Describe active file transfer protocol (FTP).
What will be an ideal response?
FTP has two ways to transfer data: active and passive FTP. Traditionally, FTP uses the active process. FTP uses TCP ports 20 and 21. When your client sends an FTP request, it goes out on port 21. When your FTP server responds, however, it sends the data back using an ephemeral destination port and port 20 as a source port. Active FTP works great unless your client uses NAT. Since your client did not initiate the incoming port 20, your NAT router has no idea where to send this incoming packet. Additionally, any good firewall sees this incoming connection as something evil because it does not have anything inside the network that started the link on port 20.
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Which of the following statements about embedded operating systems is FALSE?
A) They can be found in a GPS device. B) They can run on simple hardware. C) They are very large. D) They have specialized, limited functions.
All desktops provide support for ECC and should be enabled or disabled through the system BIOS/UEFI
Indicate whether the statement is true or false
Which of the following languages uses the ampersand (&) for string concatenation?
A. Ada B. C++ C. C# D. Java
Structures may be passed to functions by ________.
a) passing individual structure members b) passing an entire structure c) passing a pointer to the structure d) all of these