1. Segmentation
2. Topology
3. Encapsulation
4. CRC
5. Plenum
6. TCP
7. Hub
8. Collision Domain
9. Bridge
10. Redirector
11. Pre-emptive Multitasking
12. Baseband
13. Backbone
14. Service
15. Router
16. IPAddress
17. Category 5e
18. UDP
19. Signals
20. Broadband

A. Electrical voltages, pulses of light, infrared, radio waves.
B. Media that carries one signal at a time.
C. Media that carries multiple signals at a time.
D. A 32-bit number used by the network layer.
E. The pattern or shape used to connect computers together.
F. Cable specifications of cable for Gigabit Ethernet
G. The error detection computation performed on the payload data of a packet.
H. Transmits data between networks at the network layer.
I. A connection-oriented protocol
J. A connectionless protocol
K. Media rated to be used in building's air space that does not
   produce toxic gases when burned.
L. A program that operates at the application layer for the benefit of
   a client or server.
M. Transmits data between segments or collision domains at the data link layer.
N. Part of a network that is constructed so that when two computers
   transmit packets at precisely the same time a collision occurs.
O. A program that runs in the background continuously.
P. NOS that supports time slicing to provide resources for many users,
Q. Relays packets to all ports and repeats them
R. The division of a lengthy data stream into segments sufficiently
   small for transmission over the network.
S. The process by which the protocols add their headers and footer to
   the request generated by the application.
T. A segment that joins multiple smaller segments and provides high
   capacity  access for data traveling between segments.