What is HTTPS and Advantages of it

HTTPS – Secure HTTP

The HyperText Transport Protocol (Secure), the standard encrypted communication mechanism on the World Wide Web and this is actually just HTTP over SSL.

Advantages of HTTPS

  1. Same as HTTP, only encrypted for security purposes. HTTPS (Hypertext Transfer Protocol over Secure Socket Layer, or HTTP over SSL) is a Web protocol built into its browser that encrypts and decrypts user page requests as well as the pages that are returned by the Web server and developed by Netscape. HTTPS is really just the use of the Netscape’s Secure Socket Layer (SSL) as a sublayer under its regular HTTP application layering.
  1. The Hypertext Transport Protocol, Secure, the standard SSL communication mechanism of World Wide Web.(1) (HyperText Transport Protocol Secure) The protocol for accessing a secure Web server and using HTTPS in the URL instead of HTTP directs the message to a secure port address rather than the default Web port address of 80. The session is then managed by the security protocol.

    (2) (HyperText Transport Protocol Secure) The protocol for accessing a secure Web server and using HTTPS in the URL instead of HTTP directs the message to a secure port number rather than the default Web port number of 80. The session is then managed by a security protocol.

    (3) (HyperText Transport Protocol Server) A Web server that runs under Windows NT, developed by the European Microsoft Windows Academic Centre.

  1. HTTP layered over the SSL protocol.
  1. Secure Hypertext Transfer Protocol.
  1. Secure HyperText Transfer Protocol
  1. Same as HTTP but provides secure Internet communication using SSL.
    A type of server software which provides the ability for “secure” transactions to take place on the World Wide Web. If a Web site is running off a HTTPS server you can type in HTTPS instead of HTTP in the URL section of your browser to enter into the “secured mode”. Windows NT HTTPS and Netscape Commerce server software support this protocol. SEE ALSO: proxy server, secure server and commerce server.
  1. https is ordinary http exchanged over an SSL-encrypted session.A new implementation of the HTTP protocol that provides for more secure web communications by including encryption methods.
  2. A variant of HTTP that encrypts messages for security.(HyperText Transfer Protocol Secure) A secure protocol for sending information forth and back over the Internet and the HTTPS protocol most frequently relies on the SSL (Secure Socket Layer) encryption system but others such as TLS (Transport layer security) are also available. Every attempt has been made to provide you with the correct acronym for HTTPS and if we missed the mark, we would greatly appreciate your help by entering the correct or alternate meaning in the box below. Definitions have been compiled multiple results provided for your review and popular search engine.

Reference : Dilip Kumar Jena ( https://mstechexplore.wordpress.com )

What is HTTP

HTTP Stands for Hypertext Transfer Protocol.

It is basically used to communicate web pages to web browsers,(HTTP) is used by web servers.When your browser connects to a web server, requests a web page from the server, and downloads the page,HTTP is used. It is a common standard that enables any browser to connect to any server, anywhere in the world.

HTTP was originally designed by Tim Berners-Lee to support the special demands of web communications and with an emphasis on efficiency, and a target page load time of under a tenth of a second. Modern Internet networks can support this type of response provided the page isn’t too large and the server is too far away.

To download different parts of a web page, downloading the text, graphics, and other objects on the page in different orders,your browser can open more than one HTTP connection at once. That is why you may see the status messages in the bottom of your browser window switch between a message like “downloading 38% of 47K” to “downloading 62% of 15K” on the same page — there are different HTTP connections.

To specify the download priorities,some browsers enable you so that, for example, graphics are not loaded, text is loaded before graphics, everything is loaded at once, etc and check your individual browser preferences

Reference : Dilip Kumar Jena ( https://mstechexplore.wordpress.com )

ASP – Application Object

An application on the Web may be a group of ASP files. The ASP files work together to perform some purpose. The Application object in ASP is used to tie these files together.

The Application object is used to store and access variables from any page, just like the Session object. The difference is that ALL users share one Application object, while with Sessions there is one Session object for EACH user.

The Application object should hold information that will be used by many pages in the application (like database connection information). This means that you can access the information from any page. It also means that you can change the information in one place and the changes will automatically be reflected on all pages.

 

Store and Retrieve Application Variables

Application variables can be accessed and changed by any page in the application.

You can create Application variables in “Global.asa” like this:

<script language=”vbscript” runat=”server”>

 

Sub Application_OnStart

application(“vartime”)=””

application(“users”)=1

End Sub

 

</script>

In the example above we have created two Application variables: “vartime” and “users”.

You can access the value of an Application variable like this:

There are

<%

Response.Write(Application(“users”))

%>

active connections.

 

Loop Through the Contents Collection

The Contents collection contains all application variables. You can loop through the Contents collection, to see what’s stored in it:

<%

dim i

For Each i in Application.Contents

Response.Write(i & ”
“)

Next

%>

If you do not know the number of items in the Contents collection, you can use the Count property:

<%

dim i

dim j

j=Application.Contents.Count

For i=1 to j

Response.Write(Application.Contents(i) & ”
“)

Next

%>

 

Loop Through the StaticObjects Collection

You can loop through the StaticObjects collection, to see the values of all objects stored in the Application object:

<%

dim i

For Each i in Application.StaticObjects

Response.Write(i & ”
“)

Next

%>

 

Lock and Unlock

You can lock an application with the “Lock” method. When an application is locked, the users cannot change the Application variables (other than the one currently accessing it). You can unlock an application with the “Unlock” method. This method removes the lock from the Application variable:

<%

Application.Lock

‘do some application object operations

Application.Unlock

%>

The #include directive is used to create functions, headers, footers, or elements that will be reused on multiple pages.

 

The #include Directive

You can insert the content of one ASP file into another ASP file before the server executes it, with the #include directive. The #include directive is used to create functions, headers, footers, or elements that will be reused on multiple pages.

 

How to Use the #include Directive

Here is a file called “mypage.asp”:

<html>

<body>

<h3>Words of Wisdom:</h3>

<p><!–#include file=”wisdom.inc”–></p>

<h3>The time is:</h3>

<p><!–#include file=”time.inc”–></p>

</body>

</html>

Here is the “wisdom.inc” file:

“One should never increase, beyond what is necessary,

the number of entities required to explain anything.”

Here is the “time.inc” file:

<%

Response.Write(Time)

%>

If you look at the source code in a browser, it will look something like this:

<html>

<body>

<h3>Words of Wisdom:</h3>

<p>”One should never increase, beyond what is necessary,

the number of entities required to explain anything.”</p>

<h3>The time is:</h3>

<p>11:33:42 AM</p>

</body>

</html>

Syntax for Including Files

To include a file in an ASP page, place the #include directive inside comment tags:

<!–#include virtual=”somefilename”–>

or

<!–#include file ="somefilename“–>

The Virtual Keyword

Use the virtual keyword to indicate a path beginning with a virtual directory.

If a file named “header.inc” resides in a virtual directory named /html, the following line would insert the contents of “header.inc”:

<!– #include virtual =”/html/header.inc” –>

The File Keyword

Use the file keyword to indicate a relative path. A relative path begins with the directory that contains the including file.

If you have a file in the html directory, and the file “header.inc” resides in html\headers, the following line would insert “header.inc” in your file:

<!– #include file =”headers\header.inc” –>

Note that the path to the included file (headers\header.inc) is relative to the including file. If the file containing this #include statement is not in the html directory, the statement will not work.

You can also use the file keyword with the syntax (..\) to include a file from a higher-level directory.

 

Tips and Notes

In the sections above we have used the file extension “.inc” for included files. Notice that if a user tries to browse an INC file directly, its content will be displayed. If your included file contains confidential information or information you do not want any users to see, it is better to use an ASP extension. The source code in an ASP file will not be visible after the interpretation. An included file can also include other files, and one ASP file can include the same file more than once.

Important: Included files are processed and inserted before the scripts are executed.

The following script will not work because ASP executes the #include directive before it assigns a value to the variable:

<%

fname=”header.inc”

%>

<!–#include file=”<%=fname%>”–>

You cannot open or close a script delimiter in an INC file. This script will not work:

<%

For i = 1 To n

<!–#include file=”count.inc”–>

Next

%>

But this script will work:

<% For i = 1 to n %>

<!–#include file=”count.inc” –>

<% Next %>

The Global.asa file is an optional file that can contain declarations of objects, variables, and methods that can be accessed by every page in an ASP application.

Reference : Dilip Kumar Jena ( https://mstechexplore.wordpress.com )

ASP.NET Web Server Controls

This Post shows  How to Use Server Controls in Asp.Net Web Pages

ASP.NET Server controls
1) Html Server Controls (HtmlAnchor Control, HtmlButton Control, HtmlForm Control, HtmlImage Control…).
2) Web Sever Controls
• Basic Web Controls (Button, Checkbox, Hyperlink…).

• Validation Controls (RequiredFieldValidator Control, RangeValidator Control, CompareValidator Control..).

• List Controls (ListBox, CheckBox, RadioButtonList, Repeater, DataList, GridView, DropDownList, ListView).

• Rich Controls (AdRotator, Calender).
• User Controls.
• Custom Controls.

Table comparison is the easiest way to quickly decide which data list control is best for your specific project requirements.

Always go for the control that provides the built in feature for your needs. But In most real-life examples, you would need to write some amount of custom code to make sure that the resulting Web page shows information in the most desirable format. When choosing the control look for performance, ease of use and maintainability effects to determine the best practice.

Real time Scenarios.

Case 1: Displaying 100 records from the database using DataBind().

Comparing performance differences between the data grid, data list, and repeater controls.

Option 1 is the repeater solution, option 2 is the data list solution, and option 3 is the data grid solution.

Of the three solutions, recommended is that you consider the data list control as your first choice. Look at the data grid control only when you discover that data list doesn’t provide a desired built-in feature. Similarly, you should use the repeater only when the data list control is too slow for your needs.

Details

  1. Datagrid is most restrictive as regards to customization followed by DataList and finally Repeater is the most customizable.
  2. Datagrid has built in paging, sorting and editing capabilities which are not there with the other two controls. So if you want users to sort / page / edit data, datagrid is the natural choice.
  3. DataList and repeater have better performance than datagrid. So if performance is a major concern, for example, a site with large number of concurrent visitors, then you could think of datalist or repeater.
  4. Repeater is the most customizable. It allows you to create structures like nested lists, for example.
    A datagrid row displays one record from the data source, while a datalist row can display more than one records (set by RepeatColumns property).
  5. Datagrid and Datalist are derived from WebControl while Repeater is not, and so does not have the stylistic properties of web controls.
  6. Datalist can display more then one record in a single row. While Repeater can’t.
  7. Datalist has a property called repeat. Direction = vertical/horizontal. (This is of great help in designing layouts). This is not there in Datagrid.
    1. With same template and same data set, Repeater usually works faster of DataList or GridView controls. This is mostly because of DataReader class, which is used for read only access. DataReader is faster than DataSet or DataTable classes commonly used with GridView.
    2. DataList has RepeatDirection, RepeatColumns and RepeatLayout properties, which are unique for DataList control. These properties are useful when you need to create presentation with more than one record per row, like image gallery, product catalog etc.

10. Common problem when using GridView control could be large ViewState which makes page loads slower and requires more bandwidth. This could be insignificantly on low traffic website, but keep in mind that for each second while the page loads, the percentage of visitors will become impatient and leave website. Also, massive view state is not good for SEO (search engine optimization).

11. One more problem is using of default pager on large tables or high traffic websites. If default paging is used, GridView will load complete dataset in memory, which descreases website’s performances.

12. Since Repeater control does not generate additional HTML, it also can be used to generate RSS feeds.

Summary

Thus, we have understood the various databound controls and its advantages and disadvantages which will help us to choose the right control for our need.

To sum up,

  • Choose Gridview if your requirement is displaying tabular data. For example, a search result page where the customer expects a sorting clicking on the header. Also, it is very easy to provide custom paging with GridView when we use ObjectDataSource control.
  • Choose between DataList and Repeater control for flow/tiled layout. DataList control will help you in providing editing the data where Repeater will not.
  • If you use ASP.Net 3.5, then ListView control will satisfy almost all of your need in terms of the layout of the data display. This control is most flexible and versatile that can fit all your need.

Don’t forget to switch off the viewstate if your need is only display to get better performance.

1. If your Data access operations is mainly fetching and displaying the records and doesnt involve insert/update/delete statements and other manipulations (forward only, read only) actions, go for the DataReader.
DataReader offers a forward only read stream of access to the records. It is very useful in cases where we just grab the data from the database to display in DataGrid, Label and other Webcontrols.
However, DataReader requires the connection with the database open until its operation is completed.

2. If your Data access operations extend to as simple as an Insert/Update/Delete statement to as complex as using it as a return type from a web service, go for the DataSet. The DataSet has the following advantages.

i. Complex Data type supporting numerous methods such as ReadXML which reads new XML data to form a dataset, WriteXML which provides an XML format of the existing data, etc.,
ii. Works on the disconnected architecutre i.e. The connection doesnt need to be on for the DataSet to perform the manipulations and other actions and is required only at the time of Updating the records to the Database Table.

Reference : Dilip Kumar Jena ( https://mstechexplore.wordpress.com )