diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index c7110e8..d5ec6a7 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -2205,7 +2205,7 @@
         p = (char *) opt.sig_algs;
         i = 0;
 
-        /* Leave room for a final NULL in signature algorithm list */
+        /* Leave room for a final MBEDTLS_TLS13_SIG_NONE in signature algorithm list(sig_alg_list) */
         while( i < SIG_ALG_LIST_SIZE - 1 && *p != '\0' )
         {
             q = p;