diff --git a/lib/communication.c b/lib/communication.c
index 1976b41..bd171f5 100644
--- a/lib/communication.c
+++ b/lib/communication.c
@@ -25,54 +25,50 @@ int file_close (FILE *f)
     return 0;
 }
 
-// SERVICE
-
-int srv_path (char *buf, const char *sname)
+void srv_init (struct service *srv, const char *sname)
 {
-    if (buf == NULL) {
-        return 1;
-    }
+    if (srv == NULL)
+        return;
 
-    // already done in mkfifo
-    if (strlen(TMPDIR) + strlen(sname) > PATH_MAX) {
-        return 2;
-    }
+    // gets the service path, such as /tmp/<service>
+    bzero (srv->spath, PATH_MAX);
+    strncat (srv->spath, TMPDIR, PATH_MAX);
+    strncat (srv->spath, sname, PATH_MAX);
 
-    bzero (buf, PATH_MAX);
-    strncat (buf, TMPDIR, PATH_MAX);
-    strncat (buf, sname, PATH_MAX);
-
-    return 0;
+    srv->version = COMMUNICATION_VERSION;
+    srv->index = 0; // TODO
 }
 
-int srv_create (const char *fifopath)
+// SERVICE
+
+int srv_create (struct service *srv)
 {
     int ret;
-    if ((ret = mkfifo (fifopath, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH))) {
+    if ((ret = mkfifo (srv->spath, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH))) {
         switch (errno) {
             case EACCES :
-                printf ("file %s : EACCES\n", fifopath);
+                printf ("file %s : EACCES\n", srv->spath);
                 return 1;
             case EEXIST :
-                printf ("file %s : EEXIST\n", fifopath);
+                printf ("file %s : EEXIST\n", srv->spath);
                 break;
             case ENAMETOOLONG :
-                printf ("file %s : ENAMETOOLONG\n", fifopath);
+                printf ("file %s : ENAMETOOLONG\n", srv->spath);
                 return 2;
             case ENOENT :
-                printf ("file %s : ENOENT\n", fifopath);
+                printf ("file %s : ENOENT\n", srv->spath);
                 return 3;
             case ENOSPC :
-                printf ("file %s : ENOSPC\n", fifopath);
+                printf ("file %s : ENOSPC\n", srv->spath);
                 return 4;
             case ENOTDIR :
-                printf ("file %s : ENOTDIR\n", fifopath);
+                printf ("file %s : ENOTDIR\n", srv->spath);
                 return 5;
             case EROFS :
-                printf ("file %s : EROFS\n", fifopath);
+                printf ("file %s : EROFS\n", srv->spath);
                 return 6;
             default :
-                printf ("err file %s unknown\n", fifopath);
+                printf ("err file %s unknown\n", srv->spath);
                 return 7;
         }
     }
@@ -80,18 +76,18 @@ int srv_create (const char *fifopath)
     return 0;
 }
 
-int srv_close (const char *fifopath)
+int srv_close (struct service *srv)
 {
-    if (unlink (fifopath)) {
+    if (unlink (srv->spath)) {
         return 1;
     }
 
     return 0;
 }
 
-int srv_get_new_process (struct process *p, const char * spath)
+int srv_get_new_process (struct process *p, const struct service *srv)
 {
-    if (spath == NULL) {
+    if (srv->spath == NULL) {
         return -1;
     }
 
@@ -102,7 +98,7 @@ int srv_get_new_process (struct process *p, const char * spath)
     struct timespec ts = { 0 };
     struct timespec ts2 = { 0 };
 
-    FILE * f = fopen (spath, "r");
+    FILE * f = fopen (srv->spath, "r");
     clock_gettime(CLOCK_REALTIME, &ts);
     fgets (buf, BUFSIZ, f);
     clock_gettime(CLOCK_REALTIME, &ts2);
diff --git a/lib/communication.h b/lib/communication.h
index ebe062e..2234c96 100644
--- a/lib/communication.h
+++ b/lib/communication.h
@@ -19,11 +19,13 @@
 struct service {
     unsigned int version;
     unsigned int index;
+    char spath[PATH_MAX];
+    FILE *spipe;
 };
 
-int srv_path (char *buf, const char *sname);
+void srv_init (struct service *srv, const char *sname);
 
-int srv_get_new_process (struct process *proc, const char * spath);
+int srv_get_new_process (struct process *proc, const struct service *srv);
 
 /*
  * returns
@@ -32,8 +34,8 @@ int srv_get_new_process (struct process *proc, const char * spath);
  *  2 : service name too long
  *  3 : unable to create fifo
  */
-int srv_create (const char *sname);
-int srv_close (const char *sname);
+int srv_create (struct service *srv);
+int srv_close (struct service *srv);
 
 int srv_read (struct process *, void * buf, size_t *);
 int srv_write (struct process *, void * buf, size_t);
diff --git a/lib/communication.o b/lib/communication.o
deleted file mode 100644
index 967d37e..0000000
Binary files a/lib/communication.o and /dev/null differ
diff --git a/lib/process.h b/lib/process.h
index 13461fd..a4a3dbd 100644
--- a/lib/process.h
+++ b/lib/process.h
@@ -23,6 +23,7 @@ struct process {
 };
 
 struct process * srv_process_copy (const struct process *p);
+void srv_process_free (struct process * p);
 
 int srv_process_eq (const struct process *p1, const struct process *p2);
 
diff --git a/lib/pubsubd.c b/lib/pubsubd.c
new file mode 100644
index 0000000..55d8db1
--- /dev/null
+++ b/lib/pubsubd.c
@@ -0,0 +1,190 @@
+#include "pubsubd.h"
+#include <stdlib.h>
+
+void
+ohshit(int rvalue, const char* str) {
+    fprintf(stderr, "%s\n", str);
+    exit(rvalue);
+}
+
+// CHANNELS
+
+void pubsubd_channels_init (struct channels *chans) { LIST_INIT(chans); }
+
+void
+pubsubd_channels_add (struct channels *chans, struct channel *c)
+{
+    if(!chans || !c)
+        return;
+
+    struct channel *n = pubsubd_channel_copy (c);
+    LIST_INSERT_HEAD(chans, n, entries);
+}
+
+void
+pubsubd_channels_del (struct channels *chans, struct channel *c)
+{
+    struct channel *todel = pubsubd_channel_get (chans, c);
+    if(todel != NULL) {
+        LIST_REMOVE(todel, entries);
+        srv_process_free (todel);
+        free (todel);
+        todel = NULL;
+    }
+}
+
+struct channel * pubsubd_channel_copy (struct channel *c)
+{
+    struct channel *copy;
+    copy = malloc (sizeof(struct channel));
+    memcpy (copy, c, sizeof(struct channel));
+    return copy;
+}
+
+struct channel * pubsubd_channel_get (struct channels *chans, struct channel *c)
+{
+    struct channel * np = NULL;
+    LIST_FOREACH(np, chans, entries) {
+        if (pubsubd_channels_eq (np, c))
+            return np;
+    }
+    return NULL;
+}
+
+int
+pubsubd_channels_eq (const struct channel *c1, const struct channel *c2)
+{
+    return (strncmp (c1->chan, c2->chan, c1->chanlen) == 0);
+}
+
+// SUBSCRIBER
+
+void pubsubd_subscriber_init (struct app_list_head *chans) { LIST_INIT(chans); } 
+
+struct app_list_elm * pubsubd_app_list_elm_copy (struct app_list_elm *ale)
+{
+    if (ale == NULL)
+        return NULL;
+
+    struct app_list_elm * n;
+    n = malloc (sizeof (struct app_list_elm));
+
+    n->p = srv_process_copy(ale->p);
+
+    return n;
+}
+
+void
+pubsubd_subscriber_add (struct app_list_head *alh, struct app_list_elm *ale)
+{
+    if(!alh || !ale)
+        return;
+
+    struct app_list_elm *n = pubsubd_app_list_elm_copy (ale);
+    LIST_INSERT_HEAD(alh, n, entries);
+}
+
+struct app_list_elm *
+pubsubd_subscriber_get (const struct app_list_head *chans, const struct app_list_elm *p)
+{
+    struct app_list_elm *np, *res = NULL;
+    LIST_FOREACH(np, chans, entries) {
+        if(srv_process_eq (np, p)) {
+            res = np;
+        }
+    }
+    return res;
+}
+
+void
+pubsubd_subscriber_del (struct app_list_head *chans, struct app_list_elm *p)
+{
+    struct app_list_elm *todel = pubsubd_subscriber_get (chans, p);
+    if(todel != NULL) {
+        LIST_REMOVE(todel, entries);
+        pubsubd_app_list_elm_free (todel);
+        free (todel);
+        todel = NULL;
+    }
+}
+
+void pubsubd_app_list_elm_create (struct app_list_elm *ale, struct process *p)
+{
+    if (ale == NULL)
+        return;
+
+    ale->p = srv_process_copy (p);
+}
+
+void pubsubd_app_list_elm_free (struct app_list_elm *todel)
+{
+    if (todel == NULL)
+        return NULL;
+    srv_process_free (todel->p);
+}
+
+// MESSAGE, TODO CBOR
+
+void pubsubd_msg_serialize (const struct pubsub_msg *msg, char **data, size_t *len)
+{
+    if (msg == NULL || data == NULL || len == NULL)
+        return;
+
+    // msg: "type(1) chanlen(8) chan datalen(8) data
+    *len = 1 + sizeof(size_t) + msg->chanlen + sizeof(size_t) + msg->datalen;
+    *data = malloc(*len);
+
+    size_t i = 0;
+
+    data[0][i] = msg->type;                             i++;
+    memcpy (data[0][i], msg->chanlen, sizeof(size_t));   i += sizeof(size_t);
+    memcpy (data[0][i], msg->chan, msg->chanlen);        i += msg->chanlen;
+    memcpy (data[0][i], msg->datalen, sizeof(size_t));   i += sizeof(size_t);
+    memcpy (data[0][i], msg->data, msg->datalen);        i += msg->datalen;
+}
+
+void pubsubd_msg_unserialize (struct pubsub_msg *msg, const char *data, size_t len)
+{
+    if (msg == NULL || data == NULL)
+        return;
+
+    size_t i = 0;
+    msg->type = data[0][i];                             i++;
+    memcpy (&msg->chanlen, data + i, sizeof(size_t));   i += sizeof(size_t);
+    msg->chan = malloc (msg->chanlen);
+    memcpy (msg->chan, data + i, msg->chanlen);         i += msg->chanlen;
+    memcpy (&msg->datalen, data + i, sizeof(size_t));   i += sizeof(size_t);
+    msg->data = malloc (msg->datalen);
+    memcpy (msg->data, data + i, msg->datalen);         i += msg->datalen;
+}
+
+void pubsubd_msg_free (struct pubsub_msg *msg)
+{
+    if (msg->chan) {
+        free (msg->chan);
+        msg->chan = 0;
+    }
+    if (msg->data) {
+        free (msg->data);
+        msg->data = 0;
+    }
+}
+
+// COMMUNICATION
+
+void pubsubd_msg_send (struct service *s, struct pubsub_msg * m, struct process *p)
+{
+}
+void pubsubd_msg_recv (struct service *s, struct pubsub_msg * m, struct process *p)
+{
+}
+void pubsub_msg_send (struct service *s, struct pubsub_msg * m)
+{
+}
+void pubsub_msg_recv (struct service *s, struct pubsub_msg * m)
+{
+}
+
+// SERVICE
+
+void pubsubd_srv_init ();
diff --git a/lib/pubsubd.h b/lib/pubsubd.h
new file mode 100644
index 0000000..0f20e01
--- /dev/null
+++ b/lib/pubsubd.h
@@ -0,0 +1,68 @@
+#ifndef __PUBSUBD_H__
+#define __PUBSUBD_H__
+
+#include "communication.h"
+#include "process.h"
+
+#include "queue.h"
+
+#define PUBSUB_SERVICE_NAME "pubsub"
+
+struct pubsub_msg {
+    unsigned char *chan;
+    size_t chanlen;
+    unsigned char *data;
+    size_t datalen;
+    unsigned char type; // message type : alert, notification, …
+};
+
+void pubsubd_msg_serialize (const struct pubsub_msg *msg, char **data, size_t *len);
+void pubsubd_msg_unserialize (struct pubsub_msg *msg, const char *data, size_t len);
+void pubsubd_msg_free (struct pubsub_msg *msg);
+
+void pubsubd_msg_send (struct service *, struct pubsub_msg *msg, struct process *p);
+void pubsubd_msg_recv (struct service *, struct pubsub_msg *msg, struct process *p);
+
+void pubsub_msg_send (struct service *, struct pubsub_msg *msg);
+void pubsub_msg_recv (struct service *, struct pubsub_msg *msg);
+
+// CHANNEL
+
+// head of the list
+LIST_HEAD(channels, channel);
+
+// element of the list
+struct channel {
+    unsigned char *chan;
+    size_t chanlen;
+    LIST_ENTRY(channel) entries;
+};
+
+struct channel * pubsubd_channel_copy (struct channel *c);
+struct channel * pubsubd_channel_get (struct channels *chans, struct channel *c);
+
+void pubsubd_channel_free (struct channel *c);
+int pubsubd_channel_eq (const struct channel *c1, const struct channel *c2);
+
+// APPLICATION
+
+// head of the list
+LIST_HEAD(app_list_head, app_list_elm);
+
+// element of the list
+struct app_list_elm {
+    struct process *p;
+    LIST_ENTRY(app_list_elm) entries;
+};
+
+void pubsubd_subscriber_add (const struct app_list_head *
+        , const struct app_list_elm *);
+struct app_list_elm * pubsubd_subscriber_get (const struct app_list_head *
+        , const struct app_list_elm *);
+void pubsubd_subscriber_del (struct app_list_head *al, struct app_list_elm *p);
+
+struct app_list_elm * pubsubd_app_list_elm_copy (struct app_list_elm *ale);
+void pubsubd_app_list_elm_create (struct app_list_elm *ale, struct process *p);
+void pubsubd_app_list_elm_free (struct app_list_elm *todel);
+
+#endif
diff --git a/pingpong/pingpong.c b/pingpong/pingpong.c
index 4b932ba..98a6450 100644
--- a/pingpong/pingpong.c
+++ b/pingpong/pingpong.c
@@ -1,5 +1,7 @@
 #include "../lib/communication.h"
 
+#define PONGD_SERVICE_NAME "pongd"
+
 /*
  * main loop
  *
@@ -8,7 +10,7 @@
  * then closes the pipes
  */
 
-void main_loop (const char *spath)
+void main_loop (const struct service *srv)
 {
     int ret;
     struct process proc;
@@ -17,7 +19,7 @@ void main_loop (const char *spath)
 
     while (cnt--) {
         // -1 : error, 0 = no new process, 1 = new process
-        ret = srv_get_new_process (&proc, spath);
+        ret = srv_get_new_process (&proc, srv);
         if (ret == -1) {
             fprintf (stderr, "error service_get_new_process\n");
             continue;
@@ -64,22 +66,22 @@ void main_loop (const char *spath)
 
 int main(int argc, char * argv[])
 {
-    // gets the service path, such as /tmp/<service>
-    char spath[PATH_MAX];
-    srv_path (spath, "pingpong");
+    struct service srv;
+    srv_init (&srv, PONGD_SERVICE_NAME);
+    printf ("Listening on %s.\n", srv.spath);
 
     // creates the service named pipe, that listens to client applications
     int ret;
-    if ((ret = srv_create (spath))) {
+    if ((ret = srv_create (&srv))) {
         fprintf(stdout, "error service_create %d\n", ret);
         exit (1);
     }
 
     // the service will loop until the end of time, a specific message, a signal
-    main_loop (spath);
+    main_loop (&srv);
 
     // the application will shut down, and remove the service named pipe
-    if ((ret = srv_close (spath))) {
+    if ((ret = srv_close (&srv))) {
         fprintf(stdout, "error service_close %d\n", ret);
         exit (1);
     }
diff --git a/pingpong/pingpong.sh b/pingpong/pingpong.sh
index b622dce..88a38e5 100755
--- a/pingpong/pingpong.sh
+++ b/pingpong/pingpong.sh
@@ -1,7 +1,7 @@
 #!/bin/dash
 
 REP=/tmp/ipc/
-SERVICE="pingpong"
+SERVICE="pongd"
 NB=3
 
 # CLEAN UP !
diff --git a/pubsub/pubsubd.c b/pubsub/pubsubd.c
index 18c32ff..39e333d 100644
--- a/pubsub/pubsubd.c
+++ b/pubsub/pubsubd.c
@@ -1,116 +1,21 @@
-#include "pubsubd.h"
+#include "../lib/pubsubd.h"
 #include <stdlib.h>
 
-const char* service_name = "pubsub";
-
 void
 ohshit(int rvalue, const char* str) {
     fprintf(stderr, "%s\n", str);
     exit(rvalue);
 }
 
-// CHANNELS
-
-void pubsubd_channels_init (struct channels *chans) { LIST_INIT(chans); }
-
-void
-pubsubd_channels_add (struct channels *chans, struct channel *c)
-{
-    if(!chans || !c)
-        return;
-
-    struct channel *n = pubsubd_channel_copy (c);
-    LIST_INSERT_HEAD(al, n, entries);
-}
-
-void
-pubsubd_channels_del (struct app_list *al, struct channel *c)
-{
-    struct channel *todel = pubsubd_channel_get (al, c);
-    if(todel != NULL) {
-        LIST_REMOVE(todel, entries);
-        srv_process_free (mfree, todel);
-        mfree (todel);
-        todel = NULL;
-    }
-}
-
-struct channel * pubsubd_channel_copy (struct channel *c)
-{
-    struct channel *copy;
-    copy = malloc (sizeof(struct channel));
-    memcpy (copy, c, sizeof(struct channel));
-    return copy;
-}
-
-int
-pubsubd_channels_eq (const struct channel *c1, const struct channel *c2)
-{
-    return (strncmp (c1->chan, c2->chan, c1->chanlen) == 0);
-}
-
-// SUBSCRIBER
-
-void pubsubd_subscriber_init (struct app_list *al) { LIST_INIT(al); } 
-
-void
-pubsubd_subscriber_add (struct app_list *al, struct process *p)
-{
-    if(!al || !p)
-        return;
-
-    struct process *n = srv_process_copy (p);
-    LIST_INSERT_HEAD(al, n, entries);
-}
-
-struct process *
-pubsubd_subscriber_get (const struct app_list *al
-        , const struct process *p)
-{
-    struct process *np, *res = NULL;
-    LIST_FOREACH(np, al, entries) {
-        if(srv_process_eq (np, p)) {
-            res = np;
-        }
-    }
-    return res;
-}
-
-void
-pubsubd_subscriber_del (struct app_list *al, struct process *p)
-{
-    struct process *todel = pubsubd_subscriber_get (al, p);
-    if(todel != NULL) {
-        LIST_REMOVE(todel, entries);
-        srv_process_free (mfree, todel);
-        mfree (todel);
-        todel = NULL;
-    }
-}
-
-void pubsubd_msg_send (struct service *s, struct message * m, struct process *p)
-{
-}
-void pubsubd_msg_recv (struct service *s, struct message * m, struct process *p)
-{
-}
-void pubsub_msg_send (struct service *s, struct message * m)
-{
-}
-void pubsub_msg_recv (struct service *s, struct message * m)
-{
-}
-
     int
 main(int argc, char* argv[])
 {
-    // gets the service path, such as /tmp/<service>
-    char s_path[PATH_MAX];
-    service_path (s_path, service_name);
-    printf ("Listening on %s.\n", s_path);
+    struct service srv;
+    srv_init (&srv, PUBSUB_SERVICE_NAME);
+    printf ("Listening on %s.\n", srv->spath);
 
     // creates the service named pipe, that listens to client applications
-    if (service_create (s_path))
+    if (service_create (&srv))
         ohshit(1, "service_create error");
 
     struct channels chans;
@@ -120,7 +25,7 @@ main(int argc, char* argv[])
         struct process proc;
         int proc_count, i;
 
-        service_get_new_process (&proc, s_path);
+        service_get_new_process (&proc, &srv);
 
         printf("> %i proc\n", proc_count);
 
@@ -157,7 +62,7 @@ main(int argc, char* argv[])
  * then closes the pipes
  */
 
-void main_loop (const char *spath)
+void main_loop (const struct service *srv)
 {
     int ret;
     struct process proc;
@@ -166,7 +71,7 @@ void main_loop (const char *spath)
 
     while (cnt--) {
         // -1 : error, 0 = no new process, 1 = new process
-        ret = srv_get_new_process (&proc, spath);
+        ret = srv_get_new_process (&proc, srv);
         if (ret == -1) {
             fprintf (stderr, "error service_get_new_process\n");
             continue;
diff --git a/pubsub/pubsubd.h b/pubsub/pubsubd.h
deleted file mode 100644
index b71f830..0000000
--- a/pubsub/pubsubd.h
+++ /dev/null
@@ -1,46 +0,0 @@
-#ifndef __PUBSUBD_H__
-#define __PUBSUBD_H__
-
-#include "../lib/communication.h"
-#include "../lib/process.h"
-
-#include "../lib/queue.h"
-
-struct message {
-    unsigned char *chan;
-    size_t chanlen;
-    unsigned char *data;
-    size_t datalen;
-    unsigned char type; // message type : alert, notification, …
-};
-
-struct channel {
-    unsigned char *chan;
-    size_t chanlen;
-};
-
-struct channel * pubsubd_channel_copy (struct channel *c);
-
-int pubsubd_channel_eq (const struct channel *c1, const struct channel *c2);
-
-struct channels {
-    struct channel *chan;
-    LIST_ENTRY(channels) entries;
-};
-
-struct app_list {
-    struct process *p;
-    LIST_ENTRY(app_list) entries;
-};
-
-void pubsubd_msg_send (struct service *, struct message *msg, struct process *p);
-void pubsubd_msg_recv (struct service *, struct message *msg, struct process *p);
-
-struct process * pubsubd_subscriber_get (const struct app_list *
-        , const struct process *);
-void pubsubd_subscriber_del (struct app_list *al, struct process *p);
-
-void pubsub_msg_send (struct service *, struct message *msg);
-void pubsub_msg_recv (struct service *, struct message *msg);
-
-#endif