diff --git a/coap-simple.cpp b/coap-simple.cpp
index cfd7f5d..8f7189e 100644
--- a/coap-simple.cpp
+++ b/coap-simple.cpp
@@ -124,6 +124,10 @@ uint16_t Coap::send(IPAddress ip, int port, const char *url, COAP_TYPE type, COA
 }
 
 uint16_t Coap::send(IPAddress ip, int port, const char *url, COAP_TYPE type, COAP_METHOD method, const uint8_t *token, uint8_t tokenlen, const uint8_t *payload, size_t payloadlen, COAP_CONTENT_TYPE content_type) {
+    return this->send(ip, port, url, type, method, token, tokenlen, payload, payloadlen, content_type, rand());
+}
+
+uint16_t Coap::send(IPAddress ip, int port, const char *url, COAP_TYPE type, COAP_METHOD method, const uint8_t *token, uint8_t tokenlen, const uint8_t *payload, size_t payloadlen, COAP_CONTENT_TYPE content_type, uint16_t messageid) {
 
     // make packet
     CoapPacket packet;
@@ -135,7 +139,7 @@ uint16_t Coap::send(IPAddress ip, int port, const char *url, COAP_TYPE type, COA
     packet.payload = payload;
     packet.payloadlen = payloadlen;
     packet.optionnum = 0;
-    packet.messageid = rand();
+    packet.messageid = messageid;
 
     // use URI_HOST UIR_PATH
     char ipaddress[16] = "";
diff --git a/coap-simple.h b/coap-simple.h
index a4512f0..0b50239 100644
--- a/coap-simple.h
+++ b/coap-simple.h
@@ -201,6 +201,7 @@ class Coap {
         uint16_t put(IPAddress ip, int port, const char *url, const char *payload, size_t payloadlen);
         uint16_t send(IPAddress ip, int port, const char *url, COAP_TYPE type, COAP_METHOD method, const uint8_t *token, uint8_t tokenlen, const uint8_t *payload, size_t payloadlen);
         uint16_t send(IPAddress ip, int port, const char *url, COAP_TYPE type, COAP_METHOD method, const uint8_t *token, uint8_t tokenlen, const uint8_t *payload, size_t payloadlen, COAP_CONTENT_TYPE content_type);
+        uint16_t send(IPAddress ip, int port, const char *url, COAP_TYPE type, COAP_METHOD method, const uint8_t *token, uint8_t tokenlen, const uint8_t *payload, size_t payloadlen, COAP_CONTENT_TYPE content_type, uint16_t messageid);
 
         bool loop();
 };