Index: uspace/lib/hound/src/client.c
===================================================================
--- uspace/lib/hound/src/client.c	(revision fe0b448b9aa3eff83c270c507c2e31d0eadbded9)
+++ uspace/lib/hound/src/client.c	(revision 059490c27c5feac3ad2bd31ed3a86c9aaa9eee97)
@@ -43,7 +43,5 @@
 
 #include "client.h"
-#include "server.h"
-
-static const char *HOUND_SERVICE = "audio/hound";
+#include "protocol.h"
 
 /***
@@ -57,5 +55,5 @@
 
 typedef struct hound_context {
-	async_sess_t *session;
+	hound_sess_t *session;
 	const char *name;
 	bool record;
@@ -71,19 +69,4 @@
 } hound_context_t;
 
-async_sess_t *hound_get_session(void)
-{
-	service_id_t id = 0;
-	const int ret =
-	    loc_service_get_id(HOUND_SERVICE, &id, IPC_FLAG_BLOCKING);
-	if (ret != EOK)
-		return NULL;
-	return loc_service_connect(EXCHANGE_SERIALIZE, id, IPC_FLAG_BLOCKING);
-}
-
-void hound_release_session(async_sess_t *sess)
-{
-	if (sess)
-		async_hangup(sess);
-}
 
 static hound_context_t *hound_context_create(const char *name, bool record,
@@ -101,5 +84,5 @@
 		new_context->name = cont_name;
 		new_context->record = record;
-		new_context->session = hound_get_session();
+		new_context->session = hound_service_connect(HOUND_SERVICE);
 		new_context->main_stream = NULL;
 		new_context->main_format.sample = format;
Index: uspace/lib/hound/src/protocol.c
===================================================================
--- uspace/lib/hound/src/protocol.c	(revision fe0b448b9aa3eff83c270c507c2e31d0eadbded9)
+++ uspace/lib/hound/src/protocol.c	(revision 059490c27c5feac3ad2bd31ed3a86c9aaa9eee97)
@@ -42,8 +42,25 @@
 #include <libarch/types.h>
 
+#include "protocol.h"
 #include "client.h"
 #include "server.h"
 
-static const char *HOUND_SERVICE = "audio/hound";
+const char *HOUND_SERVICE = "audio/hound";
+
+hound_sess_t *hound_service_connect(const char *service)
+{
+	service_id_t id = 0;
+	const int ret =
+	    loc_service_get_id(service, &id, IPC_FLAG_BLOCKING);
+	if (ret != EOK)
+		return NULL;
+	return loc_service_connect(EXCHANGE_PARALLEL, id, IPC_FLAG_BLOCKING);
+}
+
+void hound_service_disconnect(hound_sess_t *sess)
+{
+	if (sess)
+		async_hangup(sess);
+}
 
 /***
@@ -55,4 +72,14 @@
 	void *arg;
 } callback_t;
+
+hound_sess_t *hound_get_session(void)
+{
+	return hound_service_connect(HOUND_SERVICE);
+}
+
+void hound_release_session(hound_sess_t *sess)
+{
+	hound_service_disconnect(sess);
+}
 
 
Index: uspace/lib/hound/src/protocol.h
===================================================================
--- uspace/lib/hound/src/protocol.h	(revision 059490c27c5feac3ad2bd31ed3a86c9aaa9eee97)
+++ uspace/lib/hound/src/protocol.h	(revision 059490c27c5feac3ad2bd31ed3a86c9aaa9eee97)
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2013 Jan Vesely
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+/** @addtogroup libhound
+ * @addtogroup audio
+ * @{
+ */
+/** @file
+ * @brief Audio PCM buffer interface.
+ */
+
+#ifndef LIBHOUND_PROTOCOL_H_
+#define LIBHOUND_PROTOCOL_H_
+
+#include <async.h>
+#include <pcm/format.h>
+
+const char *HOUND_SERVICE;
+
+typedef async_sess_t hound_sess_t;
+typedef int hound_context_id_t;
+typedef int hound_stream_id_t;
+
+hound_sess_t *hound_service_connect(const char *service);
+void hound_service_disconnect(hound_sess_t *sess);
+
+hound_context_id_t hound_service_register_context(hound_sess_t *sess,
+    const char *name);
+int hound_service_unregister_context(hound_sess_t *sess);
+
+hound_stream_id_t hound_service_stream_add(hound_sess_t *sess, int flags,
+    pcm_format_t format, size_t bsize);
+int hound_service_stream_remove(hound_sess_t *sess, hound_stream_id_t);
+int hound_service_stream_drain(hound_sess_t *sess, hound_stream_id_t);
+
+int hound_service_stream_write(async_exch_t *exch, hound_stream_id_t,
+    const void *data, size_t size);
+int hound_service_stream_read(async_exch_t *exch, hound_stream_id_t,
+    void *data, size_t size);
+
+
+#endif
+/** @}
+ */