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AnswerRe: Adding images from database to word document Pin
Dave Kreskowiak30-Sep-09 1:57
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Questionread excel cell Pin
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freakyit29-Sep-09 21:26
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QuestionCrystal Report Loading Failed. Pin
waner michaud29-Sep-09 8:58
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AnswerRe: Crystal Report Loading Failed. Pin
Paramhans Dubey29-Sep-09 22:27
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QuestionSend Hex code by UDP Pin
phil241529-Sep-09 6:02
phil241529-Sep-09 6:02 
Hello,

I'm pretty au fait with VB.NET but a complete novice to programming anything to do with networking. I'm trying to replicate the behaviour of one small part of an application we have so that I can build my own application which will be much simpler for our staff to use to perform that one function. The application is a server program.

Anyway, using various network sniffers I've identified the packets that the application sends. It seems that when it starts up it broadcasts a UDP packet over the network, and then the clients respond with ICMP echos, after which further TCP packets are sent to the clients. Well, I'm stuck at the first hurdle!

I need, to begin with, to replicate that initial UDP broadcast. Using .NET and lots of Googling I've been able to produce code which will send a UDP packet to the right IP and port. What I'm struggling with is the data of the packet. Because I have the packet as captured in SoftPerfect Network Protocol Analyser (much more user-friendly than Wireshark for my money) I know exactly what the packet should look like and I can even copy the hex of the original packet.

I can't then simply stick this hex code into a string and send it over UDP, it doesn't work. Presumably it needs to be in some kind of array, but all the references I can find to this online seem to involve CONVERTING a string to hex or hex to bytes. Surely since I already have the hex no conversion should be necessary? I just want to send it exactly as it is! When I did convert it to a byte array (if that's the right term, this is very new to me) and then sent it the network sniffer picked it up and the data in the packet was very different and much longer than the original one I'm trying to replicate.

Any help or advice would be greatly appreciated, from general tips about replicating network packets to actual code I can copy!

Thanks in advance.
AnswerRe: Send Hex code by UDP Pin
Dave Kreskowiak29-Sep-09 6:23
mveDave Kreskowiak29-Sep-09 6:23 
AnswerRe: Send Hex code by UDP Pin
Luc Pattyn29-Sep-09 6:26
sitebuilderLuc Pattyn29-Sep-09 6:26 
GeneralRe: Send Hex code by UDP Pin
phil241530-Sep-09 0:42
phil241530-Sep-09 0:42 
AnswerRe: Send Hex code by UDP Pin
phil241530-Sep-09 23:41
phil241530-Sep-09 23:41 
QuestionVS 2008 Setup Pin
εїзεїзεїз29-Sep-09 4:40
εїзεїзεїз29-Sep-09 4:40 
AnswerRe: VS 2008 Setup Pin
Dave Kreskowiak29-Sep-09 5:40
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GeneralRe: VS 2008 Setup Pin
εїзεїзεїз29-Sep-09 6:24
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GeneralRe: VS 2008 Setup Pin
Dave Kreskowiak29-Sep-09 7:34
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GeneralRe: VS 2008 Setup Pin
εїзεїзεїз29-Sep-09 8:38
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GeneralRe: VS 2008 Setup Pin
Dave Kreskowiak29-Sep-09 8:43
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GeneralRe: VS 2008 Setup Pin
εїзεїзεїз29-Sep-09 9:14
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GeneralRe: VS 2008 Setup Pin
Dave Kreskowiak29-Sep-09 10:41
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GeneralRe: VS 2008 Setup Pin
εїзεїзεїз29-Sep-09 11:44
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GeneralRe: VS 2008 Setup Pin
Dave Kreskowiak30-Sep-09 1:54
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GeneralRe: VS 2008 Setup Pin
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QuestionGetting data into an array. Pin
vurdmal29-Sep-09 2:58
vurdmal29-Sep-09 2:58 
AnswerRe: Getting data into an array. Pin
Paramhans Dubey29-Sep-09 3:07
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