diff --git a/rosapi/src/rosapi/params.py b/rosapi/src/rosapi/params.py
index 20c79c35d..3af991ebc 100644
--- a/rosapi/src/rosapi/params.py
+++ b/rosapi/src/rosapi/params.py
@@ -39,7 +39,7 @@
 from rcl_interfaces.srv import GetParameters, ListParameters, SetParameters
 from rclpy.callback_groups import MutuallyExclusiveCallbackGroup
 from rclpy.node import Node
-from rclpy.parameter import get_parameter_value
+from rclpy.parameter import Parameter
 from rclpy.task import Future
 from ros2node.api import get_absolute_node_name
 from rosapi.async_helper import futures_wait_for
diff --git a/rosbridge_library/src/rosbridge_library/capabilities/subscribe.py b/rosbridge_library/src/rosbridge_library/capabilities/subscribe.py
index 0f523ab22..1aab0ed5a 100644
--- a/rosbridge_library/src/rosbridge_library/capabilities/subscribe.py
+++ b/rosbridge_library/src/rosbridge_library/capabilities/subscribe.py
@@ -31,6 +31,7 @@
 # POSSIBILITY OF SUCH DAMAGE.
 
 import fnmatch
+import uuid
 from functools import partial
 from threading import Lock
 
@@ -110,6 +111,19 @@ def subscribe(
         compression is to be used (current valid values are 'png')
 
         """
+        if sid is None:
+            self.protocol.log(
+                "WARNING: subscribe called with no subscription id, "
+                + "this is not supported by ROSBridge"
+            )
+            sid = uuid.uuid4()
+
+        if sid in self.clients:
+            self.protocol.log(
+                "WARNING: subscribe called with existing subscription id, "
+                + "this is not supported by ROSBridge"
+            )
+            sid = uuid.uuid4()
 
         client_details = {
             "throttle_rate": throttle_rate,
@@ -307,27 +321,34 @@ def publish(self, topic, message, fragment_size=None, compression="none"):
         'png' and 'none'
 
         """
-        # TODO: fragmentation, proper ids
-
-        outgoing_msg = {"op": "publish", "topic": topic}
-        if compression == "png":
-            outgoing_msg["msg"] = message.get_json_values()
-            outgoing_msg_dumped = encode_json(outgoing_msg)
-            outgoing_msg = {"op": "png", "data": encode_png(outgoing_msg_dumped)}
-        elif compression == "cbor":
-            outgoing_msg = message.get_cbor(outgoing_msg)
-        elif compression == "cbor-raw":
-            (secs, nsecs) = self.protocol.node_handle.get_clock().now().seconds_nanoseconds()
-            outgoing_msg["msg"] = {
-                "secs": secs,
-                "nsecs": nsecs,
-                "bytes": message.message,
-            }
-            outgoing_msg = message.get_cbor_raw(outgoing_msg)
-        else:
-            outgoing_msg["msg"] = message.get_json_values()
 
-        self.protocol.send(outgoing_msg, compression=compression)
+        subscription = self._subscriptions.get(topic)
+        if subscription:
+            for sid in subscription.clients:
+                outgoing_msg = {"op": "publish", "topic": topic, "id": sid}
+                if compression == "png":
+                    outgoing_msg["msg"] = message.get_json_values()
+                    outgoing_msg_dumped = encode_json(outgoing_msg)
+                    outgoing_msg = {"op": "png", "data": encode_png(outgoing_msg_dumped), "id": sid}
+                elif compression == "cbor":
+                    outgoing_msg["id"] = sid
+                    outgoing_msg = message.get_cbor(outgoing_msg)
+                elif compression == "cbor-raw":
+                    (secs, nsecs) = (
+                        self.protocol.node_handle.get_clock().now().seconds_nanoseconds()
+                    )
+                    outgoing_msg["msg"] = {
+                        "secs": secs,
+                        "nsecs": nsecs,
+                        "bytes": message.message,
+                    }
+                    outgoing_msg["id"] = sid
+                    outgoing_msg = message.get_cbor_raw(outgoing_msg)
+                else:
+                    outgoing_msg["msg"] = message.get_json_values()
+                    outgoing_msg["id"] = sid
+
+                self.protocol.send(outgoing_msg, compression=compression)
 
     def finish(self):
         for subscription in self._subscriptions.values():