잊지 않겠습니다.

'TCP/IP'에 해당되는 글 3건

  1. 2010.01.05 0010. CSSocketClient
  2. 2010.01.05 0009. CSSocketServer
  3. 2009.08.02 TCP/IP Port 정보 List
Client 소스는 좀더 간단하다. Server의 경우에는 Bind와 Listen의 절차를 거치고, Listen에서 BeginListen, EndListen으로
AsyncCallback을 통해야지 되지만, Client의 경우에는 간단히 Connect만으로 가능하고, 하나의 Client에서는 역시 하나의
연결정도만 신경을 쓰면 되기 때문에 더욱더 편한 개발이 가능하다.

솔찍한 생각으로 예제 소스이긴 하지만, UI단만 조금 붙여버리면 거의 일반 프로그램들과 큰 차이가 안보인다.
Socket의 Close시에 Shutdown으로 Socket을 정리하는 부분에 신경을 쓰면 될 것 같다.


/****************************** Module Header ******************************\
* Module Name:	Program.cs
* Project:		CSSocketClient
* Copyright (c) Microsoft Corporation.
* 
* Sockets are an application programming interface(API) in an operating system
* used for in inter-process communication. Sockets constitute a mechanism for
* delivering incoming data packets to the appropriate application process or
* thread, based on a combination of local and remote IP addresses and port
* numbers. Each socket is mapped by the operational system to a communicating
* application process or thread.
*
*
* .NET supplies a Socket class which implements the Berkeley sockets interface.
* It provides a rich set of methods and properties for network communications. 
* Socket class allows you to perform both synchronous and asynchronous data
* transfer using any of the communication protocols listed in the ProtocolType
* enumeration. It supplies the following types of socket:
*
* Stream: Supports reliable, two-way, connection-based byte streams without 
* the duplication of data and without preservation of boundaries.
*
* Dgram:Supports datagrams, which are connectionless, unreliable messages of
* a fixed (typically small) maximum length. 
*
* Raw: Supports access to the underlying transport protocol.Using the 
* SocketTypeRaw, you can communicate using protocols like Internet Control 
* Message Protocol (Icmp) and Internet Group Management Protocol (Igmp). 
*
* Rdm: Supports connectionless, message-oriented, reliably delivered messages, 
* and preserves message boundaries in data. 
*
* Seqpacket:Provides connection-oriented and reliable two-way transfer of 
* ordered byte streams across a network.
*
* Unknown:Specifies an unknown Socket type.
* 
* This source is subject to the Microsoft Public License.
* See http://www.microsoft.com/opensource/licenses.mspx#Ms-PL.
* All other rights reserved.
* 
* THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, 
* EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED 
* WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
\***************************************************************************/

#region Using directives
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Security;
using System.Security.Permissions;
#endregion


public class Program
{
    static void Main(string[] args)
    {
        // Receiving byte array 
        byte[] bytes = new byte[1024];
        try
        {
            // Create one SocketPermission for socket access restrictions
            SocketPermission permission = new SocketPermission(
                NetworkAccess.Connect,    // Connection permission
                TransportType.Tcp,        // Defines transport types
                "",                       // Gets the IP addresses
                SocketPermission.AllPorts // All ports
                );

            // Ensures the code to have permission to access a Socket
            permission.Demand();

            // Resolves a host name to an IPHostEntry instance           
            IPHostEntry ipHost = Dns.GetHostEntry("");

            // Gets first IP address associated with a localhost
            IPAddress ipAddr = ipHost.AddressList[0];

            // Creates a network endpoint
            IPEndPoint ipEndPoint = new IPEndPoint(ipAddr, 6000);

            // Create one Socket object to setup Tcp connection
            Socket sender = new Socket(
                ipAddr.AddressFamily,// Specifies the addressing scheme
                SocketType.Stream,   // The type of socket 
                ProtocolType.Tcp     // Specifies the protocols 
                );

            sender.NoDelay = true;   // Using the Nagle algorithm

            // Establishes a connection to a remote host
            sender.Connect(ipEndPoint);
            Console.WriteLine("Socket connected to {0}",
                sender.RemoteEndPoint.ToString());

            // Sending message
            // is the sign for end of data
            string theMessage = "Hello World!";
            byte[] msg = 
                Encoding.Unicode.GetBytes(theMessage +"");

            // Sends data to a connected Socket.
            int bytesSend = sender.Send(msg);

            // Receives data from a bound Socket.
            int bytesRec = sender.Receive(bytes);

            // Converts byte array to string
            theMessage = Encoding.Unicode.GetString(bytes, 0, bytesRec);

            // Continues to read the data till data isn't available
            while (sender.Available > 0)
            {
                bytesRec = sender.Receive(bytes);
                theMessage += Encoding.Unicode.GetString(bytes, 0, bytesRec);
            }
            Console.WriteLine("The server reply: {0}", theMessage);

            // Disables sends and receives on a Socket.
            sender.Shutdown(SocketShutdown.Both);

            //Closes the Socket connection and releases all resources
            sender.Close();
        }
        catch (Exception ex)
        {
            Console.WriteLine("Exception: {0}", ex.ToString());
        }
    }
}
Posted by Y2K
,
Socket을 사용해서 TCP/IP 서버를 만들게 되면 개발에서 가장 신경쓰게 되는 것이 Multi-Thread 문제이다.
이부분에 대해서 .NET에서 내놓은 최고의 Solution은 IAsyncCallback interface를 이용해서 BeginXXX 와
EndXXX를 이용하는 방법이다. 이 방법은 WebService client, Stream, Socket 등 데이터를 읽고, 쓰는데에
시간이 소요가 되어 Multi-Thread를 구현해야지 되는 거의 모든 경우에서 사용이 가능하다.

예제 소스는 다음과 같다. IPV6를 사용하는 소스를 IPV4로만 변경시킨 예제이다.


/****************************** Module Header ******************************\
* Module Name:	Program.cs
* Project:		CSSocketServer
* Copyright (c) Microsoft Corporation.
* 
* Sockets are an application programming interface(API) in an operating system
* used for in inter-process communication. Sockets constitute a mechanism for
* delivering incoming data packets to the appropriate application process or
* thread, based on a combination of local and remote IP addresses and port
* numbers. Each socket is mapped by the operational system to a communicating
* application process or thread.
*
*
* .NET supplies a Socket class which implements the Berkeley sockets interface.
* It provides a rich set of methods and properties for network communications. 
* Socket class allows you to perform both synchronous and asynchronous data
* transfer using any of the communication protocols listed in the ProtocolType
* enumeration. It supplies the following types of socket:
*
* Stream: Supports reliable, two-way, connection-based byte streams without 
* the duplication of data and without preservation of boundaries.
*
* Dgram:Supports datagrams, which are connectionless, unreliable messages of
* a fixed (typically small) maximum length. 
*
* Raw: Supports access to the underlying transport protocol.Using the 
* SocketTypeRaw, you can communicate using protocols like Internet Control 
* Message Protocol (Icmp) and Internet Group Management Protocol (Igmp). 
*
* Rdm: Supports connectionless, message-oriented, reliably delivered messages, 
* and preserves message boundaries in data. 
*
* Seqpacket:Provides connection-oriented and reliable two-way transfer of 
* ordered byte streams across a network.
*
* Unknown:Specifies an unknown Socket type.
* 
* This source is subject to the Microsoft Public License.
* See http://www.microsoft.com/opensource/licenses.mspx#Ms-PL.
* All other rights reserved.
* 
* THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, 
* EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED 
* WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
\***************************************************************************/

#region Using Directive
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Threading;
using System.Security;
using System.Security.Permissions;
#endregion


public class Program
{
    static void Main(string[] args)
    {
        // Creates one SocketPermission object for access restrictions
        SocketPermission permission = new SocketPermission(
            NetworkAccess.Accept,     // Allowed to accept connections
            TransportType.Tcp,        // Defines transport types
            "",                       // The IP addresses of local host
            SocketPermission.AllPorts // Specifies all ports
            );

        // Listening Socket object
        Socket sListener = null;

        try
        {
            // Ensures the code to have permission to access a Socket
            permission.Demand();

            // Resolves a host name to an IPHostEntry instance
            IPHostEntry ipHost = Dns.GetHostEntry("");

            ///Get First IPV4 Address
            ///아직까지는 IPV4로 만들지 않으면 외부에서 접근을 못하는 경우가 많다.;
            IPAddress ipAddr = ipHost.AddressList.Where(a => a.AddressFamily != AddressFamily.InterNetworkV6).First();

            // Creates a network endpoint
            IPEndPoint ipEndPoint = new IPEndPoint(ipAddr, 6000);

            // Create one Socket object to listen the incoming connection
            sListener = new Socket(
                ipAddr.AddressFamily,
                SocketType.Stream,
                ProtocolType.Tcp
                );

            // Associates a Socket with a local endpoint
            sListener.Bind(ipEndPoint);

            // Places a Socket in a listening state and specifies the maximum
            // Length of the pending connections queue
            sListener.Listen(10);

            Console.WriteLine("Waiting for a connection on port {0}",
                ipEndPoint);

            // Begins an asynchronous operation to accept an attempt
            AsyncCallback aCallback = new AsyncCallback(AcceptCallback);
            sListener.BeginAccept(aCallback, sListener);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Exception: {0}", ex.ToString());
            return;
        }

        Console.WriteLine("Press the Enter key to exit ...");
        Console.ReadLine();
        
        if (sListener.Connected)
        {
            sListener.Shutdown(SocketShutdown.Receive);
            sListener.Close();
        }
    }


    /// 
    /// Asynchronously accepts an incoming connection attempt and creates
    /// a new Socket to handle remote host communication.
    ///      
    /// the status of an asynchronous operation
    ///  
    public static void AcceptCallback(IAsyncResult ar)
    {
        Socket listener = null;

        // A new Socket to handle remote host communication
        Socket handler = null;
        try
        {
            // Receiving byte array
            byte[] buffer = new byte[1024];
            // Get Listening Socket object
            listener = (Socket)ar.AsyncState;
            // Create a new socket
            handler = listener.EndAccept(ar);

            // Using the Nagle algorithm
            handler.NoDelay = true;

            // Creates one object array for passing data
            object[] obj = new object[2];
            obj[0] = buffer;
            obj[1] = handler;

            // Begins to asynchronously receive data
            handler.BeginReceive(
                buffer,        // An array of type Byt for received data
                0,             // The zero-based position in the buffer 
                buffer.Length, // The number of bytes to receive
                SocketFlags.None,// Specifies send and receive behaviors
                new AsyncCallback(ReceiveCallback),//An AsyncCallback delegate
                obj            // Specifies infomation for receive operation
                );

            // Begins an asynchronous operation to accept an attempt
            AsyncCallback aCallback = new AsyncCallback(AcceptCallback);
            listener.BeginAccept(aCallback, listener);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Exception: {0}", ex.ToString());
        }
    }

    /// 
    /// Asynchronously receive data from a connected Socket.
    /// 
    /// 
    /// the status of an asynchronous operation
    ///  
    public static void ReceiveCallback(IAsyncResult ar)
    {
        try
        {
            // Fetch a user-defined object that contains information
            object[] obj = new object[2];
            obj = (object[])ar.AsyncState;

            // Received byte array
            byte[] buffer = (byte[])obj[0];

            // A Socket to handle remote host communication.
            Socket handler = (Socket)obj[1];

            // Received message
            string content = string.Empty;

            // The number of bytes received.
            int bytesRead = handler.EndReceive(ar);

            if (bytesRead > 0)
            {
                content += Encoding.Unicode.GetString(buffer, 0,
                    bytesRead);
                // If message contains "", finish receiving
                if (content.IndexOf("") > -1)
                {
                    // Convert byte array to string
                    string str =
                        content.TrimEnd(("").ToCharArray());
                    Console.WriteLine(
                        "Read {0} bytes from client.\n Data: {1}",
                        str.Length, str);

                    // Prepare the reply message
                    byte[] byteData =
                        Encoding.Unicode.GetBytes(str);

                    // Sends data asynchronously to a connected Socket
                    handler.BeginSend(byteData, 0, byteData.Length, 0,
                        new AsyncCallback(SendCallback), handler);
                }
                else
                {
                    // Continues to asynchronously receive data
                    byte[] buffernew = new byte[1024];
                    obj[0] = buffernew;
                    obj[1] = handler;
                    handler.BeginReceive(buffernew, 0, buffernew.Length,
                        SocketFlags.None,
                        new AsyncCallback(ReceiveCallback), obj);
                }
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine("Exception: {0}", ex.ToString());
        }
    }

    /// 
    /// Sends data asynchronously to a connected Socket.
    /// 
    /// 
    /// The status of an asynchronous operation
    ///  
    public static void SendCallback(IAsyncResult ar)
    {
        try
        {
            // A Socket which has sent the data to remote host
            Socket handler = (Socket)ar.AsyncState;

            // The number of bytes sent to the Socket
            int bytesSend = handler.EndSend(ar);
            Console.WriteLine(
                "Sent {0} bytes to Client",bytesSend);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Exception: {0}", ex.ToString());
        }
    }
}
Posted by Y2K
,
네트워크 상태를 보다보면 port의 사용 정보를 알고 싶을 때가 많은데...
사용되는 Port의 정보를 알려주는 site. 

정말 별애별 사이트가 다 있다는 증거.;

http://www.seifried.org/security/ports/index.php


Posted by Y2K
,