diff --git a/src/backend/marsha/settings.py b/src/backend/marsha/settings.py
index 97655bbd74..df24cf01df 100644
--- a/src/backend/marsha/settings.py
+++ b/src/backend/marsha/settings.py
@@ -171,7 +171,7 @@ class Base(Configuration):
     # }
     CHANNEL_LAYERS = {
         "default": {
-            "BACKEND": "channels_redis.core.RedisChannelLayer",
+            "BACKEND": "marsha.websocket.layers.JsonRedisChannelLayer",
             "CONFIG": {
                 "hosts": values.ListValue(
                     [("redis", 6379)], environ_name="REDIS_HOST", environ_prefix=None
diff --git a/src/backend/marsha/websocket/layers.py b/src/backend/marsha/websocket/layers.py
new file mode 100644
index 0000000000..855886ef66
--- /dev/null
+++ b/src/backend/marsha/websocket/layers.py
@@ -0,0 +1,36 @@
+"""Layers used by django channels"""
+import json
+import random
+
+from django.core.serializers.json import DjangoJSONEncoder
+
+from channels_redis.core import RedisChannelLayer
+
+
+class JsonRedisChannelLayer(RedisChannelLayer):
+    """Use json to serialize and deserialize messages."""
+
+    def serialize(self, message):
+        """
+        Serializes message in json.
+        """
+        value = bytes(json.dumps(message, cls=DjangoJSONEncoder), encoding="utf-8")
+        if self.crypter:
+            value = self.crypter.encrypt(value)
+
+        # As we use an sorted set to expire messages we need to guarantee uniqueness,
+        # with 12 bytes.
+        random_prefix = random.getrandbits(8 * 12).to_bytes(12, "big")
+        return random_prefix + value
+
+    def deserialize(self, message):
+        """
+        Deserializes from a byte string.
+        """
+        # Removes the random prefix
+        message = message[12:]
+        message = message.decode("utf-8")
+
+        if self.crypter:
+            message = self.crypter.decrypt(message, self.expiry + 10)
+        return json.loads(message)
diff --git a/src/backend/marsha/websocket/tests/test_layers.py b/src/backend/marsha/websocket/tests/test_layers.py
new file mode 100644
index 0000000000..0373793081
--- /dev/null
+++ b/src/backend/marsha/websocket/tests/test_layers.py
@@ -0,0 +1,31 @@
+"""Test marsha layers use by django channels."""
+from django.test import TestCase
+
+from marsha.websocket.layers import JsonRedisChannelLayer
+
+
+class JsonRedisChannelLayerTest(TestCase):
+    """Test serialize and deserialize."""
+
+    def test_serialize_message(self):
+        """
+        Test default serialization method
+        """
+        message = {"a": True, "b": None, "c": {"d": []}}
+        channel_layer = JsonRedisChannelLayer()
+        serialized = channel_layer.serialize(message)
+        self.assertIsInstance(serialized, bytes)
+        self.assertEqual(serialized[12:], b'{"a": true, "b": null, "c": {"d": []}}')
+
+    def test_deserialize_message(self):
+        """
+        Test default deserialization method
+        """
+        message = (
+            b'[\x85\xf8\xdeY\xe5\xa3}is\x0f3{"a": true, "b": null, "c": {"d": []}}'
+        )
+        channel_layer = JsonRedisChannelLayer()
+        deserialized = channel_layer.deserialize(message)
+
+        self.assertIsInstance(deserialized, dict)
+        self.assertEqual(deserialized, {"a": True, "b": None, "c": {"d": []}})