SetIsclAuthenticationData(IntPtr,int) Method

Summary

Sets the authentication data used during the mutual authentication process.

Syntax

C++

public void SetIsclAuthenticationData( 
   IntPtr buffer, 
   int length 
)

Public Overloads Sub SetIsclAuthenticationData( _ 
   ByVal buffer As IntPtr, _ 
   ByVal length As Integer _ 
)

public: 
void SetIsclAuthenticationData(  
   IntPtr buffer, 
   int length 
)

Parameters

buffer
Pointer to a buffer that holds the authentication data.

length
The length of the authentication data, in bytes. The method will fail if this is not in the range 1 to 128.

Remarks

Every ISCL-compliant entity must have between 1 and 128 bytes of authentication data. This authentication data is exchanged between the client and the server during the mutual authentication process. This method sets an array of 1 to 128 bytes that contains the authentication data. The authentication data is data exchanged in plain text. After the mutual authentication process, the communication entities can verify the authentication data of the other entity (client or server) and, if the authentication data is wrong, can close the connection.

Example

This is a comprehensive sample that shows how to use DICOM Secure communication using ISCL.

using Leadtools; 
using Leadtools.Dicom; 
 
[StructLayout(LayoutKind.Sequential)] 
public struct MSG 
{ 
   public IntPtr hwnd; 
   public uint message; 
   public IntPtr wParam; 
   public IntPtr lParam; 
   public uint time; 
   public System.Drawing.Point p; 
} 
 
public enum WaitReturn 
{ 
   Complete, 
   Timeout, 
} 
 
class Utils 
{ 
   [DllImport("user32.dll")] 
   [return: MarshalAs(UnmanagedType.Bool)] 
   static extern bool PeekMessage(out MSG lpMsg, IntPtr hWnd, 
                                  uint wMsgFilterMin, uint wMsgFilterMax, 
                                  uint wRemoveMsg); 
 
   [DllImport("user32.dll")] 
   static extern bool TranslateMessage([In] ref MSG lpMsg); 
   [DllImport("user32.dll")] 
   static extern IntPtr DispatchMessage([In] ref MSG lpmsg); 
 
   const uint PM_REMOVE = 1; 
 
   public static WaitReturn WaitForComplete(double mill, WaitHandle wh) 
   { 
      TimeSpan goal = new TimeSpan(DateTime.Now.AddMilliseconds(mill).Ticks); 
 
      do 
      { 
         MSG msg = new MSG(); 
 
         if (PeekMessage(out msg, IntPtr.Zero, 0, 0, PM_REMOVE)) 
         { 
            TranslateMessage(ref msg); 
            DispatchMessage(ref msg); 
         } 
 
         if (wh.WaitOne(new TimeSpan(0, 0, 0), false)) 
         { 
            return WaitReturn.Complete; 
         } 
 
         if (goal.CompareTo(new TimeSpan(DateTime.Now.Ticks)) < 0) 
         { 
            return WaitReturn.Timeout; 
         } 
 
      } while (true); 
   } 
 
   public static void SetupISCL(DicomNet net, string authData) 
   { 
      net.SetIsclMutualAuthenticationAlgorithm(DicomIsclMutualAuthenticationMode.ThreePFourW); 
      net.SetIsclMutualAuthenticationKey(1, 11619789628100321); 
      net.SetIsclMutualAuthenticationKey(2, 34217865672122111); 
      net.SetIsclMutualAuthenticationKey(3, 1605935625518899689); 
      net.SetIsclMutualAuthenticationKey(4, 138217077775855676); 
      net.SetIsclMutualAuthenticationKey(5, 9117318694593010212); 
      net.SetIsclMutualAuthenticationKey(6, 3485297985488245687); 
      net.SetIsclMutualAuthenticationKey(7, 1533287511573403981); 
      net.SetIsclMutualAuthenticationKey(8, 5604839976916070822); 
      net.SetIsclIndexForMutualAuthentication(1); 
 
      net.SetIsclDefaultEncryptionMode(DicomIsclEncryptionMethodType.DesCbc); 
      net.SetIsclDefaultSigningMode(DicomIsclSigningMethodType.Md5); 
      net.SetIsclEncryptionKey(1, 8079278526052745737); 
      net.SetIsclEncryptionKey(2, 1312864321990916052); 
      net.SetIsclEncryptionKey(3, 7190959962252002117); 
      net.SetIsclEncryptionKey(4, 3619524191167482890); 
      net.SetIsclEncryptionKey(5, 3466658849848898336); 
      net.SetIsclEncryptionKey(6, 8474124475946342520); 
      net.SetIsclEncryptionKey(7, 7725464453540259890); 
      net.SetIsclEncryptionKey(8, 4320705344832296668); 
      net.SetIsclEncryptionKeyIndex(1); 
 
      net.SetIsclMaxMessageLength(1024000); 
      net.SetIsclMaxCommunicationBlockLength(8129); 
 
      byte[] data = new ASCIIEncoding().GetBytes(authData); 
 
      net.SetIsclAuthenticationData(data, data.GetLength(0)); 
   } 
} 
 
// 
// Secure client (ISCL) 
// 
public class Client : DicomNet 
{ 
   readonly AutoResetEvent waitEvent = new AutoResetEvent(false); 
 
   public Client() 
       : base(null, DicomNetSecurityMode.Iscl) 
   { 
      const string authData = "LEAD client ISCL"; 
 
      Utils.SetupISCL(this, authData); 
   } 
 
   public bool Wait() 
   { 
      WaitReturn ret = Utils.WaitForComplete((2 * 60) * 1000, waitEvent); 
 
      return (ret == WaitReturn.Complete); 
   } 
 
   protected override void OnConnect(DicomExceptionCode error) 
   { 
      waitEvent.Set(); 
   } 
 
   protected override void OnSecureLinkReady(DicomExceptionCode error) 
   { 
      Console.WriteLine("Iscl Peer Encryption is               : {0}", GetIsclPeerEncryption()); 
      Console.WriteLine("Iscl Peer Mac                         : {0}", GetIsclPeerMac()); 
      Console.WriteLine("Iscl Communication Block Length is    : {0}", GetIsclCommunicationBlockLength()); 
      Console.WriteLine("Iscl Index For Encryption             : {0}", GetIsclIndexForEncryption()); 
      Console.WriteLine("Is Iscl Queue Empty                   : {0}", IsIsclQueueEmpty()); 
      Console.WriteLine("Iscl Index For Mutual Authentication  : {0}", GetIsclIndexForMutualAuthentication()); 
      Console.WriteLine("Iscl Status is                        : {0}", GetIsclStatus()); 
      //We can also call  GetIsclPeerAuthenticationData() to Get the Peer Authentication Data 
      waitEvent.Set(); 
   } 
 
   protected override bool GetChallengeIscl(ref long challenge, long parameter) 
   { 
      challenge = 0x0123456789ABCDE1; 
      return true; 
   } 
 
   protected override bool InternalAuthenticateIscl(long challenge, ref long response, long parameter) 
   { 
      response = challenge + 1; 
      return true; 
   } 
 
   protected override bool ExternalAuthenticateIscl(long challenge, long response, long parameter) 
   { 
      if (response == (challenge + 1)) 
         return true; 
 
      return false; 
   } 
 
   protected override void OnReceiveAssociateAccept(DicomAssociate association) 
   { 
      waitEvent.Set(); 
   } 
 
   protected override void OnReceiveReleaseResponse() 
   { 
      waitEvent.Set(); 
   } 
 
   protected override void OnReceiveCEchoResponse(byte presentationID, int messageID, string affectedClass, DicomCommandStatusType status) 
   { 
      Debug.Assert(presentationID == 1, "Presentation id should be 1"); 
      Debug.Assert(messageID == 1, "Message ID should be 1"); 
      Debug.Assert(affectedClass == DicomUidType.VerificationClass, "Affected class should be " + DicomUidType.VerificationClass); 
      waitEvent.Set(); 
   } 
}; 
 
// 
// Secure server client (ISCL) 
// 
public class ServerConnection : DicomNet 
{ 
   public ServerConnection() 
       : base(null, DicomNetSecurityMode.Iscl) 
   { 
      const string authData = "LEAD ServerConnection ISCL"; 
      Utils.SetupISCL(this, authData); 
   } 
 
   protected override bool GetChallengeIscl(ref long challenge, long parameter) 
   { 
      challenge = 0x0123456789ABCDE1; 
      return true; 
   } 
 
   protected override bool InternalAuthenticateIscl(long challenge, ref long response, long parameter) 
   { 
      response = challenge + 1; 
      return true; 
   } 
 
   protected override bool ExternalAuthenticateIscl(long challenge, long response, long parameter) 
   { 
      if (response == challenge + 1) 
         return true; 
 
      return false; 
   } 
 
   protected override void OnReceiveAssociateRequest(DicomAssociate association) 
   { 
      DicomAssociate retAssociation = new DicomAssociate(false); 
 
      Debug.Assert(association.Called == "ServerTest", "Called AETitle should be ServerTest"); 
      Debug.Assert(association.Calling == "ClientTest", "Calling AETitle should be ClientTest"); 
      Debug.Assert(association.ImplementClass == "1.2.840.114257.1", "Implementation class should be 1.2.840.114257.1"); 
      Debug.Assert(association.ImplementationVersionName == "1", "Implementation version should be 1"); 
      Debug.Assert(association.MaxLength == 0x100000, "Max length should be 0x100000"); 
      Debug.Assert(association.GetAbstract(1) == DicomUidType.VerificationClass, "Presentation index 1 should be " + DicomUidType.VerificationClass); 
      Debug.Assert(association.GetTransfer(1, 0) == DicomUidType.ImplicitVRLittleEndian, "Abstract Syntax (1,0) should be " + DicomUidType.ImplicitVRLittleEndian); 
 
      // 
      // Build our Association Accept 
      // 
      retAssociation.Called = association.Called; 
      retAssociation.Calling = association.Calling; 
      retAssociation.ImplementClass = association.ImplementClass; 
      retAssociation.ImplementationVersionName = association.ImplementationVersionName; 
      for (int x = 0; x < association.PresentationContextCount; x++) 
      { 
         byte id = association.GetPresentationContextID(x); 
         string abSyntax = association.GetAbstract(id); 
         string trSyntax = DicomUidType.ImplicitVRLittleEndian; 
 
         retAssociation.AddPresentationContext(id, 0, abSyntax); 
         if (association.GetTransferCount(id) > 0) 
         { 
            trSyntax = association.GetTransfer(id, 0); 
         } 
 
         retAssociation.AddTransfer(id, trSyntax); 
      } 
      SendAssociateAccept(retAssociation); 
   } 
 
   protected override void OnReceiveReleaseRequest() 
   { 
      SendReleaseResponse(); 
   } 
 
   protected override void OnReceiveCEchoRequest(byte presentationID, int messageID, string affectedClass) 
   { 
      Debug.Assert(presentationID == 1, "Presentation id should be 1"); 
      Debug.Assert(messageID == 1, "Message ID should be 1"); 
      Debug.Assert(affectedClass == DicomUidType.VerificationClass, "Affected class should be " + DicomUidType.VerificationClass); 
 
      SendCEchoResponse(presentationID, messageID, DicomUidType.VerificationClass, DicomCommandStatusType.Success); 
   } 
}; 
 
public class Server : DicomNet 
{ 
   readonly AutoResetEvent waitEvent = new AutoResetEvent(false); 
 
   public Server() 
       : base(null, DicomNetSecurityMode.None) 
   { 
   } 
 
   protected override void OnAccept(DicomExceptionCode error) 
   { 
      ServerConnection client = new ServerConnection(); 
 
      Accept(client); 
   } 
} 
 
public void ISCLSecuritySample() 
{ 
   DicomEngine.Startup(); 
   DicomNet.Startup(); 
 
   using (Server server = new Server()) 
   { 
      using (Client client = new Client()) 
      { 
         server.Listen("127.0.0.1", 106, 1); // start server 
         client.Connect("", 1006, "127.0.0.1", 106); // connect to secure server 
 
         if (!client.Wait()) // wait for connection to finish 
         { 
            Debug.Fail("Connection timed out"); 
         } 
         Debug.Assert(client.IsConnected(), "Client not connected"); 
 
         // 
         // Wait for authenication 
         // 
         if (!client.Wait()) 
         { 
            Debug.Fail("Connection timed out waiting for authenication"); 
         } 
 
         // If secure link is established you can now do your regular 
         // dicom communications. 
 
         // 
         // Send associate request 
         // 
         DicomAssociate associate = new DicomAssociate(true); 
 
         associate.Called = "ServerTest"; 
         associate.Calling = "ClientTest"; 
         associate.ImplementClass = "1.2.840.114257.1"; 
         associate.ImplementationVersionName = "1"; 
         associate.MaxLength = 0x100000; 
         associate.AddPresentationContext(1, 0, DicomUidType.VerificationClass); 
         associate.AddTransfer(1, DicomUidType.ImplicitVRLittleEndian); 
         client.SendAssociateRequest(associate); 
         if (!client.Wait()) // wait for connection to finish 
         { 
            Debug.Fail("SendAssociateRequest timed out"); 
         } 
 
         // 
         // Send Echo Request 
         // 
         byte pid = client.Association.FindAbstract(DicomUidType.VerificationClass); 
 
         client.SendCEchoRequest(pid, 1, DicomUidType.VerificationClass); 
         if (!client.Wait()) // wait for connection to finish 
         { 
            Debug.Fail("SendCEchoRequest timed out"); 
         } 
 
         // 
         // SendReleaseRequest 
         // 
         client.SendReleaseRequest(); 
         if (!client.Wait()) // wait for connection to finish 
         { 
            Debug.Fail("SendReleaseRequest timed out"); 
         } 
 
         client.CloseForced(true); 
      } 
      server.CloseForced(true); 
   } 
 
   DicomEngine.Shutdown(); 
   DicomNet.Shutdown(); 
}

Imports Leadtools 
Imports Leadtools.Dicom 
 
<StructLayout(LayoutKind.Sequential)> 
Public Structure MSG 
   Public hwnd As IntPtr 
   Public message As UInteger 
   Public wParam As IntPtr 
   Public lParam As IntPtr 
   Public time As UInteger 
   Public p As System.Drawing.Point 
End Structure 
 
Public Enum WaitReturn 
   Complete 
   Timeout 
End Enum 
 
Private Class Utils 
   <DllImport("user32.dll")> 
   Shared Function PeekMessage(<System.Runtime.InteropServices.Out()> ByRef lpMsg As MSG, ByVal hWnd As IntPtr, ByVal wMsgFilterMin As UInteger, 
                                  ByVal wMsgFilterMax As UInteger, ByVal wRemoveMsg As UInteger) As <MarshalAs(UnmanagedType.Bool)> Boolean 
   End Function 
 
   <DllImport("user32.dll")> 
   Shared Function TranslateMessage(ByRef lpMsg As MSG) As Boolean 
   End Function 
   <DllImport("user32.dll")> 
   Shared Function DispatchMessage(ByRef lpmsg As MSG) As IntPtr 
   End Function 
 
   Private Const PM_REMOVE As UInteger = 1 
 
   Public Shared Function WaitForComplete(ByVal mill As Double, ByVal wh As WaitHandle) As WaitReturn 
      Dim goal As TimeSpan = New TimeSpan(DateTime.Now.AddMilliseconds(mill).Ticks) 
 
      Do 
         Dim msg As MSG = New MSG() 
 
         If PeekMessage(msg, IntPtr.Zero, 0, 0, PM_REMOVE) Then 
            TranslateMessage(msg) 
            DispatchMessage(msg) 
         End If 
 
         If wh.WaitOne(New TimeSpan(0, 0, 0), False) Then 
            Return WaitReturn.Complete 
         End If 
 
         If goal.CompareTo(New TimeSpan(DateTime.Now.Ticks)) < 0 Then 
            Return WaitReturn.Timeout 
         End If 
 
      Loop While True 
   End Function 
 
   Public Shared Sub SetupISCL(ByVal net As DicomNet, ByVal authData As String) 
      net.SetIsclMutualAuthenticationAlgorithm(DicomIsclMutualAuthenticationMode.ThreePFourW) 
      net.SetIsclMutualAuthenticationKey(1, 11619789628100321) 
      net.SetIsclMutualAuthenticationKey(2, 34217865672122111) 
      net.SetIsclMutualAuthenticationKey(3, 1605935625518899689) 
      net.SetIsclMutualAuthenticationKey(4, 138217077775855676) 
      net.SetIsclMutualAuthenticationKey(5, 9117318694593010212) 
      net.SetIsclMutualAuthenticationKey(6, 3485297985488245687) 
      net.SetIsclMutualAuthenticationKey(7, 1533287511573403981) 
      net.SetIsclMutualAuthenticationKey(8, 5604839976916070822) 
      net.SetIsclIndexForMutualAuthentication(1) 
 
      net.SetIsclDefaultEncryptionMode(DicomIsclEncryptionMethodType.DesCbc) 
      net.SetIsclDefaultSigningMode(DicomIsclSigningMethodType.Md5) 
      net.SetIsclEncryptionKey(1, 8079278526052745737) 
      net.SetIsclEncryptionKey(2, 1312864321990916052) 
      net.SetIsclEncryptionKey(3, 7190959962252002117) 
      net.SetIsclEncryptionKey(4, 3619524191167482890) 
      net.SetIsclEncryptionKey(5, 3466658849848898336) 
      net.SetIsclEncryptionKey(6, 8474124475946342520) 
      net.SetIsclEncryptionKey(7, 7725464453540259890) 
      net.SetIsclEncryptionKey(8, 4320705344832296668) 
      net.SetIsclEncryptionKeyIndex(1) 
 
      net.SetIsclMaxMessageLength(1024000) 
      net.SetIsclMaxCommunicationBlockLength(8129) 
 
      Dim data() As Byte = New ASCIIEncoding().GetBytes(authData) 
 
      net.SetIsclAuthenticationData(data, data.GetLength(0)) 
   End Sub 
End Class 
 
' 
' Secure client (ISCL) 
' 
Public Class Client : Inherits DicomNet 
   Private waitEvent As AutoResetEvent = New AutoResetEvent(False) 
 
   Public Sub New() 
      MyBase.New(Nothing, DicomNetSecurityMode.Iscl) 
      Const authData As String = "LEAD client ISCL" 
 
      Utils.SetupISCL(Me, authData) 
   End Sub 
 
   Public Function Wait() As Boolean 
      Dim ret As WaitReturn = Utils.WaitForComplete((2 * 60) * 1000, waitEvent) 
 
      Return (ret = WaitReturn.Complete) 
   End Function 
 
   Protected Overrides Sub OnConnect(ByVal [error] As DicomExceptionCode) 
      waitEvent.Set() 
   End Sub 
 
   Protected Overrides Sub OnSecureLinkReady(ByVal [error] As DicomExceptionCode) 
      Console.WriteLine("Iscl Peer Encryption is               : {0}", GetIsclPeerEncryption()) 
      Console.WriteLine("Iscl Peer Mac                         : {0}", GetIsclPeerMac()) 
      Console.WriteLine("Iscl Communication Block Length is    : {0}", GetIsclCommunicationBlockLength()) 
      Console.WriteLine("Iscl Index For Encryption             : {0}", GetIsclIndexForEncryption()) 
      Console.WriteLine("Is Iscl Queue Empty                   : {0}", IsIsclQueueEmpty()) 
      Console.WriteLine("Iscl Index For Mutual Authentication  : {0}", GetIsclIndexForMutualAuthentication()) 
      Console.WriteLine("Iscl Status is                        : {0}", GetIsclStatus()) 
      'We can also call  GetIsclPeerAuthenticationData() to Get the Peer Authentication Data 
      waitEvent.Set() 
   End Sub 
 
   Protected Overrides Function GetChallengeIscl(ByRef challenge As Long, ByVal parameter As Long) As Boolean 
      challenge = &H123456789ABCDE1 
      Return True 
   End Function 
 
   Protected Overrides Function InternalAuthenticateIscl(ByVal challenge As Long, ByRef response As Long, ByVal parameter As Long) As Boolean 
      response = challenge + 1 
      Return True 
   End Function 
 
   Protected Overrides Function ExternalAuthenticateIscl(ByVal challenge As Long, ByVal response As Long, ByVal parameter As Long) As Boolean 
      If response = (challenge + 1) Then 
         Return True 
      End If 
 
      Return False 
   End Function 
 
   Protected Overrides Sub OnReceiveAssociateAccept(ByVal association As DicomAssociate) 
      waitEvent.Set() 
   End Sub 
 
   Protected Overrides Sub OnReceiveReleaseResponse() 
      waitEvent.Set() 
   End Sub 
 
   Protected Overrides Sub OnReceiveCEchoResponse(ByVal presentationID As Byte, ByVal messageID As Integer, ByVal affectedClass As String, ByVal status As DicomCommandStatusType) 
      Debug.Assert(presentationID = 1, "Presentation id should be 1") 
      Debug.Assert(messageID = 1, "Message ID should be 1") 
      Debug.Assert(affectedClass = DicomUidType.VerificationClass, "Affected class should be " & DicomUidType.VerificationClass) 
      waitEvent.Set() 
   End Sub 
End Class 
 
' 
' Secure server client (ISCL) 
' 
Public Class ServerConnection : Inherits DicomNet 
   Public Sub New() 
      MyBase.New(Nothing, DicomNetSecurityMode.Iscl) 
      Const authData As String = "LEAD ServerConnection ISCL" 
      Utils.SetupISCL(Me, authData) 
   End Sub 
 
   Protected Overrides Function GetChallengeIscl(ByRef challenge As Long, ByVal parameter As Long) As Boolean 
      challenge = &H123456789ABCDE1 
      Return True 
   End Function 
 
   Protected Overrides Function InternalAuthenticateIscl(ByVal challenge As Long, ByRef response As Long, ByVal parameter As Long) As Boolean 
      response = challenge + 1 
      Return True 
   End Function 
 
   Protected Overrides Function ExternalAuthenticateIscl(ByVal challenge As Long, ByVal response As Long, ByVal parameter As Long) As Boolean 
      If response = challenge + 1 Then 
         Return True 
      End If 
 
      Return False 
   End Function 
 
   Protected Overrides Sub OnReceiveAssociateRequest(ByVal association As DicomAssociate) 
      Dim retAssociation As New DicomAssociate(False) 
 
      Debug.Assert(association.Called = "ServerTest", "Called AETitle should be ServerTest") 
      Debug.Assert(association.Calling = "ClientTest", "Calling AETitle should be ClientTest") 
      Debug.Assert(association.ImplementClass = "1.2.840.114257.1", "Implementation class should be 1.2.840.114257.1") 
      Debug.Assert(association.ImplementationVersionName = "1", "Implementation version should be 1") 
      Debug.Assert(association.MaxLength = &H100000, "Max length should be 0x100000") 
      Debug.Assert(association.GetAbstract(1) = DicomUidType.VerificationClass, "Presentation index 1 should be " & DicomUidType.VerificationClass) 
      Debug.Assert(association.GetTransfer(1, 0) = DicomUidType.ImplicitVRLittleEndian, "Abstract Syntax (1,0) should be " & DicomUidType.ImplicitVRLittleEndian) 
 
      ' 
      ' Build our Association Accept 
      ' 
      retAssociation.Called = association.Called 
      retAssociation.Calling = association.Calling 
      retAssociation.ImplementClass = association.ImplementClass 
      retAssociation.ImplementationVersionName = association.ImplementationVersionName 
      For x As Integer = 0 To association.PresentationContextCount - 1 
         Dim id As Byte = association.GetPresentationContextID(x) 
         Dim abSyntax As String = association.GetAbstract(id) 
         Dim trSyntax As String = DicomUidType.ImplicitVRLittleEndian 
 
         retAssociation.AddPresentationContext(id, 0, abSyntax) 
         If association.GetTransferCount(id) > 0 Then 
            trSyntax = association.GetTransfer(id, 0) 
         End If 
 
         retAssociation.AddTransfer(id, trSyntax) 
      Next x 
      SendAssociateAccept(retAssociation) 
   End Sub 
 
   Protected Overrides Sub OnReceiveReleaseRequest() 
      SendReleaseResponse() 
   End Sub 
 
   Protected Overrides Sub OnReceiveCEchoRequest(ByVal presentationID As Byte, ByVal messageID As Integer, ByVal affectedClass As String) 
      Debug.Assert(presentationID = 1, "Presentation id should be 1") 
      Debug.Assert(messageID = 1, "Message ID should be 1") 
      Debug.Assert(affectedClass = DicomUidType.VerificationClass, "Affected class should be " & DicomUidType.VerificationClass) 
 
      SendCEchoResponse(presentationID, messageID, DicomUidType.VerificationClass, DicomCommandStatusType.Success) 
   End Sub 
End Class 
 
Public Class Server : Inherits DicomNet 
   Public Sub New() 
      MyBase.New(Nothing, DicomNetSecurityMode.None) 
   End Sub 
 
   Protected Overrides Sub OnAccept(ByVal [error] As DicomExceptionCode) 
      Dim client As ServerConnection = New ServerConnection() 
 
      Accept(client) 
   End Sub 
End Class 
 
 
Public Sub ISCLSecuritySample() 
   DicomEngine.Startup() 
   DicomNet.Startup() 
 
   Using server As New Server() 
      Using client As New Client() 
         server.Listen("127.0.0.1", 106, 1) ' start server 
         client.Connect("", 1006, "127.0.0.1", 106) ' connect to secure server 
 
         If (Not client.Wait()) Then ' wait for connection to finish 
            Debug.Fail("Connection timed out") 
         End If 
         Debug.Assert(client.IsConnected(), "Client not connected") 
 
         ' 
         ' Wait for authenication 
         ' 
         If (Not client.Wait()) Then 
            Debug.Fail("Connection timed out waiting for authenication") 
         End If 
 
         ' If secure link is established you can now do your regular 
         ' dicom communications. 
 
         ' 
         ' Send associate request 
         ' 
         Dim associate As New DicomAssociate(True) 
 
         associate.Called = "ServerTest" 
         associate.Calling = "ClientTest" 
         associate.ImplementClass = "1.2.840.114257.1" 
         associate.ImplementationVersionName = "1" 
         associate.MaxLength = &H100000 
         associate.AddPresentationContext(1, 0, DicomUidType.VerificationClass) 
         associate.AddTransfer(1, DicomUidType.ImplicitVRLittleEndian) 
         client.SendAssociateRequest(associate) 
         If (Not client.Wait()) Then ' wait for connection to finish 
            Debug.Fail("SendAssociateRequest timed out") 
         End If 
 
         ' 
         ' Send Echo Request 
         ' 
         Dim pid As Byte = client.Association.FindAbstract(DicomUidType.VerificationClass) 
 
         client.SendCEchoRequest(pid, 1, DicomUidType.VerificationClass) 
         If (Not client.Wait()) Then ' wait for connection to finish 
            Debug.Fail("SendCEchoRequest timed out") 
         End If 
 
         ' 
         ' SendReleaseRequest 
         ' 
         client.SendReleaseRequest() 
         If (Not client.Wait()) Then ' wait for connection to finish 
            Debug.Fail("SendReleaseRequest timed out") 
         End If 
 
         client.CloseForced(True) 
      End Using 
      server.CloseForced(True) 
   End Using 
 
   DicomEngine.Shutdown() 
   DicomNet.Shutdown() 
End Sub