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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I would like to take a look at the actual playlist file that gets transmitted from the server to the client when the client requests an HLS video stream. According to HLS specification, the Server must transmit what's called a "playlist."

I was thinking about using WireShark networking packet analyzer to intercept this file, but I am not sure how to do it.

Any ideas?

Thank you!
We are using custom solution that is using IIS regular web server.
I have certificate configured for https://website. it is binded to 443 and working.

Users need to authenticate to the web server using windows authentication https with cert. But I am getting 401 unauthorized error for some users but not for others. In particular users in source are not able to authenticate.
Web server is in the target. But some users from source successfully authenticate. Target users have no problem to authenticate

How do you troubleshoot this issue? Where to look to solve this quickly?

We tried clearing IE cookies, moving workstations to different OUs. The issue is random. Everything worked fine few days ago, and then smth happened.

So now users are continually prompted for creds when accessing webserver url and then authentication fails with 401. Also we saw this error in the event log.

They are not suppose to get prompted at all because the web site is in the Intranet zone.

Error in the event log

failed to set DefaultTargetDNS via GetSetting http call. Error:GetConfigSetting Http call failed - url: https://website/ActivationPortal/Settings/GetConfigSetting, urlParams: configGroup=DomainSettings&keyName=defaultTargetDNS, Error: The remote server returned an error: (401) Unauthorized.,    at System.Net.HttpWebRequest.GetResponse()
   at Msm.PreMigrationTestCommon.HttpHelper.SendHttpRequest(String method, String uri, String parameters, String userName, String …
Hi all,

Can someone please assist with this? I'm new to the Sharepoint..

http://myserver/my/Person.aspx returns HTTP 404 Not Found

Thanks a lot!

I was creating some articles and upload an image for each in wordpress. From one moment to the other, failed to upload images. I've tried through the media gallery but the error is the same. The size of the images is small about 200kb and does .jpg and .png extensions.

Http Error message appears.

Image attached.

best regards
Just curious: I understand that my router does NAT between my private home network and the internet.  How can I see/follow what happens when I enter a website's url into my browser?

I've got Fiddler installed - will this show me, or do I need wireshark?
I'm trying to see things like how my Internet router tags http packets so that it know how to route return packets to my laptop's nic vs. the virtual nic in a virtual machine running on my laptop which is also using the laptop's nic to get internet access.
In summary:

When certain PC's are trying to access http (port 80) at seemingly random times, they are unable to. With sites taking a long time to load or outright failing to . It only seems to affect outgoing (through the firewall) http traffic and nothing else, eg https (port 443) still works. Internal HTTP is unaffected.
The scope of the issue is over 2 different VLANS/Subnets but does not affect all pc's on those VLANs/subnets.

The only fix is for the user to restart the local PC at this time.  

Checked locally on the machines affected with all sorts of various attempts to fix.
Restarted any and all networking gear.
Ran wireshark packet traces.

Although we have performed WS traces we don't currently have the experience to identify issues, therefore any pointers would be greatly appreciated.
On a webpage "" that I access frequently, when I click on any of the hyperlinks the "http://" is removed from the url in the address and then the resulting page is just blank. If I add the "http://" back in, I get the expected page in its entirety. This was working just fine yesterday. Any ideas why this would be happening?
I contacted the website owner and they tell me they are having no problem accessing the pages

I refer to the above link (EE article# 36120990 & 36129509) .

I need a similar Windows script to test all the IP addresses in our corporate for Canon, HP & Ricoh printers.

So if I manually issue from my PC's command prompt below:
c:\> telnet 10.x.y.z 80

GET /index.htm / HTTP/1.1 <hit_ENTER>

HTTP/1.1 400 Bad Request
Date: Thu, 07 Jul 2016 10:35:10 GMT
Server: CANON HTTP Server  <== this tells me it's CANON
Content-Type: text/html
Content-Length: 109

<BODY><H1>400 Bad Request
Your browser sent a request that this server could not understand.</BODY>
Connection to host lost.

However, I simply just did not manage to capture the above output despite trying:
  start telnet 10.x.y.z 80 < input.txt > tel.out 2> tel.err   (this command is no good as the spawned windows just hang there)
  cmd telnet 10.x.y.z 80 < input.txt > tel.out 2> tel.err

where input.txt contains:
GET /index.htm / HTTP/1.1
(with 2 empty lines that follow)

type tel.out gives:
Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

type tel.err gives:
'GET' is not recognized as an internal or external command,
operable program or batch file.

What did I miss?   What I need is an output file that captures the "Server: CANON ..." line
& I'll be …

I need a little help with some DNS please.

We have an test website ( which is only accessed internally.  In DNS we have a HOST (A) record for testwebsite1 to point to the IP address of the server.

I have had a request to point a second domain name ( to the same server.

I believe that best practise in this scenario is to use an Alias (CNAME), to point to so this is what I have done.

However, when I use my browser to go to I just get an HTTP 404 not found page.

If I do an "nslookup" it tells me that it is correctly pointing to so I am not sure why the page is not loading.

Can you help please?

I have been getting a lot of emails following the pattern below. I wonder if anyone can
1) Figure out what information might be captured by the __VIEWSTATE / __VIEWSTATEGENERATOR gambit
2) Decode the strings passed to __VIEWSTATEGENERATOR and __VIEWSTATE (What is the process? I can write Java code for this if I need to)
3) Comment on the vulnerability of my Windows 7 machine to this approach. It seems that any online security discussions about VIEWSTATE start with the assumption that the server needs to be protected. However unless I am mistaken, this turns it around and threatens to compromise the user machine. Am I correct in thinking that this is likely a preliminary step towards a later infection attempt? Your comments are appreciated!

I know next to nothing about asp, though I have an extensive background in software generally.


Email subject : "Cooperation with a large firm" Received 2016-06-12

We are looking for employees working remotely.

My name is Dominick, am the personnel manager of a large International company.
Most of the work you can do from home, that is, at a distance.
Salary is $2500-$5000.

If you are interested in this offer, please visit Our Site<--A LINK

****************** This is the link given in the initial email
When I open my WCF service locally on the server using http://localhost/AppName/MyService.svc?wsdl it works fine, but when i access it remotely using http://ServerName/AppName/MyService.svc?wsdl it does not work. What am I missing?

Please if anyone knows of this issue: how Use  URLDownloadToFile to download snapshot from ipcam using http://ipcam:port/snapshot.cgi? instead http://ipcam:port/snapshot.jpg? can i use or any other function or libraie?

I explain:

I have a surveillance program in Excel 2000 vbasic. I using a intellinet  camera, I can download  a spanshot from a url and namefile.jpg  Using the following code:

Declare Function Beep Lib "kernel32" (ByVal dwFreq As Long, ByVal dwDuration As Long) As Long
Private Declare Function URLDownloadToFile Lib "urlmon" Alias "URLDownloadToFileA" _
     (PCaller ByVal As Long, ByVal szURL As String, ByVal szFileName As String, ByVal dwReserved As Long, _
  LpfnCB ByVal As Long) As Long

Private Declare Function DeleteUrlCacheEntry Lib "WinINet.dll" _
    Alias "DeleteUrlCacheEntryA" _
   (LpszUrlName ByVal As String) As Long

nfile= “mm-dd-aa_hh-mm-ss.jpg”
image = 
URLDownloadToFile RetVal = (0, image, pathrep & nfile, 0, 0)
Call DeleteUrlCacheEntry (image)

In the intellinet cam, snapshot was fixed in the filename image.jpg and locatable on the path shown. The last line (call delete…) erased the image cache so that it does not "freeze" snapshot at a particular time.

New other cams usin severals ways, for example:

The  foscam f9821w v2  use:
but not work with…
I have 2 domain names: and I have hosted on Mac OS X 10.10.5 using Server version 5.0.15. I have A records setup in DNS so that both domain names ( and point to the same IP address for the OS X Server machine.

We have a wildcard SSL cert of * installed on the OS X Server machine. I have a redirect configured in OS X Server (I believe this uses Apache) so all traffic for the http version of is going to the https version of This is working properly.

The problem is if anyone uses http version of They get a warning that the connection is not secure because their browser is trying to redirect to https version of We do not have an SSL cert for

Is there a way to setup a redirect so that any traffic coming from http://users.* (newsite or oldsite) gets redirected to https version of

I can enter a URL matching a regular expression and direct that in the Server app, but I don't know what to enter to get the redirect to work properly so that the http versions of AND both redirect to the https version of

I have attached a screen shot of the redirect I have setup for http to https.  I only have one site hosted on this OS X Server machine.

I had this question after viewing problems installing a ssl certificate on a mac that is a local machine with no domain.

very simply how do i generate a csr that contains my organization name to send to verisign or whoever and get an intermediate ca from them?  right now when i do it, i get an error because the organization name is empty.  dont see even remotely where to put this in.  dont want a self signed certificate and dont have the osx server app installed.  there has got to be a way to generate this csr so that it actually works

os x is yosemite
All of our network traffic is routed through a proxy server, including https traffic. We have a digitally signed security certificate which enables routing https traffic too.
We're looking for a solution where if the security certificate is untrusted by the browser (i.e. our security certificate hasn't been installed yet) prompt the user to download our security certificate.
I am posting the result when I was testing active sync. through test exchange

how can I solve the problem.
The Microsoft Connectivity Analyzer is testing Exchange ActiveSync.
Testing HTTP Authentication Methods for URL
The HTTP authentication test failed.

we have existing url which is working fine
we developed new squid 3.3 and are trying to use for active sync which is failing.
Additional Details
A Web exception occurred because an HTTP 503 - ServiceUnavailable response was received from Unknown. HTTP Response Headers: Mime-Version: 1.0 X-Squid-Error: ERR_SECURE_CONNECT_FAIL 71 Vary: Accept-Language Content-Language: en X-Cache: MISS from X-Cache-Lookup: MISS from Connection: keep-alive Content-Length: 3860 Content-Type: text/html Date: Fri, 20 May 2016 11:16:17 GMT Server: squid
Elapsed Time: 307 ms.

I am getting below error on squid proxy logs

In the cache.log “fwdNegotiateSSL: Error negotiate SSL connection on FD 14: error:14090086:SSL routine:SSL3 routines: SSL3_GET_SERVER_CERTIFICATE: certificate verify (1/-1/0)”
I want to use an encrypted string in an email as a type of token for a reset, so I generate the string as:-

It arrives in my inbox fine, and shows the as:-

When I click on the link, again works fine:-
The first code block returns a good request.  The second returns a fault.  Please advise.
  using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Net;
    using System.ServiceModel;
    using System.ServiceModel.Channels;
    using System.Text;
    using System.Threading.Tasks;

    namespace Ahcccs.Isd.Aes.Breaz.Core.WCF.SOAP
        public class ConsumeGetVendorLookup
            public void Consume(string wso2token)
                Header header = new Header();
                header.Type = "?";
                header.ReturnCode = "?";
                header.Requestor = "?";
                header.Recipient = "?";
                header.Date = "?";
                Requestor requestor = new Requestor();
                requestor.UserID = "";
                requestor.Password = "";

                header.Subject = requestor;

                Payload payload = new Payload();
                GetVendorCustomerIn getVendorCustomer = new GetVendorCustomerIn();
                getVendorCustomer.IncludeGeneralInfo = true;
                getVendorCustomer.IncludeHeadquarters = true;
                getVendorCustomer.IncludePrenote_EFT = true;
                getVendorCustomer.IncludePrenote_EFTSpecified = true;
                getVendorCustomer.Vendor_Customer = "{our customer number}";

                payload.GetVendorCustomerIn = getVendorCustomer;

                AdvMessage advMessage = new 

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I have a field that I am displaying in my ASP which contains ASP code (nvarchar field).
The problem I have is that it is displaying the HTML code, instead of the text within the HTML code.

here is what I get

&nbsp;USCIS has published an updated <a href="">Welcome to the United States: A Guide for New Immigrants</a>. The guide contains practical information to help new immigrants settle into everyday life in the United States, including how to find a place to live, how to get a Social Security number and how the U.S. system of government works. | &nbsp;Beginning with the November 2015 Department of State (DOS) Visa Bulletin, if USCIS determines that there are more immigrant visas available for a fiscal year than there are known applicants for such visas, we will state on <a href=""></a> that applicants may use the <em>Dates for Filing Visa Applications</em> chart. Unless otherwise stated on our website, the <em>Application Final Action Date</em> chart will be used to determine when individuals may file their adjustment of status applications. | 

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I display it as:  

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Being an "Assembly Language Developer from way back",  I am used to looking at a program and following the code sequentially: You execute Line 1, then line 2, etc (unless of course something like an IF statement redirects that flow)
NOW I am having trouble understanding how to follow the flow of execution in an HTML Page that has a lot of snipets of PHP code in it.
SO as a human trying to follow along to see what the code is doing, here's my questions:
1.  I hear that a Script can go anywhere in a web page. I presume that is true for PHP in an HTML page also. So if I am following along the flow of execution, do I "ignore" anything in between the <?php and the ?> tags ... until another part of the code "calls" that section, like a subroutine?
2. Or do those sets of PHP code get executes first, immediately?
3. Or ?? I am asking specifically about PHP, but also wondering if all scripting languages handle this contol flow the same way in an HTML page (Javascript, VB Script?)
Thanks for any help wrapping my brain around this!
- B
Hi All,
A company we use to host our websites recently retired some old servers, which in turn force me to change to new name server in my Go Daddy account. No big deal I have done this before.
Website in question is a public website, no logging in etc... From outside our network the website in question is totally accessible with no issues. Type into your browser, and away it goes, can ping the website as well no problem,
Inside my network is a different story: I can ping the website in question by DNS name with no problem, but if I go to the website and I get the 403 forbidden.
I have in house Server 2012 R2 that doubles as DC, and DNS server. I have always in my DNS had the website in question set with a static IP, because the website and my local domain are the same except the external is .com and internal is .local
I am not the greatest by any means no a lot about DNS, but I just opened DNS from the Server Manager, and found every instance I could that had the .com website address, and I modified the IP address with with the new IP address.
And now I get the 403 Forbidden when any PC inside my network tries to access the .com website.
I went back to double check my work, and I noticed that I think the Fully Qualified Domain Name for this website had changed to the 3 instances, Others ones had combination of and website.local as the FQDN. All other websites come up fine.
Any help would…
I need to setup a URL redirection for my website.  I need to redirect* to*.  I am using Joomla 2.5 and downloaded the ReDj extension but I am getting an error on the install.  Looking for a good solution.

Thanks, Jon
Not being a web person, i have to ask this seemingly easy question.  Random guides found on a google search are complicated because we already have a url-rewrite in place

we want to make it so anyone who goes to our site at by http, are on-the-fly and blindly redirected to while maintaining our existing url-rewrite

Our existing rewrites are handled by web.config it the root of the site and is in the code block below.

<?xml version="1.0" encoding="UTF-8"?>
                <clear />
                <rule name="Rewrite rule1 for CRMsoftwareTest" enabled="true" stopProcessing="true">
                    <match url="(CRMsoftware|api)(.*)" negate="true" />
                    <conditions logicalGrouping="MatchAll" trackAllCaptures="false" />
                    <action type="Redirect" url="CRMsoftware/portals{REQUEST_URI}" appendQueryString="false" redirectType="Found" />
                <rewriteMap name="CRMsoftwareTest" />

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I setup https on tomcat 7 by editing my server.xml and web.xml
Some of the webapps are not working, and I need to revert to http to test.
I removed the changes I made to server.xml and web.xml, and restarted tomcat,
it keeps resolving the address to https, and keeps stating page can not be displayed.
Here is my current server.xml

  Licensed to the Apache Software Foundation (ASF) under one or more
  contributor license agreements.  See the NOTICE file distributed with
  this work for additional information regarding copyright ownership.
  The ASF licenses this file to You under the Apache License, Version 2.0
  (the "License"); you may not use this file except in compliance with
  the License.  You may obtain a copy of the License at

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  See the License for the specific language governing permissions and
  limitations under the License.
<!-- Note:  A "Server" is not itself a "Container", so you may not
     define subcomponents such as "Valves" at this level.
     Documentation at /docs/config/server.html
<Server port="8005" shutdown="SHUTDOWN">
      <!-- Security listener. Documentation at /docs/config/listeners.html
  <Listener …
I have Python 2.7.9 running on a linux box. Now I need to sending http post request with body and headers. However, due to some restrictions, I cannot use pip to install some third party modules, and I cannot use Python to execute "curl" command either. Can I achieve this with Python out of the box?

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