I realize this is a broad question, but how do I recieve / send packets. I know what packets I need to send and what Im going to recieve, but I dont know how to send / recieve them.
View 8 RepliesI need to include in my application that can receive connections from a client( or two).I am thinking, that I would like to have the clients send a "TelegramID" so that I may now how to process the code.Following the "TelegramID" would be a structure that would need to be processed.So far, I can use a single client and send just plain text but need some direction for my end goals.
View 2 RepliesI have created a Client that can send and receive data via TCP sockets. The objects stored on the serverside are the *exact* same object used for the client. They use the same send and receive protocols.
Now, when i send a string from the server to the client , it does precisely what it should do. However when I send a string to the server.... I do receive the string as an equal length of NULL characters. I run the server and client locally.
Basicly what can influence the behaviour between two completely identical objects performing the exact same task? I wonder if there is some socketflag issue if the TCPlistener.accept function returns a completely different setup then the one I R used to.
(if it is of any interest, the send protocol is asynchronious)
I am facing problem in asynchronous socket communication.
1)I wanted to perform connect(from client to server) operation on enter button and send the data whatever client want to send and disconnect from server. And again client should get connect to server whenever client wanted to send data. this is the mechanism.
i.e how to reuse the socket.
2)Again Server should able to send the data to client.
Below is my code, but when i send the message thru client socket i receive Specified argument was out of the range of valid values. Parameter name: size
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim serverStream As NetworkStream = clientSocket.GetStream()
Dim outStream As Byte() = _
System.Text.Encoding.ASCII.GetBytes("0800822000000000000004000000000000000920092126012345001")
[CODE]...
I have these following lines to send bytes using socket
Dim server As New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
Dim myIp As IPAddress = IPAddress.Parse("myIP")
Dim ip As New IPEndPoint(myIp, Int32.Parse("myPort"))
[Code]....
As in the code, I am supposed to retrieved "Halo". Instead I keep receiving sth like "[]".
I coded a small tcp server/client software implementing the async methods of the socket object. In order to keep track and control of the transfered data on both sides, I decided to wrap the bytes to be transfered into small 65 000 bytes packets, sent one after each other, in varying order.In most cases, it works perfectly, and it is impressively fast. However, when I want to transfer larger data than my usual requests, say like a dozen megabytes, crippling problems start to appear, out of shit.Effectively, it seems that somehow when executed without pauses, the server sends the packets too fast, or that the client receives it too slowly. However, if I put the SendAsync method's thread to sleep for like 100ms before sendingthe next packet, everything arrives without problem on the client.[code]
View 1 RepliesI have to create an application that can receive/send SMS using GSM Modem.
View 4 RepliesI need to send data via serial and wait for and answer (VB.NET).Right now i'm doing it this way:SerialPort1.Write(sel & Chr(13))Thread.Sleep(50)aaa = SerialPort1.ReadExisting()If i do not thread.sleep, i get nothing, i supose it's because the machine is too fast.
View 1 RepliesWhat Visual Basic code can be used to assemble and send a raw packet, and receive response packets? I looked on MSDN and I couldn't find any documentation for anything used to send a packet.
View 2 RepliesI have a USB modem that can detect caller ID and can detect dialled digits when special AT commands activated, How to send and receive data. The sent data will be the AT command such as AT+VCID-1 to activate the caller ID, the received data will be caller ID information and the digits dialed. I'm new to prgramming and using Visual Basic 2008 Express.
View 8 Replieshow to do socket programming in VB. I'm using VB.NET 2008 and i'm a novice but with a reasonable understanding of programming so I want to learn by examples and understanding it in a novice/intermediate point of view. Essentially, I want to create a simple TCP or UDP client that can connect to an IP and port and retrieve the stream for parsing of content.
View 5 Repliesi'm currently using my computer as host and client.. i ran the program and the console application for the server started.. but how will i be able to run the form application for the client? can VS run 2 programs at the same time?
View 6 RepliesI am using VB2008 Express and am curious how to send a command via RS232 communications. The string that I need to send is 02h PON 03h. The start and end bits are 02h and 03h.
How can I convert 02h and 03h to its ascii form. In hyperterminal, I use the sequence {(hold)ALT 0 0 2} on the number pad to send the start bit.
I am using this code currently without the start and end bits
Code:
I have found a simple UDP project at [URL] which is a project written in VB2003. I have imported it into VB2008 Express edition. I have no problems with the send part of the project. I'm able to send messages to internal (eg. 127.000.000.001) and external (in my case the other device has 192.168.0.100) addresses. Now for the receive part... I'm able to receive messagess sent form the same computer (127.000.000.001) but none of the packets are being received by the aplication if sent from an external source.
[Code]...
Using the Socket raw, with XP I can read without problems both the incoming packets and the outgoing packets. With Vista (I have tried also others Sniffers) is impossible to see the outgoing packets...WHY? what I have to do to see alse the outgoing packets? In reality I have not to read packet data or packet lenght... I need only to count the number of incoming packets and outgoing packets... but with Vista this job seems impossible... or not?
View 1 RepliesMy client program gets stuck on NetworkStream.Read even though the server is reporting it's sending the message. The client and server are running on the same computer.Full server code (console application)
Imports System.Net.Sockets
Imports System.Text
Module Module1
Sub Main()
[Code]...
I'm working on an application that communicates to torque controllers on the factor floor. The user inputs an IP address and a port and clicks the btnConnect button to make the initial connection. Once that completes a KeepAlive message must be sent periodically to maintain communication with the torque controller. The initial connection works very well but a socket error (see below) grinds everything to a halt when the KeepAlive message is sent. I would appreiciate any ideas the readers may have on the root cause. I'm quite confused because basically the same code is use for both the initial connection and then the KeepAlive messages. I have pasted some of the code as well below.
[code]...
I converted some codes from python to VB 2010. My aim is sending query data to multicast IP and get the response. My query data receiving from device which is connected to my LAN. Also the device responding my query and my PC receiving the responce but at this point the VB program freezing.getting response data and printing to console without freezing.
This is the code list;
Imports System.Net
Imports System.Net.Sockets
Imports System.Text
[code]....
Here is the Wire Shark (Network Protocol Anlyzer) screen shots; My computer IP is : 192.168.0.11 and device's IP is : 192.168.0.10.
I am trying to implement SMPP protocol in vb. I am sucessfull in send and receiving packets using sockets. Now I would like to decentralize the functions of my program. I want to implement two programs one for sending and another for receiving using a single socket. I want to receive data through the same socket that was created in another process(i.e., the first program).
View 1 RepliesI am having trouble with a socket client application written in vb.net using Visual Studio 2005. The client connects to a C language socket server that is running on OpenVMS. The problem that I have is that when the server sends a packet, the client does not receive the last byte (of every packet!). I can dump the packets on the network and the data is all there. My current solution is to keep my socket messages short (247 bytes) and send one extra byte past the end of my data.
I would like to include more information in my messages and I cannot find a way to make this work. If I knew 100% how long the packets will be on the network, I could work around this by including an extra byte in just the right places. However, I don't want to make any assumptions about the length of the packets.
Here is a sample of my client receive code:
Private Sub ReceiveMsg()
Dim nTotalBytes As Integer
Dim nNumBytes As Integer
[Code]....
I've looked through a lot of snippets online and I see a lot of things similar to
Dim bytes(tcpClient.ReceiveBufferSize) As Byte
networkStream.Read(bytes, 0, CInt(tcpClient.ReceiveBufferSize))
but what I am unsure of when to call such a thing? How do I know when there is data to receive...in visual basic 6 with winsock, there was a specific routine which was called upon data arrival, but I see nothing of the sort for vbNet.
I am using VB.NET and I am designing a generic network architecture in which data can be transmitted in various ways. I am wanting to strip down things as much as possible, and I do not want to transmit in plain text. My question today is regarding ideas and example code (if applicable) as far as parsing binary data that is sent over the wire in VB.NET.I want each packet to have a very generic architecture such as <packet type> <address> <payload> or whatnot. I understand that I can use certain bytes as delimiters for these packet fields. I don't necessarily want to serialize everything being that for security reasons, the same library has to be used to deserialize the data.
a) Put my protocol into binary data where each field is delimited using a certain byte
b) Parse that data from binary at the other end.
Once again, I don't want to use plaintext since this can cause a bunch of overhead in comparison.
I am new to socket communication. I found a few samples on the web and I managed to make my own host-client communication but i wanted to go a bit further and connect to port 80 of a server and it was just a disaster! First of all I know I can just use the functions that vb has itself but I want to make my own connections ... I have got some reasons I need this one! Do I really have to make them "connect" or just somehow without connecting I get the data? So I'm stack at the point that the connection is made ... it refuses to connect.
View 7 RepliesWhile using the Socket.Receive method to receive messages through network, you should define a variable as the buffer and you have to specify the length like this: Code: Dim _ReadBuffer As Byte() = New Byte(LENGTH) {} My question is: What is the bad thing about increasing the length of this variable even if the received messages are sometimes shorter? (i.e. if some body let it 10000).
View 1 RepliesI am trying to recieve HEX data from a seriall device. Code is as below . but the required output is not correct. Some chracter code are not correct even in decimal. like for 80 i recieved 3F and for c0 also. for example i recived a string .
10 02 3F 00 10 03 3F 61
but in actual data should be
10 02 80 00 10 03 c0 61
Public Sub DataSeriallReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort.DataReceived
Dim buff As String
[Code].....
I'm trying to receive data from the serial port and display onto a text box in my gui in vb. I'm using xp pro sp2 and vb 2008 exp.What i've done so far:
- I'm able to send data successfully (tested) to the serial port
- I can dispaly what data is being sent (tested)
Steps taken:
- I have looked around on this forum for something similar to what I have but no similar posts are here
- Will look into MSDN help shortly
- Will also try some vb books I have lying around. But the problem is most of the vb books deal with sql server and database stuff and not really interfacing to hardware.
I would like to know can we use a socket connection on vb to communicate with PC without using GSM modem and SIM card.for example, like sendin a simple text msg to the PC and it will reply back the result back to me the result.
View 1 Repliesi'm creating an Asynchronous socket programming in vb.net. i've utilised the code from Asynchronous client and server code frtom the following links:m a new user so could post only one link fully)When I try to connect the for more than one client the second client always waits until the first clientcompletes the call. i want the clients to accept calls at the same time
View 1 RepliesI've been making this project for our Major course in Networking Principles and Programming. Our project is an ATM System but with the use of Socket API. My partner and I chose VB.NET even if we're completely beginners.
We've researched about Socket programming in VB.NET, and we're glad that our Client-Server connection worked out. The problem is, our system contains many forms (Withdraw, Deposit, etc). We've researched the Google about Socket Programming in many Window Forms and unfortunately, we can't find any.
How can we be able to maintain the connection with many forms? Or do we have to create a new connection on every form? Is it better to create only ONE form for the client application perhaps?