diff --git a/communication_techniques/Makefile b/communication_techniques/Makefile
index ee50b7c..97fa3fe 100644
--- a/communication_techniques/Makefile
+++ b/communication_techniques/Makefile
@@ -13,7 +13,7 @@ PAPIHIGHLEVELINCDIR=include
 # I know -finline-functions and -finline-functions-called-once are enabled by
 # -O3 but I did this in case gcc behaviour change one day
 CFLAGS=-g -O3 -finline-functions -finline-functions-called-once -Wall -Werror
-LDFLAGS=-L$(LIBDIR) -L$(LOCALDIR)/$(PAPIHIGHLEVELLIBDIR) -Wl,-rpath-link,$(HOME)/local/lib -lpthread -lpapihighlevel
+LDFLAGS=-L$(LIBDIR) -L$(LOCALDIR)/$(PAPIHIGHLEVELLIBDIR) -Wl,-rpath-link,$(HOME)/local/lib -lpthread -lpapihighlevel -ldl
 
 # Executables
 CC=gcc
diff --git a/communication_techniques/src/main.c b/communication_techniques/src/main.c
index f11ee60..4e24fd2 100644
--- a/communication_techniques/src/main.c
+++ b/communication_techniques/src/main.c
@@ -9,6 +9,7 @@
 #include <limits.h>
 #include <sys/stat.h>
 #include <string.h>
+#include <dlfcn.h>
 
 /* Non standards includes */
 #include <papihighlevel.h>
@@ -22,7 +23,9 @@
 
 static long nb_bufs_sent = 0;
 long nb_prod = 0;
-static char *calculation_lib = NULL;
+static void (*init_calc)(void) = NULL;
+static void *(*do_calc)(void) = NULL;
+static void (*end_calc)(void) = NULL;
 static int shared = 0;
 pthread_cond_t cond_cons_has_finished = PTHREAD_COND_INITIALIZER;
 pthread_mutex_t mutex_cons_has_finished = PTHREAD_MUTEX_INITIALIZER;
@@ -39,13 +42,24 @@ void usage(char *argv[])
 		"Facultative options :\n"
 		"-h\t\t\tPrint this help\n"
 		"-s\t\t\tShare the same L2 cache or not\n"
-		"-c calculation_lib\tLibrary to use for calculation\n"
+		"-c calculation_libname\tLibrary to use for calculation\n"
 		"\t\t\tThis library must implement functions in calc.h\n";
 	printf("Usage : %s %s\n", argv[0], format);
 	printf("Options :\n");
 	printf("%s\n", options);
 }
 
+void do_nothing(void)
+{
+}
+
+void *do_nocalc(void)
+{
+	static int an_int;
+
+	return &an_int;
+}
+
 int analyse_options(int argc, char *argv[])
 {
 	int opt;
@@ -56,12 +70,27 @@ int analyse_options(int argc, char *argv[])
 		switch (opt)
 		{
 			case 'c' :
-				calculation_lib = optarg;
 				{
 					struct stat file_stat;
-					if (stat(calculation_lib, &file_stat))
+					void *dl_descriptor;
+
+					if (stat(optarg, &file_stat))
 					{
-						printf("%s: %s\n", optarg, strerror(errno));
+						fprintf(stderr, "%s: %s\n", optarg, strerror(errno));
+						return -1;
+					}
+					dl_descriptor = dlopen(optarg, RTLD_LAZY | RTLD_LOCAL);
+					if (dl_descriptor == NULL)
+					{
+						fprintf(stderr, "dlopen error: %s\n", dlerror());
+						return -1;
+					}
+					init_calc = dlsym(dl_descriptor, "init_calc");
+					do_calc = dlsym(dl_descriptor, "do_calc");
+					end_calc = dlsym(dl_descriptor, "end_calc");
+					if ((init_calc == NULL) || (do_calc == NULL) || (end_calc == NULL))
+					{
+						fprintf(stderr, "A symbol cannot be loaded: %s\n", dlerror());
 						return -1;
 					}
 				}
@@ -131,13 +160,18 @@ int analyse_options(int argc, char *argv[])
 		fprintf(stderr, "Too many producers to fit with the consumer in processors which share a same cache\n");
 		return -1;
 	}
+	if (do_calc == NULL)
+	{
+		init_calc = do_nothing;
+		do_calc = do_nocalc;
+		end_calc = do_nothing;
+	}
 	return 0;
 }
 
 void *producer(void *unused)
 {
 	int i, j;
-	void *k;
 
 	init_producer_thread();
 	if (shared)
@@ -168,20 +202,17 @@ void *producer(void *unused)
 			return NULL;
 		}
 	}
-	k = (void *) 0x6384923;
+	init_calc();
 	if (initialize_papi() != -1)
 	{
 		for(i = 0; i < nb_bufs_sent; i++) {
 			//printf("[%p] Send %d new CACHE_LINE\n", (void *) pthread_self(), BUF_SIZE / CACHE_LINE_SIZE);
 			for(j = 0; j < (BUF_SIZE / sizeof(uintptr_t)); j++)
-			{
-				send(&k);
-				if (unlikely(calculation_lib != NULL))
-					usleep(1000);
-			}
+				send(do_calc());
 		}
 		print_results(BUF_SIZE / sizeof(uintptr_t), nb_bufs_sent);
 	}
+	end_calc();
 	printf("[%p] Producer finished !\n", (void*) pthread_self());
 	/* 
 	 * When a producer end its thread-local storage vanished. Thus,