HTTP Protocol

The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems. Hypertext is structured text that uses logical links (hyperlinks) between nodes containing text. HTTP is the protocol to exchange or transfer hypertext. HTTP functions as a request-response protocol in the client-server computing model. HTTP is designed to permit intermediate network elements to improve or enable communications between clients and servers. HTTP is an application layer protocol designed within the framework of the Internet Protocol Suite; it presumes an underlying and reliable transport layer protocol.

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HttpURLConnection getInputStream throws below errors sometimes -

java.lang.RuntimeException: Server returned HTTP response code: 500

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Here is the part of callstack -

09:05:02,198 ERROR [stderr] (http-/111.222.333.444:11800) Server returned HTTP response code: 500 for URL: https://111.222.333.444:11800/xyz/myapp/3.0/urn:name:ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJ
09:05:02,198 ERROR [stderr] (http-/111.222.333.444:11800)   at
09:05:02,199 ERROR [stderr] (http-/111.222.333.444:11800)   at

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This is a how my code looks like. This is not a client code. This runs on server like Tomcat -

private void getResult(HttpURLConnection urlconnection,
            String result) {
        BufferedReader bufferedReader;
        String line;
        try {

            bufferedReader = new BufferedReader(new InputStreamReader(

            while ((line = bufferedReader.readLine()) != null) {
                result += line;

        } catch (Exception ex) {
            String error = String.format("Invalid InputStream, %s",



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The URL that I have prepared looks like below -


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Can this be java problem or server is responsible for this? What could be the problem?
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Hi Experts,

I'm looking to modify the below to be an update instead of a select.
however not sure where do I put in the body param as specified below

Function GetDataFromCASPIO1()
    Dim objHTTP As New WinHttp.WinHttpRequest
    Dim docXML As MSXML2.DOMDocument
    Dim ResponseText As String
    Dim curNode As IXMLDOMNode
    Dim oNodeList As IXMLDOMSelection
    Dim s As String

    Set docXML = New MSXML2.DOMDocument

    Set objHTTP = New WinHttp.WinHttpRequest
    URL = ""
    objHTTP.Open "POST", URL, False
    objHTTP.SetRequestHeader "Content-Type", "application/x-www-form-urlencoded"

    ResponseText = Right(objHTTP.ResponseText, Len(objHTTP.ResponseText) - 17)
    access_token = Left(ResponseText, InStr(ResponseText, """") - 1)
    'Debug.Print access_token

    Set objHTTP = New WinHttp.WinHttpRequest

    URL = "{""limit"":10000,""where"":""visit_date>=GetDate()-7""}"

    '''objHTTP.Open "GET", URL, False
    objHTTP.Open "Put", URL, False
    objHTTP.SetRequestHeader "Accept", "application/xml"
    objHTTP.SetRequestHeader "Content-Type", "application/json"
    objHTTP.SetRequestHeader "Authorization", "Bearer " + access_token

    'Debug.Print objHTTP.Status
    'Debug.Print objHTTP.ResponseText

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Found these meta tags to ensure a page always reloads.

<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="Cache-Control" content="no-cache">
<meta http-equiv="Expires" content="0">

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Seen some pages where, despite having them, the cache still is used.

What can you recommend to add to these to be sure that the page arrives fresh each time?


How do I send a http request to a webserver using post without a web browser.

IE this will come from a script, what does the script look like?

I am trying to connect to a secure VAN and push and pull files over a secure connection.  As we are trying to set it up, the people at the VAN are getting this error.

Error Message:

AS2 Outbound has a HTTP proxy server to connect through.Probably error while connecting to proxy : [Error sending document over http to host [http://X.X.213.93], status code [405], reason [Method Not Allowed], response from server [<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "">< html xmlns="">< head>< meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"/>< title>405 - HTTP verb used to access this page is not allowed.</title>< style type="text/css">< !-- body{margin:0;font-size:.7em;font-family:Verdana, Arial, Helvetica, sans-serif;background:#EEEEEE;} fieldset{padding:0 15px 10px 15px;} h1{font-size:2.4em...]]


Sending of document [167499846.edi] to [http://X.X.213.93] FAILED

Any ideas of what I am missing or doing wrong?  The X.X.213.93 is the public IP of my machine receiving the files.

Need to write a script which:
1. Download the json file (curl request)
2. Rename the file to  YYYYMMDDHHMM_lng.xml
3. Push it to a shared folder (for example //
Hi Experts

I am working on a wagtail project(like django-cms) I get this error when I run python3 runserver

code 400, message Bad request syntax 
  You're accessing the development server over HTTPS, but it only supports 

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I had changed SECURE_SSL_REDIRECT=FALSE and tested it still i get this same error. I had disabled cache in chrome.

 I had deactivated chorme caching in registry  by following steps.
Deactivate Chrome Cache in the Registry

Open Registry (Start -> Command -> Regedit)

Search for: HKEY_CLASSES_ROOT\ChromeHTML\shell\open\command

Change the part after ...chrom.exe" to this value: –disable-application- cache –media-cache-size=1 –disk-cache-size=1 — "%1"

Example: "C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" - disable-application-cache –media-cache-size=1 –disk-cache-size=1 — "%1"

I had also tried disable cache from chrome developer tools network -disable cache.

I had also tried by clearing cache from hsts on chrome.

I had also tried from incognito window on chrome. But still I get the same error

It is an Ubuntu machine on AWS(accessed by putty from windows pc).

I access from outside (windows pc - local pc )through http://54.23x.9x.17:8000 I am not able to resolve this error.

I had tried on some other machine.  I got the following error on console for Linux Ubuntu

it is changing to https instead of http and I got "GET / HTTP/1.1" 301 0 on console window

Please help me in resolving this error.

With Many Thanks, Bharath AK
CNAME Record caused my emails to fail.

I hosted 2 emails at RackSpace for my domain, and verified they worked fine. This required me to update the MX records where I host my domain.


Then, before I could create a website, I was allowed by my partner to point my domain at his website.

The redirect worked once I created a CNAME record. brings up the site at

But the emails stopped working.

The error is "553 Relaying disallowed"

I called RackSpace and they said it's because the MX records at the, where points at, are pointing to Zoho (a major email provider).

So, my question is...

If I move my two emails from RackSpace to Zoho, can I have a solution where

1) domain forwarding is working ( brings up the site at
2) emails work as well (both ( emails work again)



Or, is there another way to configure this?

Why can I not update the URL in the browser?

I update QueryString and remove a malicious parameter. But, after executing the following code:


Still see that bad domain.

I may be fighting development automation inside my own project;

I paste the following into the browser...

My code captures the goto parameter and removes it from the QueryString. I call the RewritePath() function above, and see the following in the browser

I have no problem with the introduction of
but I do have a problem that the sub-domain re-appears.


I even created a copy of QueryString, made the deletions on the sanitized version. But that also fails.

Need to Redirect after removing one or more query string params.

I am using a whitelist to remove dangerous query string params, and when done, need to redirect to whatever is left in the  query string.

I understand things may break, but am okay letting our website's existing default behavior handle it.

What is the exact command to redirect?

ActionExecutingContext filterContext is the input param of the ActionFilterAttribute

        public override void OnActionExecuting(ActionExecutingContext filterContext)

and after removing the faulty query string params from:


I am ready to redirect.


Please complete the the above parameter for Redirect()

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I have a web application built in The home page is "main.aspx". I have x3 other websites that are directing traffic to the this website...the redirects are pointed to the main.aspx page. How can I capture which site the traffic is coming from? I'm thinking something with the headers. I would really like to capture the referring url or something that is unique.
I have Tomcat 8.0.35 running, web application running from IntelliJ IDEA 2017.3.3 (build successful and WAR deployed) but the browser (I tried with Chrome, Firefox, and IE) is showing HTTP Status 404 when I try to access http://localhost:8080/ or

I built my web application with Maven as WAR. The WAR file was successfully deployed in Tomcat's "/webapps/ROOT" directory and "index.html" and "index.jsp" are there and at the end of the deployment the browser page is open.

Tomat is configured to default ports: 8080, 8081, 8009.
what are difference between http post and get, as far as what/how data is passed in a http request.
Reason I'm asking is, I created a simple ASP.NET MVC application. I have two methods (shown below, example contrived for this question). one method is decorated with [HttpPost] and other one is not. when i make a call from a third party app, it hits the break point in the first function ProcessData1 and I get the id parameter as well, since it is being passed in query string.
but if i try to make a call to ProcessData2, it doesn't hit the break point in that function.
I know the third party application, I'm using is making a Http post call.
I tried another rest client and this time when I made a call to ProcessData2, it was successful.

can some one point out possible reasons?

        public ActionResult ProcessData1(string id) {          
            return View(request);

        public ActionResult ProcessData2() {          
            return View(request);
I am doing an HTTP post call to a database to pull information to load an audio player.

I am successful getting a JSON string with the desired details.

What I'm having trouble with is passing one of the JSON variables to the audio player as the source.

Here's a bit of code that shows what I'm trying to do.


<audio id="player" my-audio>
    <source src="/radio/{{dir.dv_file}}.ogg" type="audio/ogg" />
    <source src="/radio/{{dir.dv_file}}.mp3" type="audio/mpeg" />

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So what works is the <h1> tag that displays the Talent Name and the <h2>Tag that gives the total time.  I also know there is valid data for dir.dv_file but when I inspect the code, it shows it as {{dir.dv_file}}.

So what that indicates to me is that the {{dir.dv_file}} is not converted to the passed variable inside of the <audio> tag.

So my question is how do I get that variable to be passed within that <audio> tag.
Hi ,

We have enabled Mapi over HTTP and its set to true.
Internal all working but external i forgot to set the in it so i did sucsesfull.

Now i need to set per server the authentication method as its asking from outside a password to fill in.

What will be the correct command and correct or stanaard authenthication settings?
Many thanks.

It should be something like ?

Set-MapiVirtualDirectory -Identity "Servernameexchange01\mapi (Default Web Site)" -ExternalUrl -IISAuthenticationMethods Negotiate
(not sure)
Many thanks.
Hi All,

I have configured Issuing CA and Web server.

Issuing CA Roles (Certificate Authority)
Web server (Certificate Authority Web enrollment Service and OCSP)

When I try requesting a certificate directly through (http://issuingCA/certsrv) it is working fine the certificate can be issued through web console

While I try request using (https://webserver/certsrv) Everything is coming finally when i click submit on certificate request it through below error.

Error : CCertRequest::Submit: The RPC server is unavailable. 0x800706ba (WIN32: 1722

It is critical and really appreciated if any one can help this...

I'm working with an ecommerce API. Once the transaction is processed an HTTP post is sent to a URL of your choice with the transaction data (a way to confirm transaction on your site). This is fine, however how can I confirm the HTTP post is from the applicable source for security purposes? I tried $_SERVER['HTTP_REFERER'] but nothing is provided.
I would like to understand the difference of persistent connection and keep alive. Is it only applicable to HTTP protocol? Thanks!
I created an htaccess file in my directory for with the following:

order deny,allow
deny from all
allow from

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When trying to visit from my IP I get a testing 123... page if you visit link above you will see.   If I remove the .htaccess file I have full access again without any problem.  What am I doing wrong?  Do I need to use ipv6 address or something?
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I am trying to access a website through proxy server.I am using httpclient.

This is the code which is working fine:

import org.apache.commons.httpclient.Credentials;
import org.apache.commons.httpclient.HostConfiguration;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpMethod;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.UsernamePasswordCredentials;
import org.apache.commons.httpclient.auth.AuthScope;
import org.apache.commons.httpclient.methods.GetMethod;
import java.util.Properties;

public class Working {
private static  String PROXY_HOST = "";
private static  int PROXY_PORT = 80;

    public static void main(String[] args) {
    HttpClient client = new HttpClient();
    HttpMethod method = new GetMethod("");
    HostConfiguration config = client.getHostConfiguration();
    config.setProxy(PROXY_HOST, PROXY_PORT);

    try {
            if (method.getStatusCode() == HttpStatus.SC_OK) {
           String response = method.getResponseBodyAsString();
           System.out.println("Response = " + response);
    } catch (IOException e) {
    } finally {
Hi Guys,

We wrote an application that downloads json files down to about 80/90 client machines, we have reworked the mechanism but cant get it work correctly

I want to know how we could enable our server to send http status code responses then I can use the reponse.statusCode to see if a new file is available and make this whole thing a lot easier and more robust.
We just moved from WinINET to WinHTTP. The latter does not have an equivalent InternetCanonicalizeUrl function.

The WinHTTP docs say that WinHTTPOpenRequest does this automatically but there is nothing there that specifically addresses this.

According to this reference you can use WinHTTPCreateURL which uses a URL_COMPONENTS structure to define the various URL parts. In the latter the lpszExtraInfo property is where you put the ?param=xyz& ... part.

Here is my problem - one of the parameters in the paramter string needs to be canonicalized as it could contain non-URL friendly characters (Example &).

With the WinINET version we used InternetCanonicalizeUrl on the specific URL parts which were then appended to the URL string.

If we have a URL now that looks like this'Name & Surname','Description'

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And we pass that to WinHTTPOpenRequest - it does not know that the & in Name & Surname is data and not a parameter separator.

How do we canonicalize individual parameters in the URL with WinHTTP
I would like to setup redirection from a server that host a site to a different server that host a landing page in IIS.  

How do I setup a redirection in DNS and on the new site?

Hello Experts,

Somehow on some of our websites, the redirect to 443 was shut down.

How would you go about finding the missing redirects?

This is on Windows IIS.

The only thing I can think of is running scans on 80 and 443 and compare the two, but I don't think that will address the missing redirect. We do not have a Web Application Firewall to determine this.

Would the firewall reporting tools work? What the SIEM?

Thank you, your recommendations are appreciated.

We are looking for an FTP apps that we can click on a folder and get the total size of that folder, including its sub-folders; something like WinDirStat.  The most important is to get the size of the folders.  What FTP can we use?

Note: we are using FileZilla, but there is no option like what we want.

HTTP Protocol

The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems. Hypertext is structured text that uses logical links (hyperlinks) between nodes containing text. HTTP is the protocol to exchange or transfer hypertext. HTTP functions as a request-response protocol in the client-server computing model. HTTP is designed to permit intermediate network elements to improve or enable communications between clients and servers. HTTP is an application layer protocol designed within the framework of the Internet Protocol Suite; it presumes an underlying and reliable transport layer protocol.

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HTTP Protocol