LUID - Locally unique identifier

Luid.cs

using System.Security.Cryptography;
using System.Text;

namespace TrotenLib
{
    /// <summary>
    /// Generate unique-enough pseudo-random identifiers where GUID is for some reason unsuitable
    /// Explanation:  https://stackoverflow.com/a/37099588/243557
    /// </summary>
    public static class LUID
    {
        private static readonly RNGCryptoServiceProvider RandomGenerator = new RNGCryptoServiceProvider();
        private static readonly char[] ValidCharacters = "ABCDEFGHJKLMNPQRSTUVWXYZ23456789".ToCharArray();
        public const int DefaultLength = 6;
        private static int counter = 0;

        public static string Generate(int length = DefaultLength)
        {
            var randomData = new byte[length];
            RandomGenerator.GetNonZeroBytes(randomData);

            var result = new StringBuilder(DefaultLength);
            foreach (var value in randomData)
            {
                counter = (counter + value) % (ValidCharacters.Length - 1);
                result.Append(ValidCharacters[counter]);
            }
            return result.ToString();
        }
    }
}