Alice sends an email to Bob via webmail. Bob receives it via webmail. Indicate the minimum number possible of TCP connections necessary for the sending and receiving Alices e-mail to Bob.

Group of answer choices

3

4

6

1

0

A host must resolve the symbolic name engineering.vanderbilt.edu, the IP address of which is not known. If the name server hierarchy has 3 levels, indicate the number of DNS messages that, in the worst case, will circulate on the internet to resolve this symbolic name, if (a) a recursive resolution is used at each level, or (b) an iterative resolution.

Group of answer choices

(a) 8 (b) 8.

(a) 6 (b) 6.

(a) 6 (b) 8.

(a) 8 (b) 6.

None of these answers.