How to Use the ListBox Control in ASP.NET 2.0

Any developer who is using the Listbox control in his applications needs to be aware of how data binding has changed from VS 2003 to ADO.NET 2.0. This article will explain the changes. It appears to be an improvement over the previous techniques used.Introduction

While the concept of data binding has not changed, the mechanics and objects involved in data binding have changed from VS2003 (.NET Framework 1.1x) to ADO.NET 2.0. This can be easily seen by comparing the Toolbox items in VS2003 and VS2005 as shown in the next two pictures. The connection, command, transactions, parameters have been replaced by the DataSource Controls. The data binding in ASP.NET 2.0 relies on the data binding expressions and the data source controls. This tutorial is about the ListBox control and how it is bound to data. It should interest those who might be using ListBox Control in their applications. You will see for yourselves how much better off you will be using the Data Source Controls in ADO.NET 2.0.

VS 2003

VS 2005

ListBox Control

The ListBox control displays items in a list appearing sequentially and vertically in a scrollable window. It may display single or multiple items. It usually displays items by pulling the information from memory and formatting them according to the way they are requested. The ListBox control as seen in the Object Browser of VS 2005 has its inheritance as shown in the next paragraph.

Public Class ListBox Inherits System.Web.UI.WebControls.ListControl Member of: System.Web.UI.WebControls Summary: Represents a list box control that allows single or multiple item selection.

This inheritance is common to the other type of list controls as well, such as DropDownList, CheckBoxList, RadioButtonList and the BulletItemList which is new in VS 2005.

Because of this inheritance one can access a large number of properties, methods and events of the list controls in applications shown in the Object Browser.

The ListBox control has additional properties for setting its BorderColor, BorderStyle, and BorderWidth. Also it has some properties not available in other types of list controls, namely Rows and SelectionMode properties shown in the object browser.

In an earlier article on VS2003 an example of binding a ListBox control using a DataReader was shown. ListBox can be used to display not only data from a backend database but also other kinds of lists. ListBox events can then be used for displaying list-related information. The following examples use either simple lists or data from a backend database. In the case of a backend database, however, any of the data source controls can be used. For the examples shown an AccessDataSource Control in the VS 2005 IDE is chosen.

On Using the AccessDataSource Control

The AccessDataSource control takes you the very center of RAD. Writing code is almost reduced to a single line. No more connection strings that tangle here, there and everywhere. Most of what you want to do can be done at design time. The IDE even gives you a query editor. An earlier article shows how you may use this data source control with a large number of screen shots. A few major screen shots are shown here.

Step 1

You must first add a source to the data connection, which will add the nwind.mdb file on your local drive as shown in the Server Explorer window. In this picture it is shown as being refreshed.

Step 2

Next you bring the connection to the App_Data folder of your website. When this is accomplished your website should appear as shown in the following picture.

Simple List

This example shows filling a ListBox with several items at design time. The next picture shows the ListBox on the design pane filled in with three items. The List Items Collection Editor dialog can be popped up by clicking on an empty space in the items collection property in the List Box properties window shown in the same picture on its right. In this Editor you can begin adding items by providing Key/ Value pairs as shown for “New Jersey.”

Another way of doing this is to follow the ListBox tasks as shown in the next picture by clicking the smart tags arrow attached to the ListBox. This will be discussed later in the tutorial.

By using the SelectedIndexChanged event you may be able to write a code so that the Key Value of selected items is displayed in the textbox as shown in the following snippet.

Partial Class Simplelist
Inherits System.Web.UI.Page

Protected Sub ListBox1_SelectedIndexChanged(ByVal sender _
As Object, ByVal e As System.EventArgs) Handles _
ListBox1.SelectedIndexChanged
TextBox1.Text = ListBox1.SelectedValue.ToString
End Sub
End Class

The source code for this program (SimpleList.aspx) is shown in the following listing.

<%@ Page Language=”VB” AutoEventWireup=”false”
CodeFile=”Simplelist.aspx.vb” Inherits=”Simplelist” %>

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN”
“http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>

<html xmlns=”http://www.w3.org/1999/xhtml” >
<head runat=”server“>
<title>Simple List</title>
</head>
<body>
<form id=”form1″ runat=”server”>
<div>
<asp:ListBox ID=”ListBox1″ runat=”server”
AutoPostBack=”true” >
<asp:ListItem Value=”NJ”>New Jersey</asp:ListItem>
<asp:ListItem Value=”C0″>Colorado</asp:ListItem>
<asp:ListItem Value=”NY”>New York</asp:ListItem>
</asp:ListBox>
<asp:TextBox ID=”TextBox1″ runat=”server” Text=”>
</asp:TextBox></div>
</form>
</body>
</html>

The result of opening this page in the browser and selecting any of the list items will display its key value in the textbox as shown in the next picture.

The selected item is bound to a textbox with a Binding expression.

This example is similar to the previous one, but the Selected Item’s value is bound to the textbox with a binding expression as shown in the code used for the “text” property of the textbox. Adding items to the ListBox is similar to the previous example. The ListBox and the textbox are tied up in the form1_load() event as shown in the following snippet for the code behind for this page, BindingExp.aspx.

Partial Class BindingExp Inherits System.Web.UI.Page Protected Sub form1_Load(ByVal sender As Object, _ ByVal e As System.EventArgs) Handles form1.Load DataBind() End Sub End Class

The source code for this page (BindingExp.aspx) is shown in the following listing.

<%@ Page Language=”VB” AutoEventWireup=”false” CodeFile=”BindingExp.aspx.vb” Inherits=”BindingExp” %>

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN”
“http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>

<html xmlns=”http://www.w3.org/1999/xhtml” >
<head runat=”server”>
<title>Bound List</title>
</head>
<body>
<form id=”form1″ runat=”server”>
<div>
<asp:ListBox ID=”ListBox1″ runat=”server”
AutoPostBack=”true”>
<asp:ListItem Value=”57″>John</asp:ListItem>
<asp:ListItem Value=”35″>Tom </asp:ListItem>
<asp:ListItem Value=”22″>Lisa</asp:ListItem>
</asp:ListBox>
<asp:TextBox ID=”TextBox1″ runat=”server” Text=”<%#
ListBox1.SelectedValue %>”>
</asp:TextBox></div>
</form>
</body>
</html>

here are two ways you can populate the list with backend data. Well, not exactly two ways so much as two procedures using the same AccessDataSource Control.

Example 1: The Long hand

The first of these is a roundabout way of getting the result. It still uses the AccessDataSource control by starting off using its connectionString as shown in the following (litany?) snippet. This was how data was accessed using ADO.NET 1.0.

Imports System.Data.OleDb
Partial Class _Default
Inherits System.Web.UI.Page

Protected Sub Button1_Click(ByVal sender As Object, _
ByVal e As System.EventArgs) Handles Button1.Click
Dim ds As New AccessDataSource
ds = AccessDataSource1
Response.Write(ds.ConnectionString)
Dim mycon As New OleDbConnection
Dim conStr As String = ds.ConnectionString
mycon.ConnectionString = conStr
mycon.Open()
Response.Write(“<h2>” & mycon.State & “</h2>”)
Dim myCmd As New OleDbCommand
myCmd.Connection = mycon
myCmd.CommandType = Data.CommandType.Text
myCmd.CommandText = ds.SelectCommand.ToString
Try
Dim dr As OleDbDataReader = myCmd.ExecuteReader
Response.Write(dr.HasRows)
‘Dim str As String = “”
While dr.Read
ListBox1.Items.Add(dr.Item(“CustomerID”) & _
“,” & dr.Item(“CompanyName”) & “,” & _
dr.Item(“LastName”) & “,” & _
dr.Item(“City”) & “,” _
& dr.Item(“HomePhone”))
‘Response.Write(str)
End While
dr.Close()
Catch ex As System.Data.OleDb.OleDbException
Response.Write(ex.Message)
End Try

mycon.Close()

End Sub
End Class

You may recall that this code is similar to what was formerly used in the VS2003 and described in a previously referenced article. The Design pane of this page (Default.aspx) is shown in the next picture followed by the source code listing of the page. In the source code make sure that the SelectCommand is all in one line. It should work as is except that the VS2005 IDE editor may emit some errors (it will work in spite of the emitted HTML error).

<%@ Page Language=”VB” AutoEventWireup=”false” CodeFile=”Default.aspx.vb” Inherits=”_Default” %>

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN”
“http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>

<html xmlns=”http://www.w3.org/1999/xhtml” >
<head runat=”server“>
<title>Longwinded</title>
</head>
<body>
<form id=”form1″ runat=”server”>
<div id=”DIV1″ runat=”server”>
<asp:ListBox ID=”ListBox1″ runat=”server”
AppendDataBoundItems=”True” AutoPostBack=”false”
Height=”172px” Width=”650px” >

</asp:ListBox><asp:AccessDataSource
ID=”AccessDataSource1″ runat=”server”
DataFile=”~/App_Data/nwind.mdb”
SelectCommand=“SELECT Customers.CustomerID,
Customers.CompanyName, Customers.ContactName,
Employees.LastName, Employees.City, Employees.HomePhone,
Orders.OrderDate
FROM ((Customers INNER JOIN Orders ON
Customers.CustomerID = Orders.CustomerID)
INNER JOIN Employees ON
Orders.EmployeeID = Employees.EmployeeID)
WHERE (Orders.OrderDate > #5/1/1998#)”>
</asp:AccessDataSource>
<asp:Button ID=”Button1″ runat=”server”
Text=”Button” /></div>
</form>
</body>
</html>

Example 2: Using DataSource directly

The code behind shown for this CodeBound.aspx is simple and effortless thanks to the ADO.NET 2.0 DataSource controls. Some of the AccessDataSource controls’ properties are used. The source code listing is also simpler as shown. The design pane of this example is exactly the same as in the previous example (Default.aspx). For this example you add the ListBox to the design pane and attach the datasource; you can get drop-down hints for writing the code.

First, the code behind the click event of the button.

Imports System.Data.OleDb
Partial Class CodeBound
Inherits System.Web.UI.Page

Protected Sub Button1_Click(ByVal sender As Object, _
ByVal e As System.EventArgs) Handles Button1.Click
Dim ds As New AccessDataSource
ds = AccessDataSource1
Dim sqlstr As String = “Select * from Customers”
ds.SelectCommand = sqlstr

ListBox1.DataSource = ds
ListBox1.DataValueField = “CustomerID”
ListBox1.DataTextField = “CompanyName”
ListBox1.DataBind()
End Sub
End Class

The source code listing of CodeBound.aspx is much simpler than the previous case as shown below. Less code is the key word here.

<%@ Page Language=”VB” AutoEventWireup=”false”
CodeFile=”CodeBound.aspx.vb” Inherits=”CodeBound” %>

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN”
“http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>

<html xmlns=”http://www.w3.org/1999/xhtml” >
<head runat=”server”>
<title>Code Bound</title>
</head>
<body>
<form id=”form1″ runat=”server”>
<div>
<asp:ListBox ID=”ListBox1″ runat=”server” Height=”177px”
Width=”333px”>
</asp:ListBox><asp:AccessDataSource
ID=”AccessDataSource1″ runat=”server”
DataFile=”~/App_Data/nwind.mdb”
SelectCommand=”SELECT [CustomerID], [CompanyName],
[City], [Phone] FROM [Customers]“>
</asp:AccessDataSource>
<br />
<br />
<asp:Button ID=”Button1″ runat=”server”
Text=”Button” /></div>
</form>
</body>
</html>

This page gets rendered as shown in the next picture when the button is clicked.

n the previous two examples the ListBox was not bound to data at design time (see the design pane). In the following example the ListBox is bound to the DataSource as seen in the design view of this page, BoundList.aspx.

The source code for this page is as shown here.

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN”
“http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>

<html xmlns=”http://www.w3.org/1999/xhtml” >
<head runat=”server“>
<title>Databound Expression</title>
</head>
<body>
<form id=”form1″ runat=”server”>
<div>
<asp:ListBox ID=”ListBox1″ runat=”server”
DataSourceID=”AccessDataSource1″
DataTextField=”ContactName”
DataValueField=”City”
AutoPostBack=”True” >

</asp:ListBox><asp:AccessDataSource ID=”AccessDataSource1″
runat=”server” DataFile=”~/App_Data/nwind.mdb”
SelectCommand=”SELECT [CustomerID], [CompanyName],
[ContactName],
[Address], [City], [Phone] FROM [Customers]” >
</asp:AccessDataSource>

</div>
<asp:TextBox ID=”TextBox1″ runat=”server”></asp:TextBox>
</form>
</body>
</html>

There is no code behind to populate the list. The list is bound to data at design time. This is indeed an excellent enhancement for those who do not want to use the code but who are adept at designing using the IDE. There is some code behind but that is only for displaying a selected value in a textbox as show here.

Partial Class BoundList
Inherits System.Web.UI.Page

Protected Sub ListBox1_SelectedIndexChanged(ByVal sender _
As Object, ByVal e As System.EventArgs) Handles _
ListBox1.SelectedIndexChanged
TextBox1.Text = ListBox1.SelectedValue
End Sub
End Class

The following picture shows how this page gets rendered when the button is clicked. Note that the ListBox’s Selected value really references the DataFieldValue in the source code.

The starting point is to drop a ListBox control on the design pane. Then click the smart tag arrow attached to the ListBox at top right to open the tasks window as shown.

Now click the Choose Data Source… hyperlink to open the next page of the wizard.

In this wizard use the drop-down to choose AccessDataSource1. This may open up other drop-downs. Since you are not sure of the item and the dropdown does not show any items, just click OK.

This modifies the task list to add a new item, Configure Data Source… as shown.

Click on Configure Data Source settings, which opens up the next screen. This screen comes up with the datasource you have already configured as shown in the next picture.

Click on the Next button to reveal the next screen, Configure the Select Statement. Here you can do a lot of filtering and sorting of data using all the clauses of the SQL SELECT statement. For this example only the “City” column is chosen.

A click on the next button takes you to the following screen, Test Query, where you can test the query as shown using the Test Query button.

When you click the Finish button you get bound to data as shown in the next picture. You may also enable AutoPostBack.

Summary

This tutorial described the various ways a ListBox server control in ASPNET 2.0 gets populated with either hard coded data or data from a backend database. An MS Access 2003 database was used. The ADO.NET 2.0 Data Source Controls makes the coding much easier. The GUI provides all the necessary items for fashioning appropriate queries.

Source :http://www.aspfree.com/c/a/ASP.NET-Code Date :23-10-2008

Mengenal Gaza

Jalur Gaza atau sering disebut dengan Gaza adalah nama wilayah yang terletak di Timur Tengah, tepatnya di Palestina, sebelah barat daya Palestina ’48 (wilayah Palestina sebelum perang tahun 1948). Sebelah selatan berbatasan dengan Mesir, sebelah barat, timur dan utara berbatasan dengan wilayah Palestina ’48.

Gaza merupakan wilayah yang bentuknya memanjang dan sempit. Panjang wilayahnya 45 km, lebar 5,7 km di beberapa bagian dan 12 km di bagian yang lain yaitu berbatasan dengan Mesir. Sehingga jika dijumlah, luas Jalur Gaza adalah 365 km persegi.

Bagi Kaum muslimin, Gaza merupakan negeri yang bersejarah, negeri perjuangan dan negeri syuhada’, karena banyaknya rakyat Gaza yang syahid di jalan Allah, mulai dari bayi, anak-anak, remaja, hingga nenek-nenek dan kakek-kakek yang dibunuh tentara Zionis Iarael.

Gaza akan selalu diingat dan dikenang khususnya bagi mereka yang mencintai keluarga Rasulullah saw, bagi mereka yang menjadi pengikut mazhab Imam Syafi’i, bagi mereka yang berjuang dan melanjutkan perjuangan Imam Hasan Al Banna dengan gerakannya yang terkenal, Al Ikhwan Al Muslimin.

Datuk Rasulullah saw, Muhammad bin Abdillah, wafat dan dikubur di Gaza. Datuk Rasulullah saw namanya adalah Hasyim bin Abdu Manaf. Beliau adalah orang tua dari kakek Rasulullah saw, Abdul Muththalib yang terkenal dengan sebutan Syaibah karena ada segumpal rambut putih di kepalanya.

Imam Syafi’i, murid Imam Malik, pendiri mazhab Syafi’i, lahir pada bulan Rajab tahun 150 H (767 M) di Gaza, hari kelahiran Imam Syafi’i bertepatan dengan hari wafatnya Imam Abu Hanifah di Baghdad dan wafatnya Imam Ibnu Juraij Al Makky, seorang alim besar di kota Makkah, dikenal dengan Imam Ahli Hijaz.

Imam Syafi’i, nama lengkapnya Muhammad bin Idris bin Abbas bin Utsman bin Syafi’i bin Saib bin Ubaid bin Abu Yazid bin Hasyim bin Abdul Muththalib bin Abdu Manaf bin Qushaiy. Silsilah dari jalur ibunya, Fathimah binti Abdullah bin Al Hasan bin Husain bin Ali bin Abi Thalib (paman Nabi saw).

Bagi umat Islam yang mengikuti mazhab imam Syafi’i seharusnya memiliki kepedulian yang tinggi terhadap Gaza, kota kelahiran Iman Syafi’i, yang saat ini penduduknya sedang disiksa secara masal oleh Zionis Israel dengan cara blokade.

Akibat blokade yang diterapkan penjajah Zionis Israel terhadap rakyat Gaza, maka kebutuhan pokok berupa makanan, susu untuk bayi, obat-obatan dan BBM (Bahan Bakar Minyak) tidak dapat masuk Gaza.

Berbagai obat-obatan yang dibutuhkan rakyat sudah menipis dan sebagian sudah habis. Jenis obat yang habis tersebut diperkirakan berjumlah 160 jenis. Sekitar 90 alat kedokteran sudah tidak dapat dipakai lagi karena tidak ada suku cadang yang dapat digunakan untuk memperbaikinya

Apabila “kejahatan kemanusiaan” ini dibiarkan terus, tanpa ada yang mau dan mampu mencegahnya, maka tidak menutup kemungkinan akan terjadi tragedi kemanusian di abad modern.

Gaza adalah tempat yang pernah dikunjungi oleh Mursyid ‘Am Al Ikhwan Al Muslimin, Imam Hasan Al Banna, didampingi Ustadz. Abdah Qasim, Sa’duddin Al Walili dan Syekh Muhammad Farghali, Jum’at, 1948.

Imam Hasan Al Banna datang langsung ke kota Gaza, Palestina ditengah kesibukannya dalam berdakwah, untuk memberikan semangat kepada pasukan Al Ikhwan Al Muslimin yang berjihad di Palestina dan memberikan dukungan serta bantuan nyata kepada rakyat Palestina yang sedang berjuang melawan penjajah.

Ketika berada di kantor cabang Ikhwan, di kota Gaza Hasyim, Palestina, Imam Hasan Al Banna menulis kalimat singkat dibuku tamu yang tersedia. Kalimat tersebut tertulis dengan jelas: Hari ini, aku mengunjungi Kantor Cabang Ikhwan di kota Gaza Hasyim. Aku mempertanyakan asal-usul nama ini, Gaza Hasyim. Seseorang berkata kepadaku bahwa Hasyim adalah kakek Rasulullah saw yang kuburannya terdapat di kota Gaza.

Sekarang di Gaza, Palestina, negeri tempat dikuburnya datuk Rasulullah saw, Hasyim bin Abdu Manaf, tempat lahirnya Imam Syafi’i, tempat yang pernah dikunjungi Imam Hasan Al Banna, penduduknya sedang menderita, gelap gulita setiap hari karena pasokan BBM untuk listrik dihentikan Zionis Israel, anak-anak hidupnya tercekam, ketakutan, kebutuhan pokok makin menipis, makanan sulit didapat, penderitaan tersebut akibat blokade yang dilakukan penjajah Zionis Israel.

Disamping itu, dengan adanya tembok pemisah yang tingginya 8 m dan dalamnya 6 m dari permukaan tanah, tembok pemisah dikenal dengan nama “tembok rasialis” atau “tembok apharteid”, praktis penjajah Zionis Israel telah memenjarakan dan mengurung penduduk Gaza yang berjumlah sekitar 1,5 juta orang di kawasan yang luasnya 365 km persegi.

Sungguh sangat menyedihkan, sangat memilukan, betapa tidak? Umat Islam yang berjumlah sekitar 1,3 milyar tidak mampu menghentikan kebiadaban dan kezaliman yang dilakukan penjajah Zionis Israel di Gaza, Palestina.

Kezaliman yang dilakukan penjajah zionis Israel sampai kini masih terus berlanjut, bahkan mereka juga melakukan politik adu domba, politik devide et impera diantara rakyat Palestina.

إِنَّمَا الْمُؤْمِنُونَ إِخْوَةٌ فَأَصْلِحُوا بَيْنَ أَخَوَيْكُمْ وَاتَّقُوا اللَّهَ لَعَلَّكُمْ تُرْحَمُونَ ﴿١٠﴾

Sesungguhnya orang-orang mukmin adalah bersaudara karena itu damaikanlah antara kedua saudaramu dan bertakwalah kepada Allah supaya kamu mendapat rahmat. (QS:Al Hujuraat: 49 :10).

Apakah kita membiarkan saja rakyat Palestina ditindas, dijajah, dizalimi Zionis Israel? Lantas dimana ukhuwah kita? Dimana solidaritas kita? Dimana keimanan kita?

Rasulullah saw pernah bersabda:

Tidak beriman seseorang dari kamu sehingga ia mencintai saudaranya seperti ia mencintai dirinya sendiri. (HR. Bukhari dan Muslim dari Anas ra).

Barangsiapa menghilangkan kesusahan seorang muslim, niscaya Allah akan menghilangkan satu kesusahan di hari kiamat. Barangsiapa menutup aib seorang muslim, niscaya Allah akan menutup aibnya di hari kiamat. Allah selalu menolong hamba selama dia menolong saudaranya. (HR. Muslim).

Sekarang, marilah kita buat sejarah yang baik, sejarah yang akan bermanfaat untuk kita dan anak cucu dikemudian hari, sejarah yang dapat menghibur dan menyenangkan hati saudara-saudara kita di Gaza khususnya dan Palestina umumnya.

Caranya? Bantu mereka dengan doa! Dengan dana! Dengan tulisan dan lisan! Tunjukkan rasa empati dan peduli terhadap perjuangannya! Jangan membeli makanan dan minuman serta produk lainnya yang keuntungannya diberikan untuk Zionis Israel.

Jika tidak mau membantu, jangan buat mereka sakit hati dengan prilaku borju, hedonis, materialis yang dipertontonkan secara vulgar tanpa ada perasaan malu.

H. Ferry Nur S.Si

Email : ferryn2006@yahoo.co.id
Website : www.kispa.org

Salurkan Infaq Peduli Al Aqsha

Ke Bank Muamalat Indonesia (BMI) Cabang Slipi

No. Rek. 311.01856.22 an Nurdin QQ KISPA

A Must Read . . . . Difference between…

Difference Between Image and Picture

IMAGE – An image of your self or anyone (Usually taken through Camera)

PICTURE - A Picture is to draw something in the computer/real life.

Difference Between 1G, 2G, 2.5G, 3G, Pre-4G and 4G

1G is the first generation celullar network that existed in 1980s. It transfer data (only voice) in analog wave, it has limitation because there are no encryption, the sound quality is poor and the speed of transfer is only at 9.6kbps.

2G is the second one, improved by introducing the concept of digital modulation, which means converting the voice(only) into digital code(in your phone) and then into analog signals(imagine that it flys in the air). Being digital, they overcame some of the limitations of 1G, such as it omits the radio power from handsets making life more healthier, and it has enhanced privacy.

2.5G is a transition of 2G and 3G. In 2.5G, the most popular services like SMS (short messaging service)

, GPRS, EDGE, High Speed Circuit switched data, and more had been introduced.

3G is the current generation of mobile telecommunication standards. It allows simultaneous use of speech and data services and offers data rates of up to 2 Mbps, which provide servcies like video calls, mobile TV, mobile Internet and downloading.   There are a bunch of technologies that fall under 3G, like WCDMA, EV-DO, and HSPA and others.

In telecommunications, 4G is the fourth generation of cellular wireless standards. It is a successor to the 3G and 2G families of standards. In 2008, the ITU-R organization specified the IMT-Advanced (International Mobile Telecommunications Advanced) requirements for 4G standards, setting peak speed requirements for 4G service at 100 Mbit/s for high mobility communication (such as from trains and cars) and 1 Gbit/s for low mobility communication (such as pedestrians and stationary users)

A 4G system is expected to provide a comprehensive and secure all-IP based mobile broadband solution to laptop computer wireless modems, smartphones, and other mobile devices. Facilities such as ultra-broadband Internet access, IP telephony, gaming services, and streamed multimedia may be provided to users.

PRE-4G technologies such as mobile WiMAX and Long term evolution (LTE) have been on the market since 2006 and 2009 respectively, and are often branded as 4G. The current versions of these technologies did not fulfill the original ITU-R requirements of data rates approximately up to 1 Gbit/s for 4G systems. Marketing materials use 4G as a description for LTE and Mobile-WiMAX in their current forms.

Definition of above mentioned terms/words are taken from different professionals and web sources.

It is possible that you may found some differences in the above definitions as it depend on professional to professional.  In this case, you may share your views with us or you can search through Internet for more clarification

 

Best Wishes,

Setting up a SFTP Server on Windows

I recently had to create an SFTP server on our work development system, and after doing a fair bit of Googling on the topic found a good solution. The solution is a combination of research done at differnt sites. It is this solution that I am sharing in hopes that it will help someone else.

This tutorial will help you turn your Windows based system into a SecureFTP server.

Background

Secure Shell (SSH) is a program that lets you log into another computer over a network, to execute commands in a remote machine, and to move files from one machine to another. It provides strong authentication and secure communications over insecure channels. When using ssh, the entire login session, including transmission of password, is encrypted and therefore is very secure.

You may have noticed that many webhosts allow ssh access. This means that you can login to their webserver and execute many UNIX commands (the ones they allow you access to) on your account. Not only can you connect to other computers that provide SSH access, but you can also allow others to connect to your computer using SSH.

To take this one step further, you can also turn your Windows PC into a Secure FTP (SFTP) server. SFTP is a program that uses SSH to transfer files. Unlike standard FTP, it encrypts both commands and data, preventing passwords and sensitive information from being transmitted in clear text over the Internet. It is similar to FTP, but because it uses a different protocol, you must use a FTP client that supports SFTP (more about that later).

Installing SSH on Windows

Most UNIX based systems (Linux and OSX) come with SSH preinstalled, so connecting to a remote host is very easy. However, if you run a Windows system, you need to download some additional software to make the SSH programs available to you. Fortunately a free open-source project called SSHWindows, provides a nice Windows installer that will setup the SSH client and Server on your system.

Your first step will be to download the Binary Installer Release from SSHWindows. Once downloaded, run the installer and be sure to install both the client and server components.

Configure the SSH Server

In this next step, I have summarized the information that is included with the readme.txt that is included with SSHWindows (it can be found in c:\program files\openssh\docs)

Your first configuration step is to set up the passwd file. You will need to set up the passwd file before any logins can take place.

Passwd creation is relatively easy and can be done using two programs that are included with SSHWindows – mkgroup and mkpasswd. Both of these programs are located in the c:\program files\openssh\bin directory.

To begin creating the group and passwd files, open a command prompt window and navigate to the c:\program files\openssh directory.

You must first create a group file. To add all local groups on your computer to the group file, type the command as shown below:

mkgroup -l >> ..\etc\group

You will now need to create a passwd file. Any users in the passwd file will be able to log on with SSH. For this reason, it is recommended that you add users individually with the -u switch. To add a user to the passwd file type the command shown below:

mkpasswd -l -u username >> ..\etc\passwd

NOTE: the username specified above must be an existing windows login account.

Creating Home Directories for you Users

In the passwd file, you will notice that the user’s home directory is set as /home/username, with username being the name of the account. In the default install, the /home directory is set to the default profile directory for all users. This is usually c:\documents and settings.

If you want to change this location you will need to edit the passwd file. The passwd file is in plain text and can be edited in Notepad or any text editor. The last two entries for each user are safe to edit by hand. The second to last entry (/home/username) can be replaced with any other directory to act as that user’s home directory. It’s worth noting that when you run SSH on windows, you are actually running SSH in a scaled down version of cygwin, which is a Unix emulator for Windows. So, if you will be placing the user somewhere outside the default directory for their Windows profile, you will need to use the cygdrive notation.

To access any folder on any drive letter, add /cygdrive/DRIVELETTER/ at the beginning of the folder path. As an example, to access the winnt\system32 directory on the *c:* drive you would use the path:

*/cygdrive/c/winnt/system32*

Connecting to your SFTP Server

To connect to your new SFTP server, you will need to download an FTP client that supports SFTP. I use Filezilla which is a nice free FTP and SFTP client. You might also try WinSCP which is another free SFTP client.

To test if your server is running, create a new connection in your client and specify SFTP as the server type, 22 as the port, and localhost or 127.0.0.1 as the server name. You will also need to provide the user account and password for any account that you added to your passwd file. Now connect to the server. If all went well, you should see a directory listing where you pointed the home folder to. If not, there are a couple of things to check. Make sure your Windows firewall is set to allow traffic over port 22 and finally double check your passwd file to make sure that the account you added is actually there.

Security

Because SSH allows access to only Windows user accounts, you can restrict access based upon NTFS file permissions. As such, SFTP does not provide for chroot jails (a Unix method for locking a user to his/her home directory). Simply lock down your filesystem for that user, and SFTP will respect that.

Summary

In the end, setting up an SFTP server turned out to be a very effortless task. With a couple of open source programs and a couple of command-line commands, you can up and running in no time at all! Try this link for info on a free mail server on Windows.

I’m aware that a certain percentage of people who get to this page don’t find the info they need. I don’t consider Digital Media Minute an overly commercial site, but I’ve decided to include a link to a product that will help some of those people.

If you are interested in setting up a secure web server and/or self-hosting, including installing and configuring either IIS, Apache or PWS, router configuration. etc.

Source :

http://www.digitalmediaminute.com

Secured SFTP using FileZilla

Once you have learned the basic FTP, it is time to learn how to use SFTP. The correct term for this is SSH File Transfer Protocol (but loosely referred to as Secure FTP or SFTP). It means that connection password and data is transmitted securely over the internet in encrypted form. This is different from regular FTP where data is transmitted without encryption, and a hacker with packet sniffer can intercept your data. Hacker can still intercept bits from Secure FTP, the difference is that the bits are encrypted.

We’ll show you have to use SFTP using FileZilla for Windows. (Mac users can try CyberDuck).

To connect using secure SFTP using FileZilla

Step 1: Click the File icon
Step 2: Click “New Site” and give it a name
Step 3: Enter the domain name
Step 4: Select “SFTP over SSH2″ (Version 2 of the SSH protocol is the most often used).
Step 5: Select “Normal” login type
Step 6: Enter username and password
Step 7: Click Connect

To ensure that you are connected via SFTP, you should see “initializing SFTP connection” in the Filezilla console and see a lock icon in the FileZilla status bar …

Not Working?

You need SSH access in order to use SFTP over SSH. Not all webhost will provide this access. Others may provide SSH, but you have to explicitly apply for it. Try connecting using regular FTP. If regular FTP work, but FTP over SSH does not, then contact your webhost about SSH access.

Source :

http://www.learnwebdesignonline.com