guid

If you use a GUID as a password for a publicly facing application as a means to gain access to a service, is this security through obscurity? I think the obvious answer is yes, but the level of security seems very high to me since the chances of guessing a GUID is very very low correct? Update The GUID will be stored in a device, when plugged in, will send over the GUID via SSL connection. Maybe I could generate a GUID, then do a AES 128 bit encrption on the GUID and store that value on the device? In my opinion, the answer is no. If you set a password to be a newly created GUID, then it is a

how can i generate 16 digit unique random numbers without any repetition in c# asp.net, as i have read the concept of GUID which generate characters along with numbers but i don't want characters kindly suggest is there any way to acheive it You can create a random number using the Random class: private static Random RNG = new Random(); public string Create16DigitString() { var builder = new StringBuilder(); while (builder.Length < 16) { builder.Append(RNG.Next(10).ToString()); } return builder.ToString(); } Ensuring that there are no collisions requires you to track all results that you have

Possible Duplicate: Is a GUID unique 100% of the time? After reading all posts on Guid, still I am unclear about one simple thing: Guids generated by different machines also maintain their Uniqueness or not. I have read about guid uniqueness on single machine,but I still don't know about uniqueness with different machines Tilak GUID are "practically" universally unique. A GUID is a 128-bit integer (16 bytes) that can be used across all computers and networks wherever a unique identifier is required. Such an identifier has a very low probability of being duplicated. From the MSDN It is

I am thinking to use a GUID in my .net app which uses SQL Server. Should I be writing a stored procedure which generates the GUID on each record entered or should I be directly generating it from the application. Reasons for asking the question (If am wrong correct me in this): I (as/pre)sume: When generating the GUID from the database, you can assume that the DB remembers the previous generated GUID where as the application remembering it is difficult. SQL Server has the creation of GUID's built in. There is no need to write a separate stored procedure for this. You can use NEWID()

I want to create a cryptographically secure GUID (v4) in .NET. .NET's Guid.NewGuid() function is not cryptographically secure, but .NET does provide the System.Security.Cryptography.RNGCryptoServiceProvider class. I would like to be able to pass a random number function as a delegate to Guid.NewGuid (or even pass some class that provides a generator interface) but it doesn't look as though that is possible with the default implementation. Can I create a cryptographically secure GUID by using System.GUID and System.Security.Cryptography.RNGCryptoServiceProvider together? Yes you can, Guid

Is there a command line tool for Unix and Windows that uses the same algorithm to create GUIDs for both platforms? 'e2fsprogs' project maintain uuidgen utility. http://e2fsprogs.sourceforge.net/ It is already available on any Linux/BSD* distros. For Windows I recommend install Cygwin, 'e2fsprogs' package available from there! As report j4y this utility is available under MAC OS. Just run: $ uuidgen -r # random based UUID/GUID $ uuidgen -t # time based UUID/GUID I don't know if there is a command line tool available, but you could simply write one in C# (it should run with Mono): class Program