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Q15Using APIsMultiple answers

Refer to the exhibit. An application uses an API to periodically synchronize a large dataset. Based on the HTTP message sequence shown, which statements are true about the caching behavior in this scenario? (Choose two.)

Question exhibit
Select 2 answers.
← → navigate · a answer
Community votes
A
50% (2)
D
50% (2)
B
0% (0)
C
0% (0)
E
0% (0)
Discussion · 9
17
A and D are the correct ones here. Explanation: The HTTP 304 Not Modified client redirection response code means there is no need to resend the requested resources. It is an implicit redirection to a cached resource. This occurs when the request method is safe, like a GET or a HEAD request, or when the request is conditional and uses a If-None-Match or a If-Modified-Since header. The matching 200 OK response would have contained the headers Cache-Control, Content-Location, Date, ETag, Expires, and Vary. Whenever the resource is updated on the server, the ETag header changes to reflect the content of the new version of the resource. The Etag value does not change during the whole transaction between client and server, confirming A and D as the answers here.
6
A&D are the correct answer.
5
Two 200 responses with the same ETag
3
Agree with 'A & D' as the correct answer
2
D & E 304 response will not send the resources because the resource is not changed. The HTTP 304 Not Modified client redirection response code means there is no need to retransmit the requested resources. It is an implicit redirection to a cached resource. This happens when the request method is safe, like a GET or a HEAD request, or when the request is conditional and uses a If-None-Match or a If-Modified-Since header.
2
E is incorrect. messages 3 and 5 are NOT equivalent at all. Message 5 is asking for a new copy if the message changed after 11 GMT. Message 3 requests a new copy if the message chaged after 12 GMT. Correct answer is A and D.
2
No. No partial data was sent in that case. 304 means not modified and only says that the data wasn't changed. So no data from the data set is transmitted.
1
To me it is obvious that A & D are correct indeed. But isn't C also correct?
A, D 1
Selected Answer: AD A and D are the correct answers. C - The data hasn't changed during the process because the validators are the same (If-None-Match and If-Modified-Since). Also, A is correct since #1 has received the HTTP/1.1 200 OK and #5 too, with the same Last-Modified and ETag values.