1. How much load or data size our custom encryption/decryption algorithm can handle? E.g. what's the limit of file size that normal encryption/decryption algorithm supports.
2. What's the best way to use encryption while file transfer via internet?
3. Where and when encryption and decryption has to apply while uploading and downloading content from internet(Hosting on client or server machines)?
4. What type of algorithms suites for above approaches?
5. How much time it takes to encrypt / decrypt data for 10 MB, 100 MB, 1 GB etc
I am trying to make file transfer program in vb.net 2008 for big files eg. 10 GB.i was able to code simple socket program to transfer files with small size by using Sockets but if the file is large then "File.ReadAllBytes(ComboBox1.Text)" command will not work cause it use lot of memory & if the file is really big i.e. 10 GB it give not enough memory error, so i made a loop that sends data in small amounts, but this give me a larger file size with repeated data at end of the file.
I have used the following code to get bandwidthIt works but i have following doubts1.I need Total Internet Data transferred in MB, how do i convert?, total data transferred (download+upload) varies with other bandwidth monitoring applications. how do i get exact data transferred?2.I need to exclude file transfer in local LAN in Data Transfer, The follwoing method includes internet data transfer + Local file transfer
Option Explicit Public Enum OperationalStates MIB_IF_OPER_STATUS_NON_OPERATIONAL = 0
ive been trying to use System.Security.Cryptography to encrypt and decrypt a file but its not working for me
this code
Private Sub EncryptFile(ByVal sInputFilename As String, ByVal sOutputFilename As String, ByVal sKey As String) Dim fsInput As New FileStream(sInputFilename, FileMode.Open, FileAccess.Read) Dim fsEncrypted As New FileStream(sOutputFilename, FileMode.Create, FileAccess.Write) Dim DES As New DESCryptoServiceProvider()
I would like to read the contents of an existing Outlook 2007 PST file by VB.Net. I find already the file and record structure, this is not a problem. But I have a problem with the compressible encryption how is used. Now I have read that this encryption is based on a simple byte-substitution cipher with a fixed substitution table. But unfortunately I can't find this table. Maybe someone can help me where to find this table or where I to find all the necessary information about compressible encryption.
Imports System Imports System.IO Imports System.Security Imports System.Security.Cryptography
[code]....
The above code is used by me to encrypt .avi files and it worked very well but the problem is that if the size of my video file is greater than 200 mb memory overflows probably as the code copy the whole input file into ram and then process it hence it put limitation of hardware,is there any better way to do it so that files > 200 mb could me encrypted in PCs with 1gb ram?
I'm looking for advice/ideas in regards to ongoing file encryption.I have an event that fires frequently that contains small amounts of data passed through the eventargs.This data is then written out to disk (currently unencrypted).I need to encrypt this data (which, I can do).My attempt in the first five minutes was unencrypting the file, appending the data and reencrypting the file.This obviously works, but is pretty inefficient and not going to be my solution since the file could grow rather large and the resources to unecrypt/ encrypt grow larger as the file grows larger.My next thought was to encrypt each set of data as it's written out and have some kind of marker in the file to denote where to split so I could unencrypt each chunk to reproduce the original file.I'm leaning towards this approach now (though by encrypting small chunks of data multiple times, the file size will be considerably larger.As an example, if I encrypt each letter of the alphabet the file is approx 8 times larger than if I encrypted a string with all of the letters of the alphabet in this case each files decrypted content would be identitcal).
I am trying to make a key that will be used in file encryption/decryption for my application. However, there is no user data involved with this application (As i would usually use the user's password to generate the encryption key), so i have to turn to another method.
I am thinking that maybe it is possible to generate a completely random key the first time the program runs, then save this key inside the program so that it is inaccessible by the user. The user will not be shown this key, but the key MUST be randomly generated for each application, and it also must stay constant once it is created.
I have set up a method in vb.net and in xcode for encrypting a string using as far as i can tell the same parameters for an AES encryption.I've looked all over the place but cannot find information on whether they use the same encryption algorithm and settings.
this is the vb.net code:
Dim encryptAES As New AesCryptoServiceProvider() Dim encoding As New UTF8Encoding() Dim encryptor As ICryptoTransform encryptAES.Key = encoding.GetBytes("12345678901234567890123456789032") encryptAES.IV = encoding.GetBytes("1234567890123416") encryptAES.Mode = CipherMode.CBC
I will use the Background Intelligent Transfer Service (BITS) to transfer files from a client (laptop) to a shared folder on a server within our local network.The problem is a very slow network bandwith, if we transfer a file, the other clients canīt work, all requests to other clients (application) or viewing internet pages needs a long time.My idea is to use BITS in my tool to copy/transfer a file from client to server, also I hope to get more performance for the internet requests.
I use the following Rijndael code to do encryption without fail for many times. But why it can not encrypt an ISO file with 4.2 GB? In fact my computer has 16GB memory and it should not be a memory problem. I use Windows 7 Ultimate. The code is compiled as winform (.Net 4) using Visual Studio 2010 (a VB.NET project).
I have checked that the ISO file is OK and can be mounted as virtual drive and even can be burnt to DVD rom. So it is not the ISO file problem.My question: Why the following code cannot encrypt an ISO file with size of 4.2GB? Is that caused by the limitation of Windows/.NET 4 implementation?
What I've decided to start working on is pretty much a personal project but something I may use in my UNI course in due time. I'm creating a security program with a set of access codes (yes I am a bit of a star trek fan) - 4 in total to be exact. I want to be able to use an Encrypted key file in form of a simple notepad created text file to update the codes at any due time. All I'm looking to do is write the access codes to the text file (say for a friend to use the program), Encrypt the file through the program and be able to also decrypt to obtain the new access codes on demand also via the same program. Once decrypted the codes can be read and verified if the user has entered each one correctly. I could hard code the access codes into the program but would rather do it the way I've thought of.
Back in the days of the old VB6 there was a simple method but for some reason that doesnt work any more. What I guess I'm looking to do is have 4 text fields where 4 digit access codes are typed into, have the program take them and encrypt each one is then written to the text file. Hoping that will make it a bit clearer what I'm trying to achieve as I think I made it sound like I want to encrypt the text file after the info has been written to it, which is of course one option so wouldn't mind know how to do that too!
I'm working on a basic file encryption by using the Imports System.Security.Cryptography.I was thinking of putting a password as a final security measure.Would i have to store the password inside the file or how will this work?
I recently changed application settings to be in an encrypted config file.The first time I run any application and try to retrieve a setting (My.settings. ...) from the config file I get an Unrecognized attribute 'configProtectionProvider'If I restart the application I don't get an error due to the fact that it doesn't re-encrypt during that run. Why when I run the application for the first time am I getting this error?
I am encrypting the config file on application startup using the following code:
I recently made a simple pseudo-encryption program that changes each character into another. It is capable of encrypting and decrypting a string. This can also be done to any text file as well. The characters range from ASCII 32-254 (This on it's own may be an issue because of #127 being DEL).
Because I believed my own coding may be at fault, I attempted this with Triple Des with identical results.For Triple Des, the requirements for en/decryption was:
Encrypt: String to Byte Decrypt: Byte to String
And to change them either direction, I used UTF8. I also attempted ASCII and UTF32, but I don't know what I should do. I am considering dropping this but I want to learn problems like this because I am currently in college and haven't started my core classes for programming yet and want the head start.
The point where I have come into a problem is attempting to do this to another file type like an image. I looked at the results from encrypting then decrypting and the results were similar, but it seems file encoding must be the culprit.
am writing the pgm using vb.net to get the file from reomte machine & store it on local machine using FTP . but am always getting an error like "remote machine returned an error :(550) file un avaliable (e.g , file not found, no access)
Dim reqFTP As FtpWebRequest Dim filepath As String Dim filename As String Dim filename1 As String
I wrote some code to share files throughout my network. The thing is that i don't understand how to determine how much the client has sent already and how much is left. I have posted my code below so you guys can see what I'm talking about.[code]...
I need to transfer files from one server to multiple cients (using the internet) in the fastest possible way in .NET . What are the different types of transfer protocols which can be used in .NET or VB.NET so that the files are sent in a very short time ? I have tried using FTP, but that is slow because it requires authentication, handshaking etc. What i want to know is the options which we have in .NET for sending files in the fastest possible way between a server and multiple clients.
I am writing a program in vb.net 2008 and need to be able to send and receive files using Zmodem through the a comport. I have search the net and have not found much to do with Zmodem in VB.net. I am already using the System.IO.Ports.SerialPort to send and receive commands through the comport but how to send or receive a file using the Zmodem protocol.
I want to transfer a file from one computer to another computer by giving the port number and IP address. There will be an other software waiting for the file to be received.
Basically I want to take My Client.Then for example Lets say in my client I have "A = 1" Then my 2nd file which has random data in it.So Client= My Client File = The File which I want in the end result
How could I Inject "A = TextBox1.Text" from Client to File.I heard it's called "End Of File" or something like that.
