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diff --git a/src/lib/hooks/callout_handle_associate.h b/src/lib/hooks/callout_handle_associate.h
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+// Copyright (C) 2018-2022 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef CALLOUT_HANDLE_ASSOCIATE_H
+#define CALLOUT_HANDLE_ASSOCIATE_H
+
+#include <hooks/callout_handle.h>
+
+namespace isc {
+namespace hooks {
+
+/// @brief Base class for classes which need to be associated with
+/// a @c CalloutHandle object.
+///
+/// The @c CalloutHandle is an object used to pass various parameters
+/// between Kea and the callouts. The Kea servers usually invoke
+/// multiple different callouts for a single packet such as DHCP
+/// packet, control command etc. Therefore, it is required to
+/// associate this packet with an instance of the callout handle, so
+/// this instance can be used for all callouts invoked for this
+/// packet.
+///
+/// Previously this association was made by the @c CalloutHandleStore
+/// class. However, with the introduction of parallel processing
+/// of packets (DHCP packets parking) it became awkward to use.
+/// Attempts to extend this class to hold a map of associations
+/// failed because of no easy way to garbage collect unused handles.
+///
+/// The easiest way to deal with this is to provide ownership of the
+/// @c CalloutHandle to the object with which it is associated. The
+/// class of this object needs to derive from this class. When the
+/// object (e.g. DHCP packet) goes out of scope and is destroyed
+/// this instance is destroyed as well.
+class CalloutHandleAssociate {
+public:
+
+    /// @brief Constructor.
+    CalloutHandleAssociate();
+
+    /// @brief Returns callout handle.
+    ///
+    /// The callout handle is created if it doesn't exist. Subsequent
+    /// calls to this method always return the same handle.
+    ///
+    /// @return Pointer to the callout handle.
+    CalloutHandlePtr getCalloutHandle();
+
+    /// @brief Reset callout handle.
+    void resetCalloutHandle();
+
+protected:
+
+    /// @brief Callout handle stored.
+    CalloutHandlePtr callout_handle_;
+};
+
+} // end of isc::hooks
+} // end of isc
+
+#endif