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diff --git a/src/DotNetOAuth/Messaging/Bindings/StandardReplayProtectionBindingElement.cs b/src/DotNetOAuth/Messaging/Bindings/StandardReplayProtectionBindingElement.cs
new file mode 100644
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+++ b/src/DotNetOAuth/Messaging/Bindings/StandardReplayProtectionBindingElement.cs
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+//-----------------------------------------------------------------------
+// <copyright file="StandardReplayProtectionBindingElement.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOAuth.Messaging.Bindings {
+	using System;
+	using System.Diagnostics;
+
+	/// <summary>
+	/// A binding element that checks/verifies a nonce message part.
+	/// </summary>
+	internal class StandardReplayProtectionBindingElement : IChannelBindingElement {
+		/// <summary>
+		/// These are the characters that may be chosen from when forming a random nonce.
+		/// </summary>
+		private const string AllowedCharacters = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+
+		/// <summary>
+		/// The persistent store for nonces received.
+		/// </summary>
+		private INonceStore nonceStore;
+
+		/// <summary>
+		/// The length of generated nonces.
+		/// </summary>
+		private int nonceLength = 8;
+
+		/// <summary>
+		/// A random number generator.
+		/// </summary>
+		private Random generator = new Random();
+
+		/// <summary>
+		/// Initializes a new instance of the <see cref="StandardReplayProtectionBindingElement"/> class.
+		/// </summary>
+		/// <param name="nonceStore">The store where nonces will be persisted and checked.</param>
+		internal StandardReplayProtectionBindingElement(INonceStore nonceStore) {
+			if (nonceStore == null) {
+				throw new ArgumentNullException("nonceStore");
+			}
+
+			this.nonceStore = nonceStore;
+		}
+
+		#region IChannelBindingElement Properties
+
+		/// <summary>
+		/// Gets the protection that this binding element provides messages.
+		/// </summary>
+		public MessageProtection Protection {
+			get { return MessageProtection.ReplayProtection; }
+		}
+
+		#endregion
+
+		/// <summary>
+		/// Gets or sets the strength of the nonce, which is measured by the number of
+		/// nonces that could theoretically be generated.
+		/// </summary>
+		/// <remarks>
+		/// The strength of the nonce is equal to the number of characters that might appear
+		/// in the nonce to the power of the length of the nonce.
+		/// </remarks>
+		internal double NonceStrength {
+			get {
+				return Math.Pow(AllowedCharacters.Length, this.nonceLength);
+			}
+
+			set {
+				value = Math.Max(value, AllowedCharacters.Length);
+				this.nonceLength = (int)Math.Log(value, AllowedCharacters.Length);
+				Debug.Assert(this.nonceLength > 0, "Nonce length calculated to be below 1!");
+			}
+		}
+
+		#region IChannelBindingElement Methods
+
+		/// <summary>
+		/// Applies a nonce to the message.
+		/// </summary>
+		/// <param name="message">The message to apply replay protection to.</param>
+		/// <returns>True if the message protection was applied.  False otherwise.</returns>
+		public bool PrepareMessageForSending(IProtocolMessage message) {
+			IReplayProtectedProtocolMessage nonceMessage = message as IReplayProtectedProtocolMessage;
+			if (nonceMessage != null) {
+				nonceMessage.Nonce = this.GenerateUniqueFragment();
+				return true;
+			}
+
+			return false;
+		}
+
+		/// <summary>
+		/// Verifies that the nonce in an incoming message has not been seen before.
+		/// </summary>
+		/// <param name="message">The incoming message.</param>
+		/// <returns>
+		/// True if the message nonce passed replay detection checks.
+		/// False if the message did not have a nonce that could be checked at all.
+		/// </returns>
+		/// <exception cref="ReplayedMessageException">Thrown when the nonce check revealed a replayed message.</exception>
+		public bool PrepareMessageForReceiving(IProtocolMessage message) {
+			IReplayProtectedProtocolMessage nonceMessage = message as IReplayProtectedProtocolMessage;
+			if (nonceMessage != null) {
+				if (nonceMessage.Nonce == null || nonceMessage.Nonce.Length <= 0) {
+					throw new ProtocolException(MessagingStrings.InvalidNonceReceived);
+				}
+
+				if (!this.nonceStore.StoreNonce(nonceMessage.Nonce, nonceMessage.UtcCreationDate)) {
+					throw new ReplayedMessageException(message);
+				}
+
+				return true;
+			}
+
+			return false;
+		}
+
+		#endregion
+
+		/// <summary>
+		/// Generates a string of random characters for use as a nonce.
+		/// </summary>
+		/// <returns>The nonce string.</returns>
+		private string GenerateUniqueFragment() {
+			char[] nonce = new char[this.nonceLength];
+			for (int i = 0; i < nonce.Length; i++) {
+				nonce[i] = AllowedCharacters[this.generator.Next(AllowedCharacters.Length)];
+			}
+			return new string(nonce);
+		}
+	}
+}