Let’s test your knowledge of important topics such as SYN attacks and VLANs for your Cisco CCNA, CCNP, and CCENT exams, as well as the CompTIA Security+ and Network+ certification exams!

CCNA / CCENT / CompTIA Network+ Certification:

Host A and Host B are in the same VLAN. Host C and Host D are in a different VLAN. Host A sends a broadcast. How many other hosts will receive it?

A. Zero

B. One

C. Two

D. Three

Answer: B. The other host in the same VLAN, Host B, will receive it. Broadcasts are not forwarded to other VLANs.

Security+ Certification:

Briefly describe a "SYN attack".

Answer: The intruder will generate a series of SYN requests, and the soon-to-be-victimized network device sends a SYN-ACK in response. The device then waits for an ACK, but that never comes. These unfinished connections result in the network device not being able to accept SYN request from legitimate network hosts, since its buffers will be overwhelmed with the false (and unfinished) requests.

CCNP Certification / BSCI Exam:

If an IPv6 address begins with "FF", what type of address is it?

A. broadcast

B. unicast

C. multicast

D. MACcast

Answer: C. That's a multicast. There's no such thing as a MACcast. But there should be. ;)

CCNP Certification / BCMSN Exam:

Short answer: What interface-level command takes a port operating at L3 and places it into L2 operating mode?

Answer: switchport. To change the port back to a routed port, use no switchport.

CCNP Certification / ISCW Exam:

Short answer: You're going to write a policy map that will be applied to a Serial interface running at T1 speed. By default, how much bandwidth can you assign in that policy?

Answer: The speed of a T1 line is 1544 kbps, but by default only 75% of that bandwidth can be distributed in a policy map - that's 1158 kbps (1544 * .75).