diff --git a/src/config.c b/src/config.c
index cedc617..17567c0 100644
--- a/src/config.c
+++ b/src/config.c
@@ -35,7 +35,8 @@ main_config_t get_main_config(void)
 	HKEY reg      = reg_open_main(false);
 	DWORD version = reg_get_dword(reg, "config_version", 1);
 	
-	config.single_iface   = reg_get_dword(reg, "single_iface", true);
+	config.iface_mode     = reg_get_dword(reg, "iface_mode", IFACE_MODE_ALL);
+	
 	config.single_netnum  = reg_get_addr32(reg, "single_netnum", addr32_in((unsigned char[]){0x00, 0x00, 0x00, 0x01}));
 	config.single_nodenum = reg_get_addr48(reg, "single_nodenum", 0);
 	
@@ -90,7 +91,7 @@ bool set_main_config(const main_config_t *config)
 {
 	HKEY reg = reg_open_main(true);
 	
-	bool ok = reg_set_dword(reg, "single_iface", config->single_iface)
+	bool ok = reg_set_dword(reg, "iface_mode", config->iface_mode)
 		&& reg_set_addr32(reg, "single_netnum", config->single_netnum)
 		&& reg_set_addr48(reg, "single_nodenum", config->single_nodenum)
 		
diff --git a/src/config.h b/src/config.h
index 7a53b54..3eb8a19 100644
--- a/src/config.h
+++ b/src/config.h
@@ -21,6 +21,26 @@
 #define DEFAULT_PORT 54792
 #define DEFAULT_ROUTER_PORT 54793
 
+/* IFACE_MODE_ALL
+ * 
+ * Packets are sent/received on all interfaces and no source address filtering
+ * is performed. A single IPX interface is presented.
+ * 
+ * IFACE_MODE_SINGLE
+ * 
+ * Packets are sent/received on user-chosen interfaces. A single IPX interface
+ * is presented.
+ * 
+ * IFACE_MODE_MULTI
+ * 
+ * An IPX interface is presented for each (enabled) real interface and packets
+ * are sent or received on the single underlying interface of the IPX one.
+*/
+
+#define IFACE_MODE_ALL    1
+#define IFACE_MODE_SINGLE 2
+#define IFACE_MODE_MULTI  3
+
 #include "common.h"
 
 #ifdef __cplusplus
@@ -37,7 +57,8 @@ typedef struct main_config {
 	
 	enum ipx_log_level log_level;
 	
-	bool single_iface;
+	int iface_mode;
+	
 	addr32_t single_netnum;
 	addr48_t single_nodenum;
 } main_config_t;