using System;
using System.Windows.Forms;
using System.Net;
using System.Net.Sockets;
using SnmpSharpNet;
 
namespace AsyncTrapReceiver
{
	public class Form1 : Form
	{
		protected Socket _socket;
		protected byte[] _inbuffer;
		protected IPEndPoint _peerIP;
		private System.Windows.Forms.ListBox listBox1;
		private System.Windows.Forms.CheckBox startCheckBox;
 
		public Form1 ()
		{
			// it is not neccessary to initialize variables to null, but better safe then sorry
			_socket = null;
 
			this.listBox1 = new System.Windows.Forms.ListBox ();
			this.startCheckBox = new System.Windows.Forms.CheckBox ();
			this.SuspendLayout ();
			//
			// listBox1
			//
			this.listBox1.Anchor = ((System.Windows.Forms.AnchorStyles)
				((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) 
				| System.Windows.Forms.AnchorStyles.Left) | System.Windows.Forms.AnchorStyles.Right)));
			this.listBox1.FormattingEnabled = true;
			this.listBox1.Location = new System.Drawing.Point (13, 13);
			this.listBox1.Name = "listBox1";
			this.listBox1.Size = new System.Drawing.Size (328, 368);
			this.listBox1.TabIndex = 0;
			//
			// startCheckBox
			//
			this.startCheckBox.Anchor = ((System.Windows.Forms.AnchorStyles)
				((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
			this.startCheckBox.Appearance = System.Windows.Forms.Appearance.Button;
			this.startCheckBox.Location = new System.Drawing.Point (347, 12);
			this.startCheckBox.Name = "startCheckBox";
			this.startCheckBox.Size = new System.Drawing.Size (75, 24);
			this.startCheckBox.TabIndex = 3;
			this.startCheckBox.Text = "&Start";
			this.startCheckBox.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
			this.startCheckBox.UseVisualStyleBackColor = true;
			this.startCheckBox.CheckedChanged += new System.EventHandler (this.onStartChanged);
			// 
			// Form1
			// 
			this.AutoScaleDimensions = new System.Drawing.SizeF (6f, 13f);
			this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
			this.ClientSize = new System.Drawing.Size (434, 391);
			this.Controls.Add (this.startCheckBox);
			this.Controls.Add (this.listBox1);
			this.Name = "Form1";
			this.Text = "Form1";
			this.ResumeLayout (false);
		}
		public bool InitializeReceiver ()
		{
			if (_socket != null) {
				StopReceiver ();
			}
			try {
				// create an IP/UDP socket
				_socket = new Socket (AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
 
			} catch (Exception ex) {
				listBox1.Items.Add ("SNMP trap receiver socket initialization failed with error: " + ex.Message);
				// there is no need to close the socket because it was never correctly created
				_socket = null;
			}
			if (_socket == null)
				return false;
			try {
				// prepare to "bind" the socket to the local port number
				// binding notifies the operating system that application 
				// wishes to receive data sent to the specified port number
 
				// prepare EndPoint that will bind the application to all available 
				//IP addresses and port 162 (snmp-trap)
				EndPoint localEP = new IPEndPoint (IPAddress.Any, 162);
				// bind socket
				_socket.Bind (localEP);
			} catch (Exception ex) {
				listBox1.Items.Add ("SNMP trap receiver initialization failed with error: " + ex.Message);
				_socket.Close ();
				_socket = null;
			}
			if (_socket == null)
				return false;
 
			if (!RegisterReceiveOperation ())
				return false;
 
			return true;
		}
		public void StopReceiver ()
		{
			if (_socket != null) {
				_socket.Close ();
				_socket = null;
			}
		}
		public bool RegisterReceiveOperation ()
		{
			if (_socket == null)
				return false;
			// socket has been closed
			try {
				_peerIP = new IPEndPoint (IPAddress.Any, 0);
				// receive from anybody
				EndPoint ep = (EndPoint)_peerIP;
				_inbuffer = new byte[64 * 1024];
				// nice and big receive buffer
				_socket.BeginReceiveFrom (_inbuffer, 0, 64 * 1024, 
					SocketFlags.None, ref ep, new AsyncCallback (ReceiveCallback), _socket);
			} catch (Exception ex) {
				listBox1.Items.Add ("Registering receive operation failed with message: " + ex.Message);
				_socket.Close ();
				_socket = null;
			}
			if (_socket == null)
				return false;
			return true;
		}
		private void ReceiveCallback (IAsyncResult result)
		{
			// get a reference to the socket. This is handy if socket has been closed elsewhere in the class
			Socket sock = (Socket)result.AsyncState;
 
			_peerIP = new IPEndPoint (IPAddress.Any, 0);
 
			// variable to store received data length
			int inlen;
 
			try {
				EndPoint ep = (EndPoint)_peerIP;
				inlen = sock.EndReceiveFrom (result, ref ep);
				_peerIP = (IPEndPoint)ep;
			} catch (Exception ex) {
				// only post messages if class socket reference is not null
				// in all other cases, user has terminated the socket
				if (_socket != null) {
					PostAsyncMessage ("Receive operation failed with message: " + ex.Message);
				}
				inlen = -1;
			}
			// if socket has been closed, ignore received data and return
			if (_socket == null)
				return;
			// check that received data is long enough
			if (inlen <= 0) {
				// request next packet
				RegisterReceiveOperation ();
				return;
			}
			int packetVersion = SnmpPacket.GetProtocolVersion (_inbuffer, inlen);
			if (packetVersion == (int)SnmpVersion.Ver1) {
				SnmpV1TrapPacket pkt = new SnmpV1TrapPacket ();
				try {
					pkt.decode (_inbuffer, inlen);
				} catch (Exception ex) {
					PostAsyncMessage ("Error parsing SNMPv1 Trap: " + ex.Message);
					pkt = null;
				}
				if (pkt != null) {
					PostAsyncMessage (String.Format ("** SNMPv1 TRAP from {0}", _peerIP.ToString ()));
					PostAsyncMessage (
						String.Format ("*** community {0} generic id: {1} specific id: {2}", 
							pkt.Community, pkt.Pdu.Generic, pkt.Pdu.Specific)
					);
					PostAsyncMessage (String.Format ("*** PDU count: {0}", pkt.Pdu.VbCount));
					foreach (Vb vb in pkt.Pdu.VbList) {
						PostAsyncMessage (
							String.Format ("**** Vb oid: {0} type: {1} value: {2}", 
								vb.Oid.ToString (), SnmpConstants.GetTypeName (vb.Value.Type), vb.Value.ToString ())
						);
					}
					PostAsyncMessage ("** End of SNMPv1 TRAP");
				}
			} else if (packetVersion == (int)SnmpVersion.Ver2) {
				SnmpV2Packet pkt = new SnmpV2Packet ();
				try {
					pkt.decode (_inbuffer, inlen);
				} catch (Exception ex) {
					PostAsyncMessage ("Error parsing SNMPv1 Trap: " + ex.Message);
					pkt = null;
				}
				if (pkt != null) {
					if (pkt.Pdu.Type == PduType.V2Trap) {
						PostAsyncMessage (String.Format ("** SNMPv2 TRAP from {0}", _peerIP.ToString ()));
					} else if (pkt.Pdu.Type == PduType.Inform) {
						PostAsyncMessage (String.Format ("** SNMPv2 INFORM from {0}", _peerIP.ToString ()));
					} else {
						PostAsyncMessage (String.Format ("Invalid SNMPv2 packet from {0}", _peerIP.ToString ()));
						pkt = null;
					}
					if (pkt != null) {
						PostAsyncMessage (
							String.Format ("*** community {0} sysUpTime: {1} trapObjectID: {2}", 
								pkt.Community, pkt.Pdu.TrapSysUpTime.ToString (), pkt.Pdu.TrapObjectID.ToString ())
						);
						PostAsyncMessage (String.Format ("*** PDU count: {0}", pkt.Pdu.VbCount));
						foreach (Vb vb in pkt.Pdu.VbList)
						{
							PostAsyncMessage (
								String.Format ("**** Vb oid: {0} type: {1} value: {2}", 
									vb.Oid.ToString (), SnmpConstants.GetTypeName (vb.Value.Type), vb.Value.ToString ())
							);
						}
						if (pkt.Pdu.Type == PduType.V2Trap)
							PostAsyncMessage ("** End of SNMPv2 TRAP");
						else {
							PostAsyncMessage ("** End of SNMPv2 INFORM");
 
							// send ACK back to the INFORM sender
							SnmpV2Packet response = pkt.BuildInformResponse ();
							byte[] buf = response.encode ();
							_socket.SendTo (buf, (EndPoint)_peerIP);
						}
					}
				}
			}
			RegisterReceiveOperation ();
		}
		protected delegate void PostAsyncMessageDelegate (string msg);
		protected void PostAsyncMessage (string msg)
		{
			if (InvokeRequired)
				Invoke (new PostAsyncMessageDelegate (PostAsyncMessage), new object[] { msg });
			else
				listBox1.Items.Add (msg);
		}
 
		private void onStartChanged (object sender, EventArgs e)
		{
			if (startCheckBox.Checked) {
				if (!InitializeReceiver ()) {
					// unable to start TRAP receiver
					startCheckBox.Checked = false;
					return;
				} else {
					startCheckBox.Text = "S&top";
				}
			} else {
				StopReceiver ();
				startCheckBox.Text = "&Start";
			}
		}
	}
}

Imports System
Imports System.Windows.Forms
Imports System.Net
Imports System.Net.Sockets
Imports SnmpSharpNet
 
Public Class Form1
    Inherits Form
    Dim _socket As Socket
    Dim _inbuffer() As Byte
    Dim _peerIP As IPEndPoint
    Dim listBox1 As System.Windows.Forms.ListBox
    Dim WithEvents startCheckBox As System.Windows.Forms.CheckBox
 
    Public Sub New()
 
        System.Diagnostics.Debug.WriteLine("OnLoad event")
 
        _socket = Nothing
 
        listBox1 = New System.Windows.Forms.ListBox()
        startCheckBox = New System.Windows.Forms.CheckBox()
        SuspendLayout()
        '
        ' listBox1
        '
        listBox1.Parent = Me
        listBox1.Anchor = ((((System.Windows.Forms.AnchorStyles.Top Or _
                              System.Windows.Forms.AnchorStyles.Bottom) Or _
                              System.Windows.Forms.AnchorStyles.Left) Or _
                              System.Windows.Forms.AnchorStyles.Right))
        listBox1.FormattingEnabled = True
        listBox1.Location = New System.Drawing.Point(13, 13)
        listBox1.Name = "listBox1"
        listBox1.Size = New System.Drawing.Size(328, 368)
        listBox1.TabIndex = 0
        '
        ' startCheckBox
        '
        startCheckBox.Parent = Me
        startCheckBox.Anchor = (System.Windows.Forms.AnchorStyles.Top Or _
                                System.Windows.Forms.AnchorStyles.Right)
        startCheckBox.Appearance = System.Windows.Forms.Appearance.Button
        startCheckBox.Location = New System.Drawing.Point(347, 12)
        startCheckBox.Name = "startCheckBox"
        startCheckBox.Size = New System.Drawing.Size(75, 24)
        startCheckBox.TabIndex = 3
        startCheckBox.Text = "&Start"
        startCheckBox.TextAlign = System.Drawing.ContentAlignment.MiddleCenter
        startCheckBox.UseVisualStyleBackColor = True
        ' 
        ' Form1
        ' 
        AutoScaleDimensions = New System.Drawing.SizeF(6.0F, 13.0F)
        AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
        ClientSize = New System.Drawing.Size(434, 391)
        Me.Controls.Add(startCheckBox)
        Me.Controls.Add(listBox1)
        Name = "Form1"
        Text = "Form1"
        ResumeLayout(False)
    End Sub
 
    Public Function InitializeReceiver() As Boolean
        If _socket IsNot Nothing Then
            StopReceiver()
        End If
        Try
            _socket = New Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp)
        Catch ex As Exception
            listBox1.Items.Add("SNMP trap receiver socket initialization failed with error: " & ex.Message)
            ' there is no need to close the socket because it was never correctly created
            _socket = Nothing
            Return False
        End Try
        Try
            Dim ep As EndPoint = New IPEndPoint(System.Net.IPAddress.Any, 162)
            _socket.Bind(ep)
        Catch ex As Exception
            listBox1.Items.Add("SNMP trap receiver initialization failed with error: " & ex.Message)
            _socket.Close()
            _socket = Nothing
            Return False
        End Try
        If RegisterReceiveOperation() = False Then
            Return False
        End If
        Return True
    End Function
 
    Public Sub StopReceiver()
        If _socket IsNot Nothing Then
            _socket.Close()
            _socket = Nothing
        End If
    End Sub
 
    Public Function RegisterReceiveOperation() As Boolean
        If _socket Is Nothing Then
            Return False
        End If
        Try
            _peerIP = New IPEndPoint(System.Net.IPAddress.Any, 0) ' receive from anybody
            _inbuffer = New [Byte](64 * 1024) {} ' nice and big receive buffer
            _socket.BeginReceiveFrom(_inbuffer, 0, _inbuffer.Length, _
                                     System.Net.Sockets.SocketFlags.None, _
                                     _peerIP, New AsyncCallback(AddressOf ReceiveCallback), _socket)
        Catch ex As Exception
            listBox1.Items.Add("Registering receive operation failed with message: " & ex.Message)
            _socket.Close()
            _socket = Nothing
            Return False
        End Try
        Return True
    End Function
 
    Public Sub ReceiveCallback(ByVal result As IAsyncResult)
        Dim sock As Socket = result.AsyncState
        Dim inlen As Integer
        _peerIP = New IPEndPoint(System.Net.IPAddress.Any, 0)
        Try
            inlen = sock.EndReceiveFrom(result, _peerIP)
        Catch ex As Exception
            ' only post messages if class socket reference is not null
            ' in all other cases, user has terminated the socket
            If _socket IsNot Nothing Then
                PostAsyncMessage("Receive operation failed with message: " & ex.Message)
            End If
            inlen = -1
        End Try
        ' if socket has been closed, don't process received data
        If _socket IsNot Nothing Then
            ' check that received data is long enough
            If inlen > 0 Then
                Dim packetVersion As Integer = SnmpPacket.GetProtocolVersion(_inbuffer, inlen)
                If packetVersion = SnmpVersion.Ver1 Then
                    Dim pkt As SnmpV1TrapPacket = New SnmpV1TrapPacket
                    Try
                        pkt.decode(_inbuffer, inlen)
                    Catch ex As Exception
                        PostAsyncMessage("Error parsing SNMPv1 Trap: " + ex.Message)
                        pkt = Nothing
                    End Try
                    If pkt IsNot Nothing Then
 
                        PostAsyncMessage(String.Format("** SNMPv1 TRAP from {0}", _peerIP.ToString()))
                        PostAsyncMessage(String.Format("*** community {0} generic id: {1} specific id: {2}", _
                                                       pkt.Community, pkt.Pdu.Generic, pkt.Pdu.Specific))
                        PostAsyncMessage(String.Format("*** PDU count: {0}", pkt.Pdu.VbCount))
                        Dim vb As Vb
                        For Each vb In pkt.Pdu.VbList
                            PostAsyncMessage(String.Format("**** Vb oid: {0} type: {1} value: {2}", _
                                vb.Oid.ToString(), SnmpConstants.GetTypeName(vb.Value.Type), _
                                vb.Value.ToString()))
                        Next
                        PostAsyncMessage("** End of SNMPv1 TRAP")
                    End If
                ElseIf packetVersion = SnmpVersion.Ver2 Then
                    Dim pkt As SnmpV2Packet = New SnmpV2Packet
                    Try
                        pkt.decode(_inbuffer, inlen)
                    Catch ex As Exception
                        pkt = Nothing
                    End Try
                    If pkt.Pdu.Type = PduType.V2Trap Then
                        PostAsyncMessage(String.Format("** SNMPv2 TRAP from {0}", _peerIP.ToString()))
                    ElseIf pkt.Pdu.Type = PduType.Inform Then
                        PostAsyncMessage(String.Format("** SNMPv2 INFORM from {0}", _peerIP.ToString()))
                    Else
                        PostAsyncMessage(String.Format("Invalid SNMPv2 packet from {0}", _peerIP.ToString()))
                        pkt = Nothing
                    End If
                    If pkt IsNot Nothing Then
                        PostAsyncMessage(String.Format("*** community {0} sysUpTime: {1} trapObjectID: {2}", _
                         pkt.Community, pkt.Pdu.TrapSysUpTime.ToString(), pkt.Pdu.TrapObjectID.ToString()))
                        PostAsyncMessage(String.Format("*** PDU count: {0}", pkt.Pdu.VbCount))
                        Dim vb As Vb
                        For Each vb In pkt.Pdu.VbList
                            PostAsyncMessage(String.Format("**** Vb oid: {0} type: {1} value: {2}", _
                             vb.Oid.ToString(), SnmpConstants.GetTypeName(vb.Value.Type), vb.Value.ToString()))
                        Next
                        If pkt.Pdu.Type = PduType.V2Trap Then
                            PostAsyncMessage("** End of SNMPv2 TRAP")
                        Else
                            PostAsyncMessage("** End of SNMPv2 INFORM")
                            ' send ACK back to the INFORM sender
                            Dim response As SnmpV2Packet = pkt.BuildInformResponse()
                            Dim buf() As Byte = response.encode()
                            _socket.SendTo(buf, _peerIP)
                        End If
                    End If
                End If
                RegisterReceiveOperation()
            End If
        End If
    End Sub
 
    Protected Delegate Sub PostAsyncMessageDelegate(ByVal msg As String)
 
    Protected Sub PostAsyncMessage(ByVal msg As String)
        If InvokeRequired Then
            Dim param() As Object
            param = New Object() {msg}
            Invoke(New PostAsyncMessageDelegate(AddressOf PostAsyncMessage), param)
        Else
            listBox1.Items.Add(msg)
        End If
    End Sub
 
    Private Sub OnStartChanged(ByVal sender As Object, ByVal e As EventArgs) _
        Handles startCheckBox.CheckedChanged
        If startCheckBox.Checked Then
            If Not InitializeReceiver() Then
                startCheckBox.Checked = False
            Else
                startCheckBox.Text = "S&top"
            End If
        Else
            StopReceiver()
            startCheckBox.Text = "&Start"
        End If
    End Sub
End Class

SnmpV1Packet packet = new SnmpV1Packet();
// Set the community name 
packet.Community.Set("public");
// Set the Pdu type 
packet.Pdu.Type = PduType.Get;
// Set request id 
packet.Pdu.RequestID = 100;
// Add an Oid for the SNMP-Get operation 
packet.Pdu.VbList.Add(".1.3.6.1.2.1.1.1.0");

 
// Set the Pdu type 
packet.Pdu.Type = PduType.Set;
// Add an Oid and Value for the SNMP-Set operation 
packet.Pdu.VbList.Add(new Oid(".1.3.6.1.2.1.1.1.0"), new OctetString("New sysDescr.0 value"));

byte[] outBuffer = packet.encode();

SnmpV1Packet result = new SnmpV1Packet();
result.decode(inBuffer, inLength);

packet.Reset();
packet.decode(inBuffer, inLength);

SnmpV2Packet packet = new SnmpV2Packet();
// Set the community name
packet.Community.Set("public");
// Set the Pdu type
packet.Pdu.Type = PduType.Get;
// Set request id
packet.Pdu.RequestID = 100;
// Add an Oid for the SNMP-Get operation
packet.Pdu.VbList.Add(".1.3.6.1.2.1.1.1.0");

// Set the Pdu type
packet.Pdu.Type = PduType.Set;
// Add an Oid and Value for the SNMP-Set operation
packet.Pdu.VbList.Add(new Oid(".1.3.6.1.2.1.1.1.0"), new OctetString("New sysDescr.0 value"));

byte[] outBuffer = packet.encode();

SnmpV2Packet result = new SnmpV2Packet();
result.decode(inBuffer, inLength);

packet.Reset();
packet.decode(inBuffer, inLength);

SnmpV2Packet packet = new SnmpV2Packet();
// Decode received packet
packet.decode(inBuffer, inLength);
// Make sure it is a V2Trap
if( packet.Pdu.Type == PduType.V2Trap )
{
	// Process information in the packet
	Console.WriteLine("Received trap {0} at agent upTime {1}", 
	             packet.Pdu.TrapObjectID.ToString(), packet.Pdu.TrapSysUpTime.ToString());
	foreach( Vb v in packet.Pdu.VbList ) {
		Console.WriteLine("\t{0}: {1} {2}", 
		             v.Oid.ToString(), SnmpConstants.GetTypeName(v.Value.Type), v.Value.ToString());
	}
}

// Set the Pdu type
packet.Pdu.Type = PduType.GetBulk;
// Add Oids to the request
packet.Pdu.VbList.Add(".1.3.6.1.2.1.1.3"); // sysUpTime
packet.Pdu.VbList.Add(".1.3.6.1.2.1.2.2.1.2"); // ifDescr
// Get 1 value for the first Oid, that will be sysUpTime (.1.3.6.1.2.1.1.3.0)
packet.Pdu.NonRepeaters = 1;
// Retrieve up to 50 ifDescr interface description values in a single request
packet.Pdu.MaxRepetitions = 50;

// Construct the packet class.
SnmpV2Packet packet = new SnmpV2Packet();
// Decode received information.
packet.decode(inBuffer, inLength);
// Verify we received an Inform packet.
if( packet.Pdu.Type == PduType.Inform )
{
	// Construct appropriate response to the Inform.
	SnmpV2Packet response = packet.BuildInformResponse();
	// BER encode response packet.
	byte[] outBuffer = response.encode();
	// Send response back to the Inform sender.
	mysocket.SendTo(outBuffer,new IPEndPoint(someip, someport));
}

// Create discovery packet using SnmpV3Packet.DiscoveryRequest() static method
SnmpV3Packet discovery = SnmpV3Packet.DiscoveryRequest();
// BER encode discovery packet
byte[] outBuffer = discovery.encode();
// Send discovery packet to the agent
mysocket.SendTo(outBuffer, new IPEndPoint(agentIP, agentPort));

// Decode received packet
discovery.decode(inBuffer, inLength);
// Make sure received packet is SNMP v3 Report
if( discovery.Version != SnmpVersion.Ver3 )
{
	return; // Invalid SNMP version
}
if( discovery.Pdu.Type != PduType.Report )
{
	return; // Invalid response. We have to get a Report
}
if( ! discovery.Pdu.VbList[0].Oid.Equals(SnmpConstants.usmStatsUnknownEngineIDs) )
{
	return; // Wrong kind of error message sent by agent
}
// Success !!

// Authoritative Engine ID
OctetString engineID = (OctetString)discovery.USM.EngineId.Clone();
// Authoritative Engine Boots
Int32 engineBoots = discovery.USM.EngineBoots;
// Authoritative Engine Time
Int32 engineTime  = discovery.USM.EngineTime;
// Timestamp when discovery process was completed
DateTime discoveryTime = DateTime.Now;
// Maximum message size agent can process
Int32 maxMessageSize = discovery.MaxMessageSize;

// Request packet class
SnmpV3Packet request = new SnmpV3Packet();
// Set security model to NoAuthNoPriv with SecurityName "milan"
request.NoAuthNoPriv(ASCIIEncoding.UTF8.GetBytes("milan"));
// Set authoritative engine ID retrieved during discovery
request.SetEngineId(engineID);
// Set timeliness values retrieved during discovery
request.SetEngineTime(engineBoots, engineTime);
// Set maximum message size
request.MaxMessageSize = maxMessageSize;
// Set Pdu type to Get
request.ScopedPdu.Type = PduType.Get;
// Add Oid to query to the VbList
request.ScopedPdu.VbList.Add(".1.3.6.1.2.1.1.1.0");
// Encode request
outBuffer = request.encode();
 
// Now you are ready to send the request to the agent

request.decode(inBuffer, inLength);

// Create a response packet class
SnmpV3Packet response = new SnmpV3Packet();
// Decode response
response.decode(inBuffer, inLength);
 
// Process response
Console.WriteLine("Reply received to message id {0} request id {1}", 
             response.MessageId, response.Pdu.RequestId);
Console.WriteLine("\t{0}: {1} {2}", response.ScopedPdu.VbList[0].Oid.ToString(),
  SnmpConstants.GetTypeName(response.ScopedPdu.VbList[0].Value.Type),
  response.ScopedPdu.VbList[0].Value.ToString());

request.authNoPriv(ASCIIEncoding.UTF8.GetBytes("milan"),
	ASCIIEncoding.UTF8.GetBytes("myAuthSecret"), AuthenticationDigests.MD5);

// Create a response packet class
SnmpV3Packet response = new SnmpV3Packet();
// Set authentication parameters to use with the incoming packet
response.authNoPriv(ASCIIEncoding.UTF8.GetBytes("milan"),
	ASCIIEncoding.UTF8.GetBytes("myAuthSecret"), AuthenticationDigests.MD5);
// Decode response
response.decode(inBuffer, inLength);

request.authPriv(ASCIIEncoding.UTF8.GetBytes("milan"),
	ASCIIEncoding.UTF8.GetBytes("myAuthSecret"), AuthenticationDigests.MD5,
	ASCIIEncoding.UTF8.GetBytes("myPrivSecret"), PrivacyProtocols.DES);

// Create a response packet class
SnmpV3Packet response = new SnmpV3Packet();
// Set authentication and privacy parameters to use with the incoming packet
request.authPriv(ASCIIEncoding.UTF8.GetBytes("milan"),
	ASCIIEncoding.UTF8.GetBytes("myAuthSecret"), AuthenticationDigests.MD5,
	ASCIIEncoding.UTF8.GetBytes("myPrivSecret"), PrivacyProtocols.DES);
// Decode response
response.decode(inBuffer, inLength);

public class USMPeer
{
	protected OctetString _engineId;
	protected OctetString _securityName;
	protected AuthenticationDigests _authenticationType;
	protected PrivacyProtocols _privacyType;
	protected OctetString _authenticationSecret;
	protected OctetString _privacySecret;
	public USMPeer()
	{
		_engineId = new OctetString();
		_securityName = new OctetString();
		_authenticationType = AuthenticationDigests.None;
		_authenticationSecret = new OctetString();
		_privacyType = PrivacyProtocols.None;
		_privacySecret = new OctetString();
	}
	public USMPeer(OctetString engineId, OctetString securityName)
		: this()
	{
		_engineId.Set(engineId);
		_securityName.Set(securityName);
	}
	public USMPeer(OctetString engineId, OctetString securityName,
		AuthenticationDigests authDigest, OctetString authSecret)
		: this(engineId, securityName)
	{
		_authenticationType = authDigest;
		_authenticationSecret.Set(authSecret);
	}
	public USMPeer(OctetString engineId, OctetString securityName,
		AuthenticationDigests authDigest, OctetString authSecret, 
		PrivacyProtocols privType, OctetString privSecret)
		: this(engineId, securityName, authDigest, authSecret)
	{
		_privacyType = privType;
		_privacySecret.Set(privSecret);
	}
	public bool IsMatch(OctetString engineId, OctetString securityname)
	{
		if (_engineId.Equals(engineId) && _securityName.Equals(securityname))
			return true;
		return false;
	}
	public bool IsMatch(OctetString securityname)
	{
		if (_engineId.Length <= 0 && _securityName.Equals(securityname))
			return true;
		return false;
	}
	public SnmpSharpNet.OctetString EngineId
	{
		get { return _engineId; }
	}
	public SnmpSharpNet.OctetString SecurityName
	{
		get { return _securityName; }
	}
	public SnmpSharpNet.AuthenticationDigests AuthenticationType
	{
		get { return _authenticationType; }
		set { _authenticationType = value; }
	}
	public SnmpSharpNet.PrivacyProtocols PrivacyType
	{
		get { return _privacyType; }
		set { _privacyType = value; }
	}
	public SnmpSharpNet.OctetString AuthenticationSecret
	{
		get { return _authenticationSecret; }
	}
	public SnmpSharpNet.OctetString PrivacySecret
	{
		get { return _privacySecret; }
	}
}

// Collection to hold agent information
public List<USMPeer> _usmPeers =  new List<USMPeer>();
 
// noAuthNoPriv agent with security name test
_usmPeers.Add(new USMPeer(null, new OctetString("test")));
 
// authNoPriv agent using MD5 authentication with security name testMD5 and
//  authentication secret md5authNoPriv
_usmPeers.Add(new USMPeer(null, new OctetString("testMD5"), AuthenticationDigests.MD5,
	new OctetString("md5authNoPriv")));
 
// authNoPriv agent using SHA-1 authentication with security name testSHA1 and
//  authentication secret sha1authNoPriv
_usmPeers.Add(new USMPeer(null, new OctetString("testSHA1"), AuthenticationDigests.SHA1, 
	new OctetString("sha1authNoPriv")));
 
// authPriv agent using MD5 authentication and DES privacy with security name testDESMD5,
//  authentication secret md5desauthPriv and privacy secret md5desAuthPriv
_usmPeers.Add(new USMPeer(null, new OctetString("testDESMD5"), AuthenticationDigests.MD5, 
	new OctetString("md5desauthPriv"), PrivacyProtocols.DES, new OctetString("md5desAuthPriv")));
 
// authPriv agent using SHA-1 authentication and DES privacy with security name testDESMD5,
//  authentication secret sha1desauthPriv and privacy secret sha1desauthPriv
_usmPeers.Add(new USMPeer(null, new OctetString("testDESMD5"), AuthenticationDigests.SHA1, 
	new OctetString("sha1desauthPriv"), PrivacyProtocols.DES, new OctetString("sha1desAuthPriv")));
 
// authPriv agent using MD5 authentication and AES-128 privacy with security name testAESMD5,
//  authentication secret md5aesAuthPriv and privacy secret md5aesAuthPriv
_usmPeers.Add(new USMPeer(null, new OctetString("testAESMD5"), AuthenticationDigests.MD5, 
	new OctetString("md5aesauthPriv"), PrivacyProtocols.AES128, new OctetString("md5aesAuthPriv")));
 
// authPriv agent using SHA-1 authentication and AES-128 privacy with security name testAESSHA1,
//  authentication secret sha1aesAuthPriv and privacy secret sha1aesAuthPriv
_usmPeers.Add(new USMPeer(null, new OctetString("testAESSHA1"), AuthenticationDigests.SHA1, 
	new OctetString("sha1aesauthPriv"), PrivacyProtocols.AES128, new OctetString("sha1aesAuthPriv")));

// noAuthNoPriv agent with security name test tied to specific engine id
_usmPeers.Add(new USMPeer(
     new OctetString(new byte[] { 0x04,0x0D,0x80,0x00,0x1F,0x88,0x80,0x9A,0x4A,0x00,0x00,0x2A,0xC0,0x9A,0x49}, 
     new OctetString("test")));

public USMPeer FindPeer(OctetString engineId, OctetString securityName)
{
	// look for specific entires first trying to match both engineId and securityName
	if( engineId != null )
	{
		foreach (USMPeer peer in _usmPeers)
		{
			if (peer.IsMatch(engineId, securityName))
				return peer;
		}
	}
	// no specific entries found. Look for entries not assigned to specific engine id
	foreach (USMPeer peer in _usmPeers)
	{
		if (peer.IsMatch(securityName))
			return peer;
	}
 
	return null; // match not found
}

// We'll need a byte buffer to store incoming data
byte[] inbuffer = new byte[32 * 1024];
// End point details of the host we received packet(s) from
EndPoing peer = (EndPoint)new IPEndPoint(IPAddress.Any, 0);
// Create a IP/UDP socket
Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
// Bind the socket to the standard snmptrapd port = udp/162
socket.Bind((EndPoint)new IPEndPoint(IPAddress.Any, 162));
// Wait for a packet
int inlen = _socket.ReceiveFrom(inbuffer, SocketFlags.None, ref peer);
// Make sure we received some data instead of an empty packet.
if( inlen <= 0 )
{
	Console.WriteLine("Received an invalid SNMP packet length 0 Bytes.");
	socket.Close();
	return;
}

// Make sure received packet is SNMP version 3
int ver = SnmpPacket.GetProtocolVersion(_inbuffer, inlen);
 
if( ver != (int)SnmpVersion.Ver3 )
{
	Console.WriteLine("Received packet is not SNMP version 3.");
	socket.Close();
	return;
}
 
SnmpV3Packet packet = new SnmpV3Packet();
 
// Do partial parse to get enough information to set authentication and privacy info
UserSecurityModel usm = packet.GetUSM(_inbuffer, inlen);
 
// Check this is a valid packet
 
// Valid engine id has to be set in the packet.
if( usm.EngineId.Length <= 0 )
{
	Console.WriteLine("Invalid packet. Authoritative engine id is not set.");
	_socket.Close();
	return;
}
// Security name has to be set in a valid packet
if( usm.SecurityName.Length <= 0 )
{
	Console.WriteLine("Invalid packet. Security name is not set.");
	_socket.Close();
	return;
}

// Locate the peer entry
USMPeer peer = FindPeer(usm.EngineId, usm.SecurityName);
if (peer == null)
{
	// Couldn't find the peer so abort further processing...
	Console.WriteLine("SNMP packet from unknown peer.");
	socket.Close();
	return;
}
 
// Set authentication type for the peer
packet.USM.Authentication = peer.AuthenticationType;
// Set privacy type from the peer
packet.USM.Privacy = peer.PrivacyType;
// If privacy is used, set the privacy secret in the packet class.
if( peer.PrivacyType != PrivacyProtocols.None )
	packet.USM.PrivacySecret.Set(peer.PrivacySecret);
// If authentication is used, set the authentication secret in the packet class.
if( peer.AuthenticationType != AuthenticationDigests.None )
	packet.USM.AuthenticationSecret.Set(peer.AuthenticationSecret);
// Decode the packet.
packet.decode(_inbuffer, inlen);

if (packet.Pdu.Type != PduType.V2Trap)
{
	Console.WriteLine("Invalid SNMP version 3 packet type received.");
}

Console.WriteLine("trapSysUpTime.0: {0}", packet.Pdu.TrapSysUpTime.ToString());
Console.WriteLine("trapObjectID.0 : {0}", packet.Pdu.TrapObjectID.ToString());

foreach( Vb v in packet.Pdu.VbList )
{
	Console.WriteLine("{0}: {1}", v.Oid.ToString(), v.Value.ToString());
}

// Define an engine id
OctetString engineId = 
     new OctetString(new byte[] { 0x00, 0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01, 0x00 });
// Store time value at the time your application started
DateTime engineTime = DateTime.Now;

SnmpV3Packet packet = new SnmpV3Packet();
// Have a look inside the packet for security information
UserSecurityModel usm = packet.GetUSM(inbuffer, inlen);
// It's a discovery request if engine id or security name are empty values
if (usm.EngineId.Length <= 0 || usm.SecurityName.Length <= 0)
{
	// Calculate application uptime
	int dateTime = Convert.ToInt32(Math.Floor(DateTime.Now.Subtract(engineTime).TotalMinutes));
	// Use SnmpV3Packet.DiscoveryResponse() method to create a discovery operation reply packet
	SnmpV3Packet discoveryResponse = 
	    SnmpV3Packet.DiscoveryResponse(packet.MessageId, 0, _engineId, 0, dateTime, 1);
	// BER encode the reply packet
	byte[] outPacket = discoveryResponse.encode();
	// and send the encoded reply back to the originator of the request.
	socket.SendTo(outPacket, ep);
}

// We now received another packet after discovery process was completed...
 
SnmpV3Packet packet = new SnmpV3Packet();
// Have a look inside the packet for security information
UserSecurityModel usm = packet.GetUSM(inbuffer, inlen);
// Find SNMP peer (remember, engineId value is your application sent value
USMPeer peer = FindPeer(usm.EngineId, usm.SecurityName);
if (peer == null)
{
	// Couldn't find the peer so abort further processing...
	Console.WriteLine("SNMP packet from unknown peer.");
	socket.Close();
	return;
}
 
// Set authentication type for the peer
packet.USM.Authentication = peer.AuthenticationType;
// Set privacy type from the peer
packet.USM.Privacy = peer.PrivacyType;
// If privacy is used, set the privacy secret in the packet class.
if( peer.PrivacyType != PrivacyProtocols.None )
	packet.USM.PrivacySecret.Set(peer.PrivacySecret);
// If authentication is used, set the authentication secret in the packet class.
if( peer.AuthenticationType != AuthenticationDigests.None )
	packet.USM.AuthenticationSecret.Set(peer.AuthenticationSecret);
// Decode the packet.
packet.decode(_inbuffer, inlen);

SnmpV3Packet infResponse = SnmpV3Packet.BuildInformResponse(packet);
byte[] outPkt = infResponse.encode();
socket.SendTo(outPkt, ep);

UdpTarget target = new UdpTarget((IPAddress)SomeHostIP);
SecureAgentParameters param = new SecureAgentParameters();
if (!target.Discovery(param))
{
  Console.WriteLine("Discovery failed. Unable to continue...");
  target.Close();
  return;
}

param.SecurityName.Set("mySecureName");

// Construct a Protocol Data Unit (PDU)
Pdu pdu = new Pdu();
// Set the request type (default is GET)
pdu.Type = PduType.Get;
// Add variables you wish to query
pdu.VbList.Add("1.3.6.1.2.1.1.1.0");
// optional: make sure no authentication or privacy is configured in the 
// SecureAgentParameters class (see discovery section above)
param.Authentication = AuthenticationDigests.None;
param.Privacy = PrivacyProtocols.None;
// optional: make sure you request REPORT packet return on errors
param.Reportable = false;
// Make a request. Request can throw a number of errors so wrap it in try/catch
SnmpV3Packet result;
try {
  SnmpV3Packet result = (SnmpV3Packet)target.Request(pdu, param);
} catch( Exception ex ) {
  // deal with errors
  result = null;
}
if( result != null ) {
  // You have results to process here....
}

// Set the authentication digest
param.Authentication = AuthenticationDigests.MD5;
// Set the authentication password
param.AuthenticationSecret.Set("password");

// Set the authentication digest
param.Authentication = AuthenticationDigests.SHA1;
// Set the authentication password
param.AuthenticationSecret.Set("password");

// Set the privacy protocol
param.Privacy = PrivacyProtocols.DES;
// Set the privacy password
param.PrivacySecret.Set("CryptoPassword");

// Set the privacy protocol
param.Privacy = PrivacyProtocols.AES128;
// Set the privacy password
param.PrivacySecret.Set("CryptoPassword");

try {
  SnmpV3Packet result = (SnmpV3Packet)target.Request(pdu, param);
} catch( Exception ex ) {
  // deal with errors
  result = null;
}
if( result != null ) {
  if (result.Pdu.Type == PduType.Report)
  {
    // we've got an error
    Console.WriteLine("Report packet received.");
    string errstr = SNMPV3ReportError.TranslateError(pkt);
    Console.WriteLine("Error: {0}", errstr);
    target.Close();
    return;
  }
  if (result.Pdu.ErrorStatus != 0)
  {
    Console.WriteLine("SNMP target has returned error code {0} on index {1}.",
                      SnmpError.ErrorMessage(result.Pdu.ErrorStatus), 
                      result.Pdu.ErrorIndex);
    return;
  }
  // Process returned Oid/Variable pairs
  foreach( Vb v in result.Pdu.VbList ) {
    Console.WriteLine("{0}: {1} {2}", v.Key.ToString(), 
        SnmpConstants.GetTypeName(v.Value.Type), v.Value.ToString());
  }
}

TrapAgent agent = new TrapAgent();
 
// Variable Binding collection to send with the trap
VbCollection col = new VbCollection();
col.Add(new Oid("1.3.6.1.2.1.1.1.0"), new OctetString("Test string"));
col.Add(new Oid("1.3.6.1.2.1.1.2.0"), new Oid("1.3.6.1.9.1.1.0"));
col.Add(new Oid("1.3.6.1.2.1.1.3.0"), new TimeTicks(2324));
col.Add(new Oid("1.3.6.1.2.1.1.4.0"), new OctetString("Milan"));
 
// Send the trap to the localhost port 162
agent.SendV1Trap(new IpAddress("localhost"), 162, "public", 
                 new Oid("1.3.6.1.2.1.1.1.0"), new IpAddress("127.0.0.1"),
                 SnmpConstants.LinkUp, 0, 13432, col);

Imports SnmpSharpNet
 
Module Module1
    Sub Main()
        Dim host As String = "localhost"
        Dim community As String = "public"
        Dim agent As TrapAgent = New TrapAgent()
 
        Dim col As VbCollection = New VbCollection()
        col.Add(New Oid("1.3.6.1.2.1.1.1.0"), New OctetString("Test string"))
        col.Add(New Oid("1.3.6.1.2.1.1.2.0"), New Oid("1.3.6.1.9.1.1.0"))
        Dim timeTickVal As UInt32 = 2324
        col.Add(New Oid("1.3.6.1.2.1.1.3.0"), New TimeTicks(timeTickVal))
        col.Add(New Oid("1.3.6.1.2.1.1.4.0"), New OctetString("MyName"))
        agent.SendV1Trap(New IpAddress("localhost"), 162, "public", _
            New Oid("1.3.6.1.2.1.1.1.0"), New IpAddress("127.0.0.1"), _
            SnmpConstants.LinkUp, 0, 13432, col)
    End Sub
End Module

agent.SendV2Trap(new IpAddress("localhost"), 162, "public", 13433, 
                 new Oid(".1.3.6.1.6.3.1.1.5"), col);

agent.SendV2Trap(New IpAddress("localhost"), 162, "public", 13433, _
                 New Oid(".1.3.6.1.6.3.1.1.5"), col)

agent.SendV3Trap(new IpAddress("localhost"), 162, 
                 new byte[] { 0x00, 0x08, 0x02, 0x01, 0x20, 0x12, 0x14, 0xa0, 0xb1, 0xc2 },
                 1, 500, "mysecurityname", 13434, new Oid(".1.3.6.1.6.3.1.1.5"), col);

agent.SendV3Trap(New IpAddress("localhost"), 162, _
                 New Byte() {&H0, &H8, &H2, &H1, &H20, &H12, &H14, &HA0, &HB1, &HC2}, _
                 1, 500, "mysecurityname", 13434, New Oid(".1.3.6.1.6.3.1.1.5"), col)

agent.SendV3Trap(new IpAddress("localhost"), 162, 
                 new byte[] { 0x00, 0x08, 0x02, 0x01, 0x20, 0x12, 0x14, 0xa0, 0xb1, 0xc2 },
                 1, 501, "myauthenticationname", 13435, new Oid(".1.3.6.1.6.3.1.1.5"), col, 
                 AuthenticationDigests.MD5,ASCIIEncoding.UTF8.GetBytes("authpasswd"));

agent.SendV3Trap(New IpAddress("localhost"), 162, _
                 New Byte() {&H0, &H8, &H2, &H1, &H20, &H12, &H14, &HA0, &HB1, &HC2}, _
                 1, 501, "myauthenticationname", 13435, New Oid(".1.3.6.1.6.3.1.1.5"), col, _
                 AuthenticationDigests.MD5, _
                 System.Text.ASCIIEncoding.UTF8.GetBytes("authpasswd"))

agent.SendV3Trap(new IpAddress("localhost"), 162, 
                 new byte[] { 0x00, 0x08, 0x02, 0x01, 0x20, 0x12, 0x14, 0xa0, 0xb1, 0xc2 },
                 1, 501, "myauthenticationname", 13435, new Oid(".1.3.6.1.6.3.1.1.5"), col, 
                 AuthenticationDigests.MD5, ASCIIEncoding.UTF8.GetBytes("authpasswd"),
                 PrivacyProtocols.DES, ASCIIEncoding.UTF8.GetBytes("privpasswd"));

agent.SendV3Trap(New IpAddress("localhost"), 162, _
                         New Byte() {&H0, &H8, &H2, &H1, &H20, &H12, &H14, &HA0, &HB1, &HC2}, _
                         1, 501, "myauthenticationname", 13435, _
                         New Oid(".1.3.6.1.6.3.1.1.5"), col, _
                         AuthenticationDigests.MD5, _
                         System.Text.ASCIIEncoding.UTF8.GetBytes("authpasswd"), _
                         PrivacyProtocols.DES, _
                         System.Text.ASCIIEncoding.UTF8.GetBytes("privpasswd"))

SnmpV3Packet packet = new SnmpV3Packet();
// Set the security name
packet.NoAuthNoPriv(ASCIIEncoding.UTF8.GetBytes("mysecurityname"));
// Set your engine id
packet.USM.EngineId.Set(new byte[] { 0x00, 0x08, 0x02, 0x01, 0x10, 0x12, 0x14, 0xa0, 0xb1, 0xc2 });
// Engine id is also stored in the ScopedPdu so just duplicate it
packet.ScopedPdu.ContextEngineId.Set(packet.USM.EngineId);
// Set your engine boots (can be 0)
packet.USM.EngineBoots = 20;
// Set your engine time
packet.USM.EngineTime = 200;
// Set message reportable flag to false. You don't really want to receive errors
packet.MsgFlags.Reportable = false;
// Pdu type is V2TRAP
packet.Pdu.Type = PduType.V2Trap;
// Set the TRAP object ID value
packet.Pdu.TrapObjectID.Set(new int[] { 1, 3, 6, 1, 2, 1, 2, 2, 1, 0 });
// Set your system up time value (this has nothing to do with engineTime)
packet.Pdu.TrapSysUpTime.Value = 23456;
// Add variable bindings to the Pdu to further describe the TRAP
packet.Pdu.VbList.Add(new Oid(new int[] { 1, 3, 6, 1, 2, 1, 1, 1, 0 }), new OctetString("Test noAuthNoPriv"));
// Finally, encode into a byte buffer ready for sending
byte[] outBuffer = packet.encode();
// Send it to the manager
sock.SendTo(outBuffer,new IPEndPoint(IPAddress.Loopback, 162));

SnmpV3Packet packet = new SnmpV3Packet();
// Set security name and authentication parameters needed for a authNoPriv TRAP
packet.authNoPriv(ASCIIEncoding.UTF8.GetBytes("myauthenticationname"), 
	ASCIIEncoding.UTF8.GetBytes("authpasswd"), AuthenticationDigests.MD5);
// Set your engine id
packet.USM.EngineId.Set(new byte[] { 0x00, 0x08, 0x02, 0x01, 0x10, 0x12, 0x14, 0xa0, 0xb1, 0xc2 });
// Engine id is also stored in the ScopedPdu so just duplicate it
packet.ScopedPdu.ContextEngineId.Set(packet.USM.EngineId);
// Set your engine boots (can be 0)
packet.USM.EngineBoots = 20;
// Set your engine time
packet.USM.EngineTime = 200;
// Set message reportable flag to false. You don't really want to receive errors
packet.MsgFlags.Reportable = false;
// Pdu type is V2TRAP
packet.Pdu.Type = PduType.V2Trap;
// Set the TRAP object ID value
packet.Pdu.TrapObjectID.Set(new int[] { 1, 3, 6, 1, 2, 1, 2, 2, 1, 0 });
// Set your system up time value (this has nothing to do with engineTime)
packet.Pdu.TrapSysUpTime.Value = 23456;
// Add variable bindings to the Pdu to further describe the TRAP
packet.Pdu.VbList.Add(new Oid(new int[] { 1, 3, 6, 1, 2, 1, 1, 1, 0 }), new OctetString("Test noAuthNoPriv"));
// Finally, encode into a byte buffer ready for sending
byte[] outBuffer = packet.encode();
// Send it to the manager
sock.SendTo(outBuffer,new IPEndPoint(IPAddress.Loopback, 162));

SnmpV3Packet packet = new SnmpV3Packet();
// Set security name and authentication and privacy parameters needed for authPriv TRAP
packet.authPriv(ASCIIEncoding.UTF8.GetBytes("myauthprivname"), 
	ASCIIEncoding.UTF8.GetBytes("authpasswd"), AuthenticationDigests.MD5,
	ASCIIEncoding.UTF8.GetBytes("privpasswd"), PrivacyProtocols.DES);
// Set your engine id
packet.USM.EngineId.Set(new byte[] { 0x00, 0x08, 0x02, 0x01, 0x10, 0x12, 0x14, 0xa0, 0xb1, 0xc2 });
// Engine id is also stored in the ScopedPdu so just duplicate it
packet.ScopedPdu.ContextEngineId.Set(packet.USM.EngineId);
// Set your engine boots (can be 0)
packet.USM.EngineBoots = 20;
// Set your engine time
packet.USM.EngineTime = 200;
// Set message reportable flag to false. You don't really want to receive errors
packet.MsgFlags.Reportable = false;
// Pdu type is V2TRAP
packet.Pdu.Type = PduType.V2Trap;
// Set the TRAP object ID value
packet.Pdu.TrapObjectID.Set(new int[] { 1, 3, 6, 1, 2, 1, 2, 2, 1, 0 });
// Set your system up time value (this has nothing to do with engineTime)
packet.Pdu.TrapSysUpTime.Value = 23456;
// Add variable bindings to the Pdu to further describe the TRAP
packet.Pdu.VbList.Add(new Oid(new int[] { 1, 3, 6, 1, 2, 1, 1, 1, 0 }), new OctetString("Test authNoPriv"));
// Finally, encode into a byte buffer ready for sending
byte[] outBuffer = packet.encode();
// Send it to the manager
sock.SendTo(outBuffer,new IPEndPoint(IPAddress.Loopback, 162));

string host = "localhost";
string community = "public";
SimpleSnmp snmp = new SimpleSnmp(host, community);
 
if (!snmp.Valid)
{
	Console.WriteLine("SNMP agent host name/ip address is invalid.");
	return;
}
Dictionary<Oid,AsnType> result = snmp.Get(SnmpVersion.Ver1, 
                                          new string[] { ".1.3.6.1.2.1.1.1.0"} );
if (result == null)
{
	Console.WriteLine("No results received.");
	return;
}
 
foreach (KeyValuePair kvp in result)
{
	Console.WriteLine("{0}: {1} {2}", kvp.Key.ToString(), 
                          SnmpConstants.GetTypeName(kvp.Value.Type), 
                          kvp.Value.ToString());
}

Dictionary<Oid,AsnType> result = snmp.GetNext(SnmpVersion.Ver2, 
                                                    new string[] { 
                                                        ".1.3.6.1.2.1.1.1", 
                                                        ".1.3.6.1.2.1.1.2"
                                                    } );

Dictionary<Oid,AsnType> result = snmp.GetBulk(new string[] { ".1.3.6.1.2", ".1.3.6.1.3"} );

Dictionary<Oid,AsnType> result = snmp.Set(SnmpVersion.Ver2, 
                                                    new Vb[] { 
                                                    new Vb(new Oid(".1.3.6.1.2.1.1.1.0"), 
                                                           new OctetString("New sysDescr.0")
                                                    } );

Dictionary result = snmp.Walk(SnmpVersion.Ver2, ".1.3.6.1.2.1.1.1");

Imports System
Imports SnmpSharpNet
 
Module Module1
 
    Sub Main()
        Dim host As String = "localhost"
        Dim community As String = "public"
        Dim requestOid() As String
        Dim result As Dictionary(Of Oid, AsnType)
        requestOid = New String() {"1.3.6.1.2.1.1.1.0", "1.3.6.1.2.1.1.2.0"}
        Dim snmp As SimpleSnmp = New SimpleSnmp(host, community)
        If Not snmp.Valid Then
            Console.WriteLine("Invalid hostname/community.")
            Exit Sub
        End If
        result = snmp.Get(SnmpVersion.Ver1, requestOid)
        If result IsNot Nothing Then
            Dim kvp As KeyValuePair(Of Oid, AsnType)
            For Each kvp In result
                Console.WriteLine("{0}: ({1}) {2}", kvp.Key.ToString(), _
                                  SnmpConstants.GetTypeName(kvp.Value.Type), _
                                  kvp.Value.ToString())
            Next
        Else
            Console.WriteLine("No results received.")
        End If
    End Sub
 
End Module

Imports System
Imports SnmpSharpNet
 
Module Module1
 
    Sub Main()
        Dim host As String = "localhost"
        Dim community As String = "public"
        Dim requestOid() As String
        Dim result As Dictionary(Of Oid, AsnType)
        Dim rootOid As Oid = New Oid("1.3.6.1.2.1.1")
        Dim nextOid As Oid = rootOid
        Dim keepGoing As Boolean = True
        requestOid = New String() {rootOid.ToString()}
        Dim snmp As SimpleSnmp = New SimpleSnmp(host, community)
        If Not snmp.Valid Then
            Console.WriteLine("Invalid hostname/community.")
            Exit Sub
        End If
        While keepGoing
            result = snmp.GetNext(SnmpVersion.Ver1, New String() {nextOid.ToString()})
            If result IsNot Nothing Then
                Dim kvp As KeyValuePair(Of Oid, AsnType)
                For Each kvp In result
                    If rootOid.IsRootOf(kvp.Key) Then
                        Console.WriteLine("{0}: ({1}) {2}", kvp.Key.ToString(), _
                                              SnmpConstants.GetTypeName(kvp.Value.Type), _
                                              kvp.Value.ToString())
                        nextOid = kvp.Key
                    Else
                        keepGoing = False
                    End If
                Next
            Else
                Console.WriteLine("No results received.")
                keepGoing = False
            End If
        End While
    End Sub
 
End Module

Imports System
Imports SnmpSharpNet
 
Module Module1
 
    Sub Main()
        ' SNMP Agent hostname or IP address
        Dim host As String = "localhost"
        ' SNMP community name
        Dim community As String = "public"
        ' Dictionary to store values returned by GetBulk calls
        Dim result As Dictionary(Of Oid, AsnType)
        ' Root Oid for the request (ifTable.ifEntry.ifDescr in this example)
        Dim rootOid As Oid = New Oid("1.3.6.1.2.1.2.2.1.2")
        Dim nextOid As Oid = rootOid
        Dim keepGoing As Boolean = True
        ' Initialize SimpleSnmp class
        Dim snmp As SimpleSnmp = New SimpleSnmp(host, community)
        If Not snmp.Valid Then
            Console.WriteLine("Invalid hostname/community.")
            Exit Sub
        End If
        ' Set NonRepeaters and MaxRepetitions for the GetBulk request (optional)
        snmp.NonRepeaters = 0
        snmp.MaxRepetitions = 20
        While keepGoing
            ' Make a request
            result = snmp.GetBulk(New String() {nextOid.ToString()})
            ' Check SNMP agent returned valid results
            If result IsNot Nothing Then
                Dim kvp As KeyValuePair(Of Oid, AsnType)
                ' Loop through returned values
                For Each kvp In result
                    ' Check that returned Oid is part of the original root Oid
                    If rootOid.IsRootOf(kvp.Key) Then
                        Console.WriteLine("{0}: ({1}) {2}", kvp.Key.ToString(), _
                                              SnmpConstants.GetTypeName(kvp.Value.Type), _
                                              kvp.Value.ToString())
                        ' Store last valid Oid to use in additional GetBulk requests (if required)
                        nextOid = kvp.Key
                    Else
                        ' We found a value outside of the root Oid tree. Do not perform additional GetBulk ops
                        keepGoing = False
                    End If
                Next
            Else
                Console.WriteLine("No results received.")
                keepGoing = False
            End If
        End While
    End Sub
 
End Module

Imports System
Imports SnmpSharpNet
 
Module Module1
 
    Sub Main()
        Dim host As String = "localhost"
        Dim community As String = "public"
        Dim result As Dictionary(Of Oid, AsnType)
        Dim snmp As SimpleSnmp = New SimpleSnmp(host, community)
        If Not snmp.Valid Then
            Console.WriteLine("Invalid hostname/community.")
            Exit Sub
        End If
        result = snmp.Walk(SnmpVersion.Ver1, "1.3.6.1.2.1.1")
        If result IsNot Nothing Then
            Dim kvp As KeyValuePair(Of Oid, AsnType)
            For Each kvp In result
                Console.WriteLine("{0}: ({1}) {2}", kvp.Key.ToString(), _
                                  SnmpConstants.GetTypeName(kvp.Value.Type), _
                                  kvp.Value.ToString())
            Next
        Else
            Console.WriteLine("No results received.")
        End If
    End Sub
 
End Module

Imports System
Imports SnmpSharpNet
 
Module Module1
 
    Sub Main()
        ' SNMP Agent hostname or IP address
        Dim host As String = "localhost"
        ' SNMP community name - has to be read/write access for Set operation
        Dim community As String = "private"
        ' Dictionary to store values returned by GetBulk calls
        Dim result As Dictionary(Of Oid, AsnType)
        ' This is the Oid of the value we will change with this example
        Dim sysContactOid As Oid = New Oid("1.3.6.1.2.1.1.4.0")
        ' The new value for the above Oid
        Dim sysContactNewValue As OctetString = New OctetString("Support department - 555-333-4444")
        ' Initialize SimpleSnmp class
        Dim snmp As SimpleSnmp = New SimpleSnmp(host, community)
        If Not snmp.Valid Then
            Console.WriteLine("Invalid hostname/community.")
            Exit Sub
        End If
        ' Create an array of Variable Bindings (Vb class) of Oid/Values you with to set
        Dim vbCollection() As Vb
        ' Variable Binding contains an Oid and value associated with that Oid
        Dim vb As Vb = New Vb(sysContactOid, sysContactNewValue)
        ' Add one or more Vb classes to the collection
        vbCollection = New Vb() {vb}
 
        ' Make set request
        result = snmp.Set(SnmpVersion.Ver1, vbCollection)
 
        ' Check SNMP agent returned valid results
        If result IsNot Nothing Then
            Dim kvp As KeyValuePair(Of Oid, AsnType)
            ' Loop through returned values
            For Each kvp In result
                Console.WriteLine("{0}: ({1}) {2}", kvp.Key.ToString(), _
                                          SnmpConstants.GetTypeName(kvp.Value.Type), _
                                          kvp.Value.ToString())
            Next
        Else
            Console.WriteLine("Set operation failed.")
        End If
    End Sub
 
End Module

using System;
using System.Net;
using SnmpSharpNet;
 
namespace snmpget
{
    class Program
    {
        static void Main(string[] args)
        {
            // SNMP community name
            OctetString community = new OctetString("public");
 
            // Define agent parameters class
            AgentParameters param = new AgentParameters(community);
            // Set SNMP version to 1 (or 2)
            param.Version = SnmpVersion.Ver1;
            // Construct the agent address object
            // IpAddress class is easy to use here because
            //  it will try to resolve constructor parameter if it doesn't
            //  parse to an IP address
            IpAddress agent = new IpAddress("127.0.0.1");
 
            // Construct target
            UdpTarget target = new UdpTarget((IPAddress)agent, 161, 2000, 1);
 
            // Pdu class used for all requests
            Pdu pdu = new Pdu(PduType.Get);
            pdu.VbList.Add("1.3.6.1.2.1.1.1.0"); //sysDescr
            pdu.VbList.Add("1.3.6.1.2.1.1.2.0"); //sysObjectID
            pdu.VbList.Add("1.3.6.1.2.1.1.3.0"); //sysUpTime
            pdu.VbList.Add("1.3.6.1.2.1.1.4.0"); //sysContact
            pdu.VbList.Add("1.3.6.1.2.1.1.5.0"); //sysName
 
            // Make SNMP request
            SnmpV1Packet result = (SnmpV1Packet)target.Request(pdu, param);
 
            // If result is null then agent didn't reply or we couldn't parse the reply.
            if (result != null)
            {
                // ErrorStatus other then 0 is an error returned by 
                // the Agent - see SnmpConstants for error definitions
                if (result.Pdu.ErrorStatus != 0)
                {
                    // agent reported an error with the request
                    Console.WriteLine("Error in SNMP reply. Error {0} index {1}", 
                        result.Pdu.ErrorStatus,
                        result.Pdu.ErrorIndex);
                }
                else
                {
                    // Reply variables are returned in the same order as they were added
                    //  to the VbList
                    Console.WriteLine("sysDescr({0}) ({1}): {2}",
                        result.Pdu.VbList[0].Oid.ToString(), 
                        SnmpConstants.GetTypeName(result.Pdu.VbList[0].Value.Type),
                        result.Pdu.VbList[0].Value.ToString());
                    Console.WriteLine("sysObjectID({0}) ({1}): {2}",
                        result.Pdu.VbList[1].Oid.ToString(), 
                        SnmpConstants.GetTypeName(result.Pdu.VbList[1].Value.Type),
                        result.Pdu.VbList[1].Value.ToString());
                    Console.WriteLine("sysUpTime({0}) ({1}): {2}",
                        result.Pdu.VbList[2].Oid.ToString(), 
                        SnmpConstants.GetTypeName(result.Pdu.VbList[2].Value.Type),
                        result.Pdu.VbList[2].Value.ToString());
                    Console.WriteLine("sysContact({0}) ({1}): {2}",
                        result.Pdu.VbList[3].Oid.ToString(), 
                        SnmpConstants.GetTypeName(result.Pdu.VbList[3].Value.Type),
                        result.Pdu.VbList[3].Value.ToString());
                    Console.WriteLine("sysName({0}) ({1}): {2}",
                        result.Pdu.VbList[4].Oid.ToString(), 
                        SnmpConstants.GetTypeName(result.Pdu.VbList[4].Value.Type),
                        result.Pdu.VbList[4].Value.ToString());
                }
            }
            else
            {
                Console.WriteLine("No response received from SNMP agent.");
            }
            target.Close();
        }
    }
}

using System;
using SnmpSharpNet;
using System.Net;
 
namespace CSharpSet
{
  class Program
  {
    static void Main(string[] args)
    {
      // Prepare target
      UdpTarget target = new UdpTarget((IPAddress)new IpAddress("some-host-name"));
          // Create a SET PDU
      Pdu pdu = new Pdu(PduType.Set);
          // Set sysLocation.0 to a new string
      pdu.VbList.Add(new Oid("1.3.6.1.2.1.1.6.0"), new OctetString("Some other value"));
          // Set Agent security parameters
      AgentParameters aparam = new AgentParameters(SnmpVersion.Ver2, new OctetString("private"));
          // Response packet
      SnmpV2Packet response;
      try
      {
              // Send request and wait for response
        response = target.Request(pdu, aparam) as SnmpV2Packet;
      }
      catch (Exception ex)
      {
              // If exception happens, it will be returned here
        Console.WriteLine(String.Format("Request failed with exception: {0}", ex.Message));
        target.Close();
        return;
      }
          // Make sure we received a response
      if (response == null)
      {
        Console.WriteLine("Error in sending SNMP request.");
      }
      else
      {
              // Check if we received an SNMP error from the agent
        if (response.Pdu.ErrorStatus != 0)
        {
          Console.WriteLine(String.Format("SNMP agent returned ErrorStatus {0} on index {1}", 
          	response.Pdu.ErrorStatus, response.Pdu.ErrorIndex));
        }
        else
        {
          // Everything is ok. Agent will return the new value for the OID we changed
          Console.WriteLine(String.Format("Agent response {0}: {1}", 
          	response.Pdu[0].Oid.ToString(), response.Pdu[0].Value.ToString()));
        }
      }
    }
  }
}

Imports SnmpSharpNet
 
Module Module1
 
    Sub Main()
        ' Prepare target
        Dim target = New UdpTarget(New IpAddress("some-host"), 161, 1000, 0)
        ' Create a SET PDU
        Dim pdu = New Pdu(PduType.Set)
        ' Set sysLocation.0 to a new string
        pdu.VbList.Add(New Oid("1.3.6.1.2.1.1.6.0"), New OctetString("Test description"))
        ' Set Agent security parameters
        Dim aparam = New AgentParameters(SnmpVersion.Ver2, New OctetString("private"))
        ' Response packet
        Dim response As SnmpV2Packet
        Try
            ' Send request and wait for response
            response = target.Request(pdu, aparam)
        Catch ex As Exception
            ' If exception happens, it will be returned here
            Console.WriteLine(String.Format("Exception: {0}", ex.Message))
            target.Close()
            Return
        End Try
        ' Make sure we received a response
        If response Is Nothing Then
            Console.WriteLine("Error in sending SNMP request.")
        Else
            ' Check if we received an SNMP error from the agent
            If response.Pdu.ErrorStatus <> 0 Then
                Console.WriteLine(String.Format("SNMP agent returned ErrorStatus {0} on index {1}", response.Pdu.ErrorStatus, response.Pdu.ErrorIndex))
            Else
                ' Everything is ok. Agent will return the new value for the OID we changed
                Console.WriteLine(String.Format("Agent response {0}: {1}", response.Pdu(0).Oid.ToString(), response.Pdu(0).Value.ToString()))
            End If
        End If
        target.Close()
    End Sub
 
End Module

using System
using System.Net;
using System.Net.Sockets;
using SnmpSharpNet;
namespace traprecv {
	class Program {
		static void Main(string[] args) {
			// Construct a socket and bind it to the trap manager port 162 
			Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
			IPEndPoint ipep = new IPEndPoint(IPAddress.Any, 162);
			EndPoint ep = (EndPoint)ipep;
			socket.Bind(ep);
			// Disable timeout processing. Just block until packet is received 
			socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, 0);
			bool run = true;
			while (run) {
				byte[] indata = new byte[16 * 1024];
				// 16KB receive buffer int inlen = 0;
				IPEndPoint peer = new IPEndPoint(IPAddress.Any, 0);
				EndPoint inep = (EndPoint)peer;
				try {
					inlen = socket.ReceiveFrom(indata, ref inep);
				}
			 	catch( Exception ex ) {
					Console.WriteLine("Exception {0}", ex.Message);
					inlen = -1;
				}
			 	if (inlen > 0) {
					// Check protocol version int 
					ver = SnmpPacket.GetProtocolVersion(indata, inlen);
					if (ver == (int)SnmpVersion.Ver1) {
						// Parse SNMP Version 1 TRAP packet 
						SnmpV1TrapPacket pkt = new SnmpV1TrapPacket();
						pkt.decode(indata, inlen);
						Console.WriteLine("** SNMP Version 1 TRAP received from {0}:", inep.ToString());
						Console.WriteLine("*** Trap generic: {0}", pkt.Pdu.Generic);
						Console.WriteLine("*** Trap specific: {0}", pkt.Pdu.Specific);
						Console.WriteLine("*** Agent address: {0}", pkt.Pdu.AgentAddress.ToString());
						Console.WriteLine("*** Timestamp: {0}", pkt.Pdu.TimeStamp.ToString());
						Console.WriteLine("*** VarBind count: {0}", pkt.Pdu.VbList.Count);
						Console.WriteLine("*** VarBind content:");
						foreach (Vb v in pkt.Pdu.VbList) {
							Console.WriteLine("**** {0} {1}: {2}", v.Oid.ToString(), SnmpConstants.GetTypeName(v.Value.Type), v.Value.ToString());
						}
						Console.WriteLine("** End of SNMP Version 1 TRAP data.");
					} else {
						// Parse SNMP Version 2 TRAP packet 
						SnmpV2Packet pkt = new SnmpV2Packet();
						pkt.decode(indata, inlen);
						Console.WriteLine("** SNMP Version 2 TRAP received from {0}:", inep.ToString());
						if (pkt.Pdu.Type != (byte)PduType.V2Trap) {
							Console.WriteLine("*** NOT an SNMPv2 trap ****");
						} else {
							Console.WriteLine("*** Community: {0}", pkt.Community.ToString());
							Console.WriteLine("*** VarBind count: {0}", pkt.Pdu.VbList.Count);
							Console.WriteLine("*** VarBind content:");
							foreach (Vb v in pkt.Pdu.VbList) {
								Console.WriteLine("**** {0} {1}: {2}", 
								   v.Oid.ToString(), SnmpConstants.GetTypeName(v.Value.Type), v.Value.ToString());
							}
							Console.WriteLine("** End of SNMP Version 2 TRAP data.");
						}
					}
				} else {
					if (inlen == 0)
						Console.WriteLine("Zero length packet received.");
				}
			}
		}
	}
}