Let's say there's 2 HTTP requests send to http server using the same underlying TCP connection almost at the same time.
How http server identify this two HTTP requests correctly(OR how http server parse these TCP connection bytes into 2 HTTP requests correctly) ?
For example :
request 1 : 2000 bytes
request 2 : 2000 bytes
http client http server
|---------req1 1000byte------->|
|---------req2 1000byte------->|
|---------req1 200byte-------->|
|---------req2 1000byte------->|
|---------req1 800byte-------->|
Related
Below is the configured thread group
Thread Group
|
|--> HTTP SAMPLE
I am opening 5 threads in 5 seconds with loop count is 5. It means in each thread 5 HHTP request will be sent, so total 25 request.
Thread 1 : TCP CONNECTION OPENED --> HTTP REQUEST SENT ---> HTTP RESPONSE RECEIVED.
Question: After receiving response whether TCP connection will be closed and again TCP connection will be opened and then HTTP request will be sent?
Or once response is received in same TCP connection next HTTP request will be sent?
It depends on what do you set in the HTTP Request sampler, if you tick Use KeepAlive box - then JMeter will send Connection header with the value of keep-alive
it means that the underlying TCP connection will remain open and the next HTTP Request sampler(s) will be reusing this connection.
If you untick the box JMeter will send Connection header with the value of close and next HTTP Request sampler will re-establish the connection.
You need to check what's going on in reality using your browser developer tools or an external sniffer tool like Wireshark and configure JMeter to behave exactly like the real browser does
if an HTTP client reaches a website through a proxy (not reverse proxy) server, what are the actual HTTP request and its parameters that are sent from this client host to the internet?
for example:
Proxy Server: www.proxy.com:80
Target website: www.website.com:8081
Does the HTTP client send the following Get request?
Get http://www.proxy.com:80
Host: www.proxy.com:80
OR
Get http://www.website.com:8081
Host: www.website.com:8081
if the first case is true, How can the proxy know what is the actual destination to forward this request?
otherwise, if the second is true, how can the request actually reach the proxy host machine?
When you want to issue a GET request to http://www.example.com:8081/index.html, the browser connects to www.example.com:8081 and sends the following request:
GET /index.html HTTP/1.1
Host: www.example.com:8081
Now when a proxy is configured, say www.proxy.com:80, the browser will connect to www.proxy.com:80 instead, and issue the following request:
GET http://www.example.com:8081/index.html HTTP/1.1
Host: www.example.com:8081
So when a proxy is configured, the HTTP client connects to the proxy instead of to the target server, and sends the request using the absolute URI.
The client doesn't have to change the HTTP request for it to be sent to a proxy. It has to change the TCP headers.
The screenshot below shows a HTTP request sent from my browser to a proxy, as you can see nothing in the HTTP request itself specifies the proxy.
How this works is the browser/client will issue a HTTP GET request, which will then be forwarded to the TCP/IP stack and wrapped in a TCP header. The TCP header is where the destination is specified (proxy or otherwise).
Http proxy server can read http headers.
Whenever we use http proxy the destination address in the tcp packet(originating from client) has destination address of proxy server..
When the proxy server receives the tcp packet it can read the http headers(which is present in tcp packet payload) the http headers contains the actual destination for the packet.. using this information the http proxy server can forward the packet to actual destination.
Source : https://www.ibm.com/support/knowledgecenter/SSBLQQ_9.1.0/com.ibm.rational.ritpp.install.doc/topics/c_ritpp_advanced_proxy.html
We are trying to make a secure communication between our embedded system and web server.Firstly we implement HTTP connection to in our microcontroller. I am just connecting to 80 port of my web server and send simple GET request to this port as example below :
GET /foo.php?msg=test HTTP/1.1
HOST: foo.com
My questions is,How we will turn this to HTTPS ? Which port i should connect ?
Will be any difference on structure of GET request above ? Will i have to do some encryption manually or connect to "https" link instead "http" is enuogh for secure communication.
Thanks for any information
The only difference between a HTTP request and a HTTPS request is that the first is send over a plain TCP connection while the other is send over a TLS connection, i.e.:
with HTTP you establish a TCP connection and send the request over this connection
with HTTPS you establish a TCP connection, upgrade this connection to TLS (including proper certificate validation etc!) and then send the same request as you did with HTTP over this connection.
Apart from that I recommend to either use an established library for HTTP or carefully read the standard. Although HTTP looks simply it is actually not and there are many questions here where users try to do a simply HTTP request and trip over behavior they did not expect.
For example in your case the server might send the response with chunked encoding, with content-length or simply end it with connection close. And it might wait for further requests on the same connection since HTTP/1.1 implicitly enables HTTP keep-alive. Does your code really account for all these cases?
Suppose I initiate a TCP connection for HTTP request and response. After the completion of three way handshaking process, I now send a request to the server for a HTTP packet with SYN flag set. The server responses to my request with ACK flag. Upon completion of the response, it will send me a FIN flag. Now how can I determine the size of the packet that the server send me during the request and response? Is there any process to do so?
Suppose I initiate a TCP connection for HTTP request and response. After the completion of three way handshaking process, I now send a request to the server for a HTTP packet with SYN flag set.
No you don't. The SYN was in the first packet sent in the three-way handshake. That's done. At best you will be piggy-backing the HTTP request on the final ACK packet of the connect handshake.
The server responses to my request with ACK flag.
No, the server responds to your HTTP request with an HTTP response. The ACK is irrelevant at the HTTP level.
Upon completion of the response, it will send me a FIN flag.
No it won't, unless you're speaking HTTP 1.0 or you have set the Connection: close header. Otherwise it will keep the connection open for HTTP keepalive.
Now how can I determine the size of the packet that the server send me during the request and response? Is there any process to do so?
The server didn't send you anything during the request. The size of the response body is given by the Content-length header or the sum of the chunked-encoding section sizes if that's used. You need to read the HTTP 1.1 RFC about this, it's non-trivial.
You also need to stop confusing HTTP with TCP. HTTP is an application protocol layered on top.
Protocol used: HTTP 1.1
Header includes 'Transfer-Encoding: chunked'
On sending subsequent requests (same request to the same server), containing 'Transfer-Encoding: chunked', I see new TCP socket being opened for each request.
Should the same socket not be used for requests? Why is the socket being terminated each time?
Note:
Requests sent using fiddler