The DHCP server is giving out an inaccurate DNS.

b.A laptop is simultaneously connecting wired and wirelessly.

c.There is a duplicate IP address on the network.

d.Two of a routers LAN ports have been looped.