diff --git a/src/WebSockets.h b/src/WebSockets.h
index 91d95eb..00d65b2 100644
--- a/src/WebSockets.h
+++ b/src/WebSockets.h
@@ -259,34 +259,46 @@ typedef struct {
 } WSMessageHeader_t;
 
 typedef struct {
-    uint8_t num;    ///< connection number
 
-    WSclientsStatus_t status;
+    void init (uint8_t  num,
+               uint32_t pingInterval,
+               uint32_t pongTimeout,
+               uint8_t  disconnectTimeoutCount)
+    {
+        this->num = num;
+        this->pingInterval = pingInterval;
+        this->pongTimeout = pongTimeout;
+        this->disconnectTimeoutCount = disconnectTimeoutCount;
+    }
+
+    uint8_t num = 0;    ///< connection number
+
+    WSclientsStatus_t status = WSC_NOT_CONNECTED;
 
-    WEBSOCKETS_NETWORK_CLASS * tcp;
+    WEBSOCKETS_NETWORK_CLASS * tcp = nullptr;
 
-    bool isSocketIO;    ///< client for socket.io server
+    bool isSocketIO = false;    ///< client for socket.io server
 
 #if defined(HAS_SSL)
-    bool isSSL;    ///< run in ssl mode
+    bool isSSL = false;    ///< run in ssl mode
     WEBSOCKETS_NETWORK_SSL_CLASS * ssl;
 #endif
 
-    String cUrl;       ///< http url
-    uint16_t cCode;    ///< http code
+    String cUrl;        ///< http url
+    uint16_t cCode = 0; ///< http code
 
     bool cIsClient = false;    ///< will be used for masking
-    bool cIsUpgrade;           ///< Connection == Upgrade
-    bool cIsWebsocket;         ///< Upgrade == websocket
+    bool cIsUpgrade = false;   ///< Connection == Upgrade
+    bool cIsWebsocket = false; ///< Upgrade == websocket
 
     String cSessionId;     ///< client Set-Cookie (session id)
     String cKey;           ///< client Sec-WebSocket-Key
     String cAccept;        ///< client Sec-WebSocket-Accept
     String cProtocol;      ///< client Sec-WebSocket-Protocol
     String cExtensions;    ///< client Sec-WebSocket-Extensions
-    uint16_t cVersion;     ///< client Sec-WebSocket-Version
+    uint16_t cVersion = 0; ///< client Sec-WebSocket-Version
 
-    uint8_t cWsRXsize;                                ///< State of the RX
+    uint8_t cWsRXsize = 0;                            ///< State of the RX
     uint8_t cWsHeader[WEBSOCKETS_MAX_HEADER_SIZE];    ///< RX WS Message buffer
     WSMessageHeader_t cWsHeaderDecode;
 
@@ -295,15 +307,15 @@ typedef struct {
 
     String extraHeaders;
 
-    bool cHttpHeadersValid;           ///< non-websocket http header validity indicator
+    bool cHttpHeadersValid = false;   ///< non-websocket http header validity indicator
     size_t cMandatoryHeadersCount;    ///< non-websocket mandatory http headers present count
 
-    bool pongReceived;
-    uint32_t pingInterval;             // how often ping will be sent, 0 means "heartbeat is not active"
-    uint32_t lastPing;                 // millis when last pong has been received
-    uint32_t pongTimeout;              // interval in millis after which pong is considered to timeout
-    uint8_t disconnectTimeoutCount;    // after how many subsequent pong timeouts discconnect will happen, 0 means "do not disconnect"
-    uint8_t pongTimeoutCount;          // current pong timeout count
+    bool pongReceived = false;
+    uint32_t pingInterval = 0;          // how often ping will be sent, 0 means "heartbeat is not active"
+    uint32_t lastPing = 0;              // millis when last pong has been received
+    uint32_t pongTimeout = 0;           // interval in millis after which pong is considered to timeout
+    uint8_t disconnectTimeoutCount = 0; // after how many subsequent pong timeouts discconnect will happen, 0 means "do not disconnect"
+    uint8_t pongTimeoutCount = 0;       // current pong timeout count
 
 #if(WEBSOCKETS_NETWORK_TYPE == NETWORK_ESP8266_ASYNC)
     String cHttpLine;    ///< HTTP header lines
diff --git a/src/WebSockets4WebServer.h b/src/WebSockets4WebServer.h
index 01a7f8a..ba2b020 100644
--- a/src/WebSockets4WebServer.h
+++ b/src/WebSockets4WebServer.h
@@ -41,6 +41,8 @@ class WebSockets4WebServer : public WebSocketsServerCore {
         onEvent(event);
 
         return [&, wsRootDir](const String & method, const String & url, WiFiClient * tcpClient, ESP8266WebServer::ContentTypeFunction contentType) {
+            (void)contentType;
+
             if(!(method == "GET" && url.indexOf(wsRootDir) == 0)) {
                 return ESP8266WebServer::CLIENT_REQUEST_CAN_CONTINUE;
             }
diff --git a/src/WebSocketsServer.cpp b/src/WebSocketsServer.cpp
index 20b2373..c8ac2ef 100644
--- a/src/WebSocketsServer.cpp
+++ b/src/WebSocketsServer.cpp
@@ -38,8 +38,6 @@ WebSocketsServerCore::WebSocketsServerCore(const String & origin, const String &
     _httpHeaderValidationFunc = NULL;
     _mandatoryHttpHeaders     = NULL;
     _mandatoryHttpHeaderCount = 0;
-
-    memset(&_clients[0], 0x00, (sizeof(WSclient_t) * WEBSOCKETS_SERVER_CLIENT_MAX));
 }
 
 WebSocketsServer::WebSocketsServer(uint16_t port, const String & origin, const String & protocol)
@@ -73,47 +71,14 @@ WebSocketsServer::~WebSocketsServer() {
  * called to initialize the Websocket server
  */
 void WebSocketsServerCore::begin(void) {
-    WSclient_t * client;
-
-    // init client storage
-    for(uint8_t i = 0; i < WEBSOCKETS_SERVER_CLIENT_MAX; i++) {
-        client = &_clients[i];
-
-        client->num    = i;
-        client->status = WSC_NOT_CONNECTED;
-        client->tcp    = NULL;
-#if(WEBSOCKETS_NETWORK_TYPE == NETWORK_ESP8266) || (WEBSOCKETS_NETWORK_TYPE == NETWORK_ESP32)
-        client->isSSL = false;
-        client->ssl   = NULL;
-#endif
-        client->cUrl  = "";
-        client->cCode = 0;
-
-        client->cIsClient    = false;
-        client->cIsUpgrade   = false;
-        client->cIsWebsocket = false;
 
-        client->cSessionId  = "";
-        client->cKey        = "";
-        client->cAccept     = "";
-        client->cProtocol   = "";
-        client->cExtensions = "";
-        client->cVersion    = 0;
-
-        client->cWsRXsize = 0;
-
-        client->base64Authorization = "";
-        client->plainAuthorization  = "";
-
-        client->extraHeaders = "";
-
-#if(WEBSOCKETS_NETWORK_TYPE == NETWORK_ESP8266_ASYNC)
-        client->cHttpLine = "";
-#endif
-
-        client->pingInterval           = _pingInterval;
-        client->pongTimeout            = _pongTimeout;
-        client->disconnectTimeoutCount = _disconnectTimeoutCount;
+    // adjust clients storage:
+    // _clients[i]'s constructor are already called,
+    // all its members are initialized to their default value,
+    // except the ones explicitly detailed in WSclient_t() constructor.
+    // Then we need to initialize some members to non-trivial values:
+    for (int i = 0; i < WEBSOCKETS_SERVER_CLIENT_MAX; i++) {
+        _clients[i].init(i, _pingInterval, _pongTimeout, _disconnectTimeoutCount);
     }
 
 #ifdef ESP8266
@@ -132,6 +97,12 @@ void WebSocketsServerCore::begin(void) {
 void WebSocketsServerCore::close(void) {
     _runnning = false;
     disconnect();
+
+    // restore _clients[] to their initial state
+    // before next call to ::begin()
+    for (int i = 0; i < WEBSOCKETS_SERVER_CLIENT_MAX; i++) {
+        _clients[i] = WSclient_t();
+    }
 }
 
 /**