The answer is firewall. It is a network security device that observes inbound and outbound network traffic and chooses whether to allow or block specific traffic based on a well-defined set of security rules. Firewalls have been a first line of protection in network security for over 25 years. The firewall present a barrier between measured and secured internal networks that can be trusted and untrusted outside networks, for example the Internet. A firewall can be software, hardware, or even both.
The answer is (b) Rigid-metal
If you are installing a conduit for a mast service, the type of conduit to be used should be a rigid metal type. Among the three types of steel conduit, the most preferable to install is the rigid metal type instead of an intermediate metal conduit and electrical metallic tubing. Rigid metal conduit is a ferrous metal.
Change is what is left over
ex. the cashier tells you "here is your leftover change sir/ma'am "<span />
Answer:
d. All of the above
Explanation:
Physical layer is the lowest layer of the OSI reference model that deals with the setup of physical connection to the network and with transmission and reception of signals.
Full duplex (FDx) is a bidirectional type of communication system where two end nodes send and receive data signals at the same time, and a single carrier is simultaneously used for dual communication.
To send or receive data, the participating nodes in a Full Duplex system do not have to wait for a free carrier/medium. It employs a medium that has at least two internal channels - one for sending and one for receiving.
Based on the above explanations, options A, B and C are valid and are correct ways to accomplish full-duplex (FDX) digital communications on guided medium at the physical layer (OSI Layer 1). There all of them are correct.