Answer:
The code is given as below: The input and output is as given for one case.
Explanation:
echo -e "Enter A, B or C : \c" #Printing the line on the screen
read -rN 1 test #read the character in the variable test
echo
case $test in #Setting up the case structure for variable test
[[:lower:]] ) #checking all lower case letters
echo You did not enter A, B or C;;
[D-Z] ) #checking upper case letters from D to Z
echo You did not enter A, B or C;;
A ) #Condition to check A
echo You entered A;;
B ) #Condition to check B
echo You entered B;;
C ) #Condition to check C
echo You entered C;;
esac #Exiting the case structure
Answer:
MDF, IDFs
Explanation:
MDF or main distribution frame is a cable racking system in networking used to interconnect and manage information technology connecting cables from itself to multiple IDFs.
The IDF or intermediate distribution frame, on the other hand, are cable racks that holds or stacks networking devices together and connects it cables to a central MDF rack.
A scenario of this connection is IDFs mounted on various floors on a building and all connected to one MDF.