diff --git a/src/Network/network_types.h b/src/Network/network_types.h
index 4a9d364..4bffc87 100644
--- a/src/Network/network_types.h
+++ b/src/Network/network_types.h
@@ -7,6 +7,8 @@ extern "C" {
 #include "../base/base.h"
 
 typedef u16 knPort;
+#define knPort_INVALID ((knPort)~0)
+#define knPort_isINVALID(PORT) (PORT == knPort_INVALID)
 
 typedef union knIPV4Address {
     u32 UintBigEndian;
@@ -20,9 +22,10 @@ kt_declare(knIPV4Address);
 ///@return Maybe<knIPV4Address> as Maybe<knIPV4Address>
 Maybe knIPV4Address_fromStr(char* addrStr);
 
-#define knIPV4Address_INVALID  knIPV4Address_fromBytes(255,255,255,255)
 #define knIPV4Address_ANY      knIPV4Address_fromBytes(0,0,0,0)
 #define knIPV4Address_LOOPBACK knIPV4Address_fromBytes(127,0,0,1)
+#define knIPV4Address_INVALID  knIPV4Address_fromBytes(255,255,255,255)
+#define knIPV4Address_isINVALID(ADDR) (ADDR.UintBigEndian == ~0)
 
 char* knIPV4Address_toString(knIPV4Address* address);
 
@@ -34,7 +37,8 @@ STRUCT(knIPV4Endpoint,
 
 #define knIPV4Endpoint_create(ADDR, PORT) ((knIPV4Endpoint){ADDR, PORT})
 
-#define knIPV4Endpoint_INVALID knIPV4Endpoint_create(knIPV4Address_INVALID, ~0)
+#define knIPV4Endpoint_INVALID knIPV4Endpoint_create(knIPV4Address_INVALID, knPort_INVALID)
+#define knIPV4Address_isINVALID(ENDP) (knIPV4Address_isINVALID(ENDP.address) || knPort_isINVALID(ENDP.port))
 
 char* knIPV4Endpoint_toString(knIPV4Endpoint* end);
 
diff --git a/src/Network/sockets/knSocketChanneled.c b/src/Network/sockets/knSocketChanneled.c
index 26106a6..14bc04e 100644
--- a/src/Network/sockets/knSocketChanneled.c
+++ b/src/Network/sockets/knSocketChanneled.c
@@ -9,8 +9,8 @@ kt_define(knSocketChanneled, __knSocketChanneled_close, NULL);
 
 Maybe knSocketChanneled_open(){
     knSocketChanneled* newSocket=malloc(sizeof(knSocketChanneled));
-    newSocket->localEndpoint=knIPV4Endpoint_create(knIPV4Address_fromBytes(0,0,0,0),0);
-    newSocket->remoteEndpoint=newSocket->localEndpoint;
+    newSocket->localEndpoint=knIPV4Endpoint_INVALID;
+    newSocket->remoteEndpoint=knIPV4Endpoint_INVALID;
     newSocket->channels=NULL;
     newSocket->channelsAmount=0;
     return SUCCESS(UniHeapPtr(knSocketChanneled, newSocket));
diff --git a/src/Network/sockets/knSocketUDP.c b/src/Network/sockets/knSocketUDP.c
index b1c429e..27b60a7 100644
--- a/src/Network/sockets/knSocketUDP.c
+++ b/src/Network/sockets/knSocketUDP.c
@@ -6,9 +6,9 @@ kt_define(knSocketUDP, __knSocketUDP_close, NULL);
 
 Maybe knSocketUDP_open(bool allowReuse){
     knSocketUDP* newSocket=malloc(sizeof(knSocketUDP));
-    newSocket->localEndpoint=knIPV4Endpoint_create(knIPV4Address_fromBytes(0,0,0,0),0);
+    newSocket->localEndpoint=knIPV4Endpoint_INVALID;
     newSocket->socketfd=socket(AF_INET, SOCK_DGRAM, 0);
-    if(newSocket->socketfd==-1)
+    if(newSocket->socketfd==-1 || newSocket->socketfd == ~0)
         safethrow("can't create socket", free(newSocket));
     
     // set value of REUSEADDR socket option