diff --git a/sys/netinet/tcp.h b/sys/netinet/tcp.h
index 0143bcabf384..782e1ef4f78b 100644
--- a/sys/netinet/tcp.h
+++ b/sys/netinet/tcp.h
@@ -111,15 +111,14 @@ struct tcphdr {
  */
 #define	TCP_MSS	512
 /*
- * TCP_MINMSS is defined to be 256 which is fine for the smallest
- * link MTU (296 bytes, SLIP interface) in the Internet.
+ * TCP_MINMSS is defined to be 216 which is fine for the smallest
+ * link MTU (256 bytes, AX.25 packet radio) in the Internet.
  * However it is very unlikely to come across such low MTU interfaces
  * these days (anno dato 2003).
- * Probably it can be set to 512 without ill effects. But we play safe.
  * See tcp_subr.c tcp_minmss SYSCTL declaration for more comments.
  * Setting this to "0" disables the minmss check.
  */
-#define	TCP_MINMSS 256
+#define	TCP_MINMSS 216
 /*
  * TCP_MINMSSOVERLOAD is defined to be 1000 which should cover any type
  * of interactive TCP session.