How does NAT work?
What will be an ideal response?
When a user workstation on a company local area network sends a packet out to the Internet, NAT replaces the IP address of the user workstation with a corporate global IP address. In fact, all packets that leave the corporate network contain this global IP address. Thus, the only IP address that anyone sees outside of the corporate network is the one global IP address. If all packets from all workstations leave the corporate network with the same IP address, how do the responses that come back from the Internet get directed to the proper machine? The NAT software maintains a cache listing of all IP packets that were sent out and who sent each packet. When a response comes back, NAT checks the cache to see who originally sent the request. When NAT finds the match, it removes the global IP address, reinserts the user workstation's IP address, and places the packet on the corporate network.?What happens if a packet arrives at the corporate NAT software and there is no cache entry with a matching outgoing request? In this case, the packet is destroyed. Apparently, someone has sent a packet to the corporate network that was not requested by a corporate workstation. There is one exception to this rule: If the company is supporting a server, such as a Web server, a packet may originate from a user somewhere out on the Internet. When the Web page request packet arrives at the NAT software, the IP address where the packet originated will not match any IP addresses in the local cache. Before the NAT software destroys the packet, it examines the message's destination port number. If the packet is a request for a Web page from the corporate Web server, the NAT software lets the packet in.
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In the following pseudocode which uses recursion to find the factorial of a number, which is the recursive case?
``` Module main() Declare Integer number Declare Integer numFactor Display "Enter a non-negative integer:" Input number Set numFactor = factor(number) Display "The factorial of ", number, " is ", numFactor End Module Function Integer factor(Integer n) If n == 0 Then Return 1 Else Return n * factor(n - 1) End If End Function ``` a. n == 0 b. n * factor(n - 1) c. factor(n - 1) d. n > 0
The font size of a datasheet cannot be changed
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Which of the following is NOT a problem with duplicated data?
A. It is error-prone. B. It limits query capabilities. C. It limits reporting capabilities. D. It creates its own one-to-many relationships.