4. The text below shows the reply sent from a server in response to an HTTP GET message as captured by Wireshark.

HTTP/1.1 200 OK

Date: Fri, 27 Jan 2023 21:23:36 GMT

Server: Apache/2.4.6 (CentOS) OpenSSL/1.0.2k-fips PHP/7.4.33 mod_perl/2.0.11 Perl/v5.16.3

Last-Modified: Tue, 01 Mar 2016 18:57:50 GMT

ETag: "a5b-52d015789ee9e"

Accept-Ranges: bytes

Content-Length: 2651

Keep-Alive: timeout=5, max=100

Connection: Keep-Alive

Content-Type: text/html; charset=UTF-8

[HTTP response 1/1]

[Time since request: 0.035874000 seconds]

[Request in frame: 784]

[Request URI: http://gaia.cs.umass.edu/]

File Data: 2651 bytes

Line-based text data: text/html (68 lines)

More document text follows, though not shown here.

Answer the following questions, indicating where in the message above you find the answer.

(a) Was the server able to successfully find the document or not? What time was the server reply provided?

(b) When was the document last modified?

(c) How many bytes are there in the content being returned?

(d) What are the first 5 bytes of the document being returned?

5. Obtain the HTTP/2 specification (RFC 7540). Answer the following questions:

(a) What are the fields in the frame header, and how long is each field?

(b) What is the maximum length of the frame payload?

(c) What is the error code for ENHANCE_YOUR_CALM and what does this error code mean?