diff --git a/sys/intermud.h b/sys/intermud.h
new file mode 100644
index 0000000..12ee567
--- /dev/null
+++ b/sys/intermud.h
@@ -0,0 +1,52 @@
+#define INETD "/secure/inetd/inetd"
+
+// ****** Defines for field names ****************
+#define RECIPIENT       "RCPNT"
+#define REQUEST         "REQ"
+#define SENDER          "SND"
+/* The DATA field should be used to store the main body of any packet. */
+#define DATA            "DATA"
+/* These headers are reserved for system use only. */
+#define HOST            "HST"
+#define ID              "ID"
+#define NAME            "NAME"
+#define PACKET          "PKT"
+#define UDP_PORT        "UDP"
+#define SYSTEM          "SYS"
+#define VERSION         "V"
+#define FLAGS           "F"
+#define SIGNATURE       "S"
+
+/* Reserved headers for diagnostics. */
+#define PACKET_LOSS     "PKT_LOSS"
+#define RESPONSE_TIME   "TIME"
+
+/* --- Standard REQUESTs --- */
+#define PING            "ping"
+#define QUERY           "query"
+#define REPLY           "reply"
+#define HELO            "helo"
+
+// packet properties
+#define MAX_UDP_LENGTH 65536
+// packet flags
+#define FL_VALID_SIGNATURE 0x1
+
+/* --- Index macros for host arrays in old-style host lists --- */
+#define HOSTLIST_NAME       0
+#define HOSTLIST_IP         1
+#define HOSTLIST_UDP_PORT   2
+#define HOSTLIST_LOCAL_COMMANDS  3
+#define HOSTLIST_COMMANDS   4
+#define HOSTLIST_STATUS     5
+#define HOSTFILE_DEL        ":"
+#define HOSTFILE_DEL2        ","
+
+/* Mud / Admin email address. */
+#define EMAIL        "mud@mg.mud.de"
+
+// Public commands which are usually accessible.
+#define DEFAULT_COMMANDS \
+({ PING, QUERY, REPLY, "channel", "finger", "tell", "who", "mail",\
+    "www", "htmlwho", "locate" })
+