Hello everyone! I have a server/client application running in 4 internet cafes, and i have a packet duplication problem in one of them. I have thoroughly examined my code and tested it in my lab and cannot find any bugs whatsoever. So on rare conditions some of the clients seems to receive duplicate packets. (I installed wireshark to investigate the problem in the specific shop). I am not sure if this is causing my application to crash but i have nothing else to blame! :) So the question : **Is there any chance that faulty hardware (router, switches, NICs) or …

Member Avatar
Member Avatar
+0 forum 11

hi guys, i'm currently working on a project wherein i would enter a router's configuration using vb i've tried it on my netgear router by calling putty using vb and manually typing the commands on the console what i want to know is, if i'm using a software like packet tracer or gns3, can i connect this to vb and use it for my program, if possible how do i do it? thanks

Member Avatar
+0 forum 0

please any one can help me about send and recieve packets by serail port the pakeck that i need to send is in hex to controll some thing how can do this in vb.net how can do like this design in the picture below please help me

Member Avatar
Member Avatar
+0 forum 1

**edit** I just realized that Im on a single core machine atm (stupid work machine), so theortically the server isint actually executing on the CPU 50% of the time (while the client is running), so packets would be lost right? Or is there something else im missing alltogether? Ill post back once ive had a chance to run this code on my quad core at home. **/edit** Hello everybody. Im using Datagrams to create a UDP client / server relationship. This is my first real networking coding, with the exception of a little bit of TCP a while back. This …

Member Avatar
Member Avatar
+0 forum 3

how ca send the packet using button send to the serail port i recieved the packet but how send this packect through the serail port thanks for your reply the code is Imports System Imports System.ComponentModel Imports System.Threading Imports System.IO.Ports Public Class frmMain Dim myPort As Array 'COM Ports detected on the system will be stored here Delegate Sub SetTextCallback(ByVal [text] As String) 'Added to prevent threading errors during receiveing of data Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load ' When our form loads, auto detect all serial ports in the system and populate the …

Member Avatar
Member Avatar
+0 forum 1

I posted this somewhere else but I think it was deleted so I'll post it as a new question... Here's my problem; I've been developing a packet sniffer using the Jpcap library from http://netresearch.ics.uci.edu/ . I was developing using the windows version of the java library, but now I realize that it's the linux version I will need, but as the website's not working, (check the link, I think the servers down) I can't download this version. Does anyone have this saved to there computer? I know the website may be fixed in the future but I don't really want …

Member Avatar
Member Avatar
+0 forum 1

I'm trying to develop a packet sniffer using java and I've been using the JpCap library to capture the packets. I've run into a problem where Jpcap is capturing the packets from the NIC on my desktop, but I need to capture the packets from the gateway (MikroTik RouterBOARD) and not just the packets coming into my system. I've been reading into 'promiscuous mode', a parameter passed into the JpcapCaptor.OpenDevice() method. I'm a bit confused about it, will promiscuous mode capture the packets from my router or does it do something else? Sorry if I haven't explained it properly. here's …

Member Avatar
+0 forum 0

I'm required to write a packet sniffer in the C programming language and Identify the Packet as IP, ARP, or Broadcast and count how many packets of each. I'm able to get IP packets identified and counted, but don't seem to be seeing any ARP or Broadcasts correctly or count them. I also get this warning when I compile my code: /netdump.c: In function 'raw_print': ./netdump.c:284: warning: cast to pointer from integer of different size ./netdump.c:285: warning: comparison between pointer and integer Any help is appreciated!!! I'm more concerned with why I'm not getting any ARP or Broadcast packets being …

Member Avatar
Member Avatar
+0 forum 1

Hello guys i'm currently having difficulties with pinging different vlans whether they are on the same switch or not. I have 3 vlans: vlan 30, vlan 40, vlan 50. I have 1 switch which I use as the VTP server and 7 switches connected to it which I use as the VTP clients I can ping all PCs on vlan 30 no matter what switch they are connected to, same for vlan 40 and 50. The problem is that I can't ping different vlans i.e can't ping PC on vlan 30 to PC on vlan 50. I have tried to …

Member Avatar
Member Avatar
+0 forum 3

Hello , i built a network topology on packet tracer a while ago using a computer that is not mine. i saved the file and now when i open it on my computer i can't see the commands that i have entered before. is there a way to show these commands? to be honest , i don't recall exporting anything.

Member Avatar
Member Avatar
+0 forum 1

**Before you start complaining that this has been asked before, please hear me out** Hello, I've been trying to write an simple application for windows that can send and recieve packetts over a network. I'm hoping to find some simple library that can simply open the port, and send a packett of data through. This doesn't need to connect to an external network, although instructions on how to do that would be greatly appreciated. One last thing, if you could explain how to impliment these pieces of code, that would be great. I'm not very good at taking snippets of …

Member Avatar
Member Avatar
+0 forum 2

I want to create a message table, where every incoming message is saved as a row in a message. According to the picture below. Any introductory help will be very helpful. I already have á application where the messages are printed on a textarea, but for further inhancment I want each message as a packet showing like below. when I click on each message it will open a frame where the message will be shown. ![](/attachments/large/2/Mockup_Status_Tab1.png "Mockup_Status_Tab1")

Member Avatar
Member Avatar
+0 forum 1

How would I be able to get all incoming packets, in C#? I have absolutely no idea on how to get started, so could you guys help me out? Thanks.

Member Avatar
Member Avatar
+0 forum 3

Question is: [B]How can I send two strings using SendData in different packets?[/B] Because when I try to send two strings one after another, winsock joins them in a single packet thus making one string received from client/server. For example: [CODE]Winsock1.SendData "String1" Winsock1.SendData "String2"[/CODE] The final received data will be: "String1String2" I guess winsock joins data that are sent in short period of time, is there any way to avoid this? If the packets are analyzed by any sniffer software, there will be one packet containing both strings. Is there any way I can send these two strings separately, in …

Member Avatar
Member Avatar
+0 forum 2

Hi All, I have a problem on one of my site where I have Quintum VOIP gateways in 2 separate buildings that are connected with a Fiber link. When running the ping command I loose packets to the Quintums but not to PC's. Today their Exchange server went down and for a while I had no packet loss. When removing the Quintums from their network and putting them on a separate switch, I get no packet loss.We have moved the Quintums to different switches, replaced the patch leads. Any help will be greatly appreciated. Thank you Max

Member Avatar
Member Avatar
+0 forum 2

Hey guys I am a noob when it comes to this stuff. I go to college for electrical engineering and me and my professor were discussing a cool senior project. There are regular vending machines in most buildings of the school that are connected to the schools network. The ethernet cords are out in the open. This way kids can swipe their school ID's for a soda and get charged through their dining dollars. Their ID #'s are sent to the schools computer which deducts from their account. Is there a way to build a packet sniffer and connect it …

Member Avatar
Member Avatar
+0 forum 1

I am a beginner in Jpcap. My problem is as follows:- i am trying to send a TCP packet but unable to receive it. The code for sending Tcp packet is as follows. I am working on Windows XP. hoping for reply. [CODE]//code for sending import jpcap.*; import jpcap.packet.*; import java.net.InetAddress; import java.lang.Object; class SendPacket { public static void main(String args[]) throws Exception { int index=0; //Obtain the list of network interfaces NetworkInterface[] devices = JpcapCaptor.getDeviceList(); //open a network interface to send a packet to JpcapSender sender=JpcapSender.openDevice(devices[index]); //create a TCP packet with specified port numbers, flags, and other parameters TCPPacket …

Member Avatar
+0 forum 0

[B]I am doing a mini project on traffic redundancy elimination methods as my mini project...i want to know how to monitor and find repetitive http requests traverse through a pc acting as aproxy server (eg: like a no: of laptops connected to a single lap acting as a proxy server) .any help would be appreciated...[/B]...

Member Avatar
+0 forum 0

Ok this is so new to me but does anyone have example code that decodes header fields in an IP datagram? or a link to something like the beej's guide....So i need to decode the header from the following example. 0000000 141724 120662 000002 000004 000000 000000 000000 000000 0000020 177777 000000 000001 000000 142167 045720 175323 000001 0000040 000146 000000 000146 000000 010000 177733 120040 006000 0000060 134051 122150 000010 010105 054000 153336 000100 003100 0000100 111425 022620 046250 125514 004701 013000 042602 044146 0000120 164312 036636 030340 014120 010070 161701 000000 025433 0000140 050532 067325 046066 000014 121441 …

Member Avatar
Member Avatar
+0 forum 14

Hello everyone, I'm having trouble with a code I need to write, I have never coded in C and I need to do this program in C. I have created my checksum code already and need to implement this: I need to send a complete ASCII file in 128 byte packets including the checksum. The sender takes the ASCII file as input sends a 128 byte packet on the data queue then waits specified timeout on the control queue for an acknowledgement. If a timeout is incurred the sender sends the packet again - up to three times before giving …

Member Avatar
Member Avatar
+0 forum 10

There is a good tool for pcap base protocol testing. You can modify the pcap by using this tool. [URL="http://www.packetsquare.com"]http://www.packetsquare.com[/URL] packetsquare is a open-source packet modification tool. It is used for protocol testing and hacking. This tool is capable to parse and modify Ethernet II, VLAN(802.1Q), MPLS, ARP, IPv4, ICMP, TCP, UDP, IGMPv3 protocols & this tool is having some unique features like Stream Based Packet field modification, Packet Deletion/Duplication/Reordering, IP and MAC Address Find And Replace, Auto CheckSum for IP/ICMP/IGMP/TCP/UDP, Pcap Replay (Selected Single packet/Multiple packets).

Member Avatar
Member Avatar
+0 forum 2

Hello everybody! I have a game server (WoW). I want my players to download my custom patches to the game. I've done a program that checks for update/downloading things. I want my program to send a packet to my game server if player have all my patches. I dont need any response from the server, it will handle it, but its another story. So I want to know, how to send a packet to a server. Thank you!

Member Avatar
Member Avatar
+0 forum 1

Call it a kind of bigotry for the new millennium. The packets of peer-to-peer applications such as BitTorrent have become the target of throttling—even complete blockage—by Internet service providers on their networks. Do they have the right? The revelation comes from [URL=http://broadband.mpi-sws.mpg.de/transparency/results/]study results [/URL] published yesterday by Germany’s [URL=http://www.mpi-sws.org/]Max Plunk Institute of Software Systems[/URL] computer research group, which identified 13 ISPs engaged in the practices, including Comcast, Cox and seven others in the U.S. In response, Comcast said it monitors peek traffic times and slows peer-to-peer packets to give other services access. Data in the study contradicts that claim, showing …

Member Avatar
Member Avatar
+0 forum 4

Bram Cohen, the creator of bittorrent.com has signed a deal with the Movie Industry, that is hoped will reduce the number of pirated films, shared on the Internet, via the website. The deal means that BitTorrent must remove any links to pirated films. The deal between the Motion Picture Association of America (MPAA) and BitTorrent is the latest in a line of moves to limit the illegal sharing of films via the Internet. Mr Cohen has raised $8.75m to turn the BitTorrent Inc into a commercial download service, similar to Napster, who made a likewise transition. "We are glad that …

Member Avatar
Member Avatar
+0 forum 2

The End.