From 9f3d15a7bdf3487535c2565817ee704cf7cb0486 Mon Sep 17 00:00:00 2001
From: Ernst Klamer <e.klamer@gmail.com>
Date: Tue, 10 Oct 2023 19:35:04 +0200
Subject: [PATCH] Add better explanation for the counter in encrypted messages

---
 src/encryption.html | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/encryption.html b/src/encryption.html
index c993f63..71f4b33 100644
--- a/src/encryption.html
+++ b/src/encryption.html
@@ -50,8 +50,12 @@ <h3 id="input">The input</h3>
   <code>231d39c1d7cc1ab1aee224cd096db932</code>.
 </p>
 <p>
-  We also need a <strong>Counter</strong>, which is a 4 bytes long value, which
-  is changed every advertisement. Let's take <code>0x00112233</code> as example.
+  We also need a <strong>Counter</strong>, which is a 4 bytes long value (unsigned
+  32-bit little-endian integer), which should increase every advertisement. This
+  counter can be used to implement the replay protection features of AES-CCM, but has
+  to be implemented on the receiving side (e.g. by verifying that the counter has increased
+  compared to the previous counter value).
+  In the example we use <code>0x00112233</code> as value for the counter.
 </p>
 <p>
   Last thing we need is the <strong>MAC address</strong> of the sensor device,