public void connect(int connectTimeout) 
		{
			if(_isConnected)
			{
				throw new JSchException("session is already connected");
			}
			io=new IO();
			if(random==null)
			{
				try
				{
					Class c=Class.forName(getConfig("random"));
					random=(Random)(c.newInstance());
				}
				catch(Exception e)
				{
					System.Console.Error.WriteLine("connect: random "+e);
				}
			}
			Packet.setRandom(random);

			try	
			{
				int i, j;
				int pad=0;

				if(proxy==null)
				{
					proxy=jsch.getProxy(host);
					if(proxy!=null)
					{
						lock(proxy)
						{
							proxy.close();
						}
					}
				}

				if(proxy==null)
				{
					Stream In;
					Stream Out;
					if(socket_factory==null)
					{
						socket=Util.createSocket(host, port, connectTimeout);
						In=socket.getInputStream();
						Out=socket.getOutputStream();
					}
					else
					{
						socket=socket_factory.createSocket(host, port);
						In=socket_factory.getInputStream(socket);
						Out=socket_factory.getOutputStream(socket);
					}
					//if(timeout>0){ socket.setSoTimeout(timeout); }
					socket.setTcpNoDelay(true);
					io.setInputStream(In);
					io.setOutputStream(Out);
				}
				else
				{
					lock(proxy)
					{
						proxy.connect(socket_factory, host, port, connectTimeout);
						io.setInputStream(proxy.getInputStream());
						io.setOutputStream(proxy.getOutputStream());
						socket=proxy.getSocket();
					}
				}

				if(connectTimeout>0 && socket!=null)
				{
					socket.setSoTimeout(connectTimeout);
				}

				_isConnected=true;

				while(true)
				{

					i=0;
					j=0;
					while(i<buf.buffer.Length)
					{
						j=io.getByte();
						if(j<0)break;
						buf.buffer[i]=(byte)j; i++;
						if(j==10)break;
					}
					if(j<0)
					{
						throw new JSchException("connection is closed by foreign host");
					}

					if(buf.buffer[i-1]==10)
					{    // 0x0a
						i--;
						if(buf.buffer[i-1]==13)
						{  // 0x0d
							i--;
						}
					}

					if(i>4 && (i!=buf.buffer.Length) &&
						(buf.buffer[0]!='S'||buf.buffer[1]!='S'||
						buf.buffer[2]!='H'||buf.buffer[3]!='-'))
					{
						//System.err.println(new String(buf.buffer, 0, i);
						continue;
					}

					if(i==buf.buffer.Length ||
						i<7 ||                                      // SSH-1.99 or SSH-2.0
						(buf.buffer[4]=='1' && buf.buffer[6]!='9')  // SSH-1.5
						)
					{
						throw new JSchException("invalid server's version String");
					}
					break;
				}				

				V_S=new byte[i]; Tamir.SharpSsh.java.System.arraycopy(buf.buffer, 0, V_S, 0, i);
				//System.Console.WriteLine("V_S: ("+i+") ["+new String(V_S)+"]");

				//io.put(V_C, 0, V_C.Length); io.put("\n".getBytes(), 0, 1);
			{
				// Some Cisco devices will miss to read '\n' if it is sent separately.
				byte[] foo=new byte[V_C.Length+1];
				Tamir.SharpSsh.java.System.arraycopy(V_C, 0, foo, 0, V_C.Length);
				foo[foo.Length-1]=(byte)'\n';
				io.put(foo, 0, foo.Length);
			}

				buf=read(buf);
				//System.Console.WriteLine("read: 20 ? "+buf.buffer[5]);
				if(buf.buffer[5]!=SSH_MSG_KEXINIT)
				{
					throw new JSchException("invalid protocol: "+buf.buffer[5]);
				}
				KeyExchange kex=receive_kexinit(buf);

				while(true)
				{
					buf=read(buf);
					if(kex.getState()==buf.buffer[5])
					{
						bool result=kex.next(buf);
						if(!result)
						{
							//System.Console.WriteLine("verify: "+result);
							in_kex=false;
							throw new JSchException("verify: "+result);
						}
					}
					else
					{
						in_kex=false;
						throw new JSchException("invalid protocol(kex): "+buf.buffer[5]);
					}
					if(kex.getState()==KeyExchange.STATE_END)
					{
						break;
					}
				}

				try{ checkHost(host, kex); }
				catch(JSchException ee)
				{
					in_kex=false;
					throw ee;
				}

				send_newkeys();

				// receive SSH_MSG_NEWKEYS(21)
				buf=read(buf);
				//System.Console.WriteLine("read: 21 ? "+buf.buffer[5]);
				if(buf.buffer[5]==SSH_MSG_NEWKEYS)
				{
					receive_newkeys(buf, kex);
				}
				else
				{
					in_kex=false;
					throw new JSchException("invalid protocol(newkyes): "+buf.buffer[5]);
				}

				bool auth=false;
				bool auth_cancel=false;

				UserAuthNone usn=new UserAuthNone(userinfo);
				auth=usn.start(this);

				String methods=null;
				if(!auth)
				{
					methods=usn.getMethods();
					if(methods!=null)
					{
						methods=methods.toLowerCase();
					}
					else
					{
						// methods: publickey,password,keyboard-interactive
						methods="publickey,password,keyboard-interactive";
					}
				}

			loop:
				while(true)
				{

					//System.Console.WriteLine("methods: "+methods);

					while(!auth &&
						methods!=null && methods.Length()>0)
					{

						//System.Console.WriteLine("  methods: "+methods);

						UserAuth us=null;
						if(methods.startsWith("publickey"))
						{
							//System.Console.WriteLine("   jsch.identities.size()="+jsch.identities.size());
							lock(jsch.identities)
							{
								if(jsch.identities.size()>0)
								{
									us=new UserAuthPublicKey(userinfo);
								}
							}
						}
						else if(methods.startsWith("keyboard-interactive"))
						{
							if(userinfo is UIKeyboardInteractive)
							{
								us=new UserAuthKeyboardInteractive(userinfo);
							}
						}
						else if(methods.startsWith("password"))
						{
							us=new UserAuthPassword(userinfo);
						}
						if(us!=null)
						{
							try
							{
								auth=us.start(this);
								auth_cancel=false;
							}
							catch(JSchAuthCancelException ee)
							{
								//System.Console.WriteLine(ee);
								auth_cancel=true;
							}
							catch(JSchPartialAuthException ee)
							{
								methods=ee.getMethods();
								//System.Console.WriteLine("PartialAuth: "+methods);
								auth_cancel=false;
								continue;//loop;
							}
							catch(RuntimeException ee)
							{
								throw ee;
							}
							catch(Exception ee)
							{
								System.Console.WriteLine("ee: "+ee); // SSH_MSG_DISCONNECT: 2 Too many authentication failures
							}
						}
						if(!auth)
						{
							int comma=methods.indexOf(",");
							if(comma==-1) break;
							methods=methods.subString(comma+1);
						}
					}
					break;
				}

				if(connectTimeout>0 || timeout>0)
				{
					socket.setSoTimeout(timeout);
				}

				if(auth)
				{
					isAuthed=true;
					connectThread=new Thread(this);
					connectThread.setName("Connect thread "+host+" session");
					connectThread.start();
					return;
				}
				if(auth_cancel)
					throw new JSchException("Auth cancel");
				throw new JSchException("Auth fail");
			}
			catch(Exception e) 
			{
				in_kex=false;
				if(_isConnected)
				{
					try
					{
						packet.reset();
						buf.putByte((byte)SSH_MSG_DISCONNECT);
						buf.putInt(3);
						buf.putString(new String(e.ToString()).getBytes());
						buf.putString(new String("en").getBytes());
						write(packet);
						disconnect();
					}
					catch(Exception ee)
					{
					}
				}
				_isConnected=false;
				//e.printStackTrace();
				if(e is RuntimeException) throw (RuntimeException)e;
				if(e is JSchException) throw (JSchException)e;
				throw new JSchException("Session.connect: "+e);
			}
		}