diff --git a/mongoose.h b/mongoose.h
index 19608ca4..52a032a3 100644
--- a/mongoose.h
+++ b/mongoose.h
@@ -1061,6 +1061,10 @@ struct timeval {
 #define MG_SET_MAC_ADDRESS(mac)
 #endif
 
+#ifndef MG_TCPIP_DHCPNAME_SIZE
+#define MG_TCPIP_DHCPNAME_SIZE 18  // struct mg_tcpip_if :: dhcp_name size
+#endif
+
 #ifndef MG_SET_WIFI_CONFIG
 #define MG_SET_WIFI_CONFIG(data)
 #endif
@@ -3082,19 +3086,20 @@ typedef void (*mg_tcpip_event_handler_t)(struct mg_tcpip_if *ifp, int ev,
                                          void *ev_data);
 
 enum {
-  MG_TCPIP_EV_ST_CHG,           // state change                   uint8_t * (&ifp->state)
-  MG_TCPIP_EV_DHCP_DNS,         // DHCP DNS assignment            uint32_t *ipaddr
-  MG_TCPIP_EV_DHCP_SNTP,        // DHCP SNTP assignment           uint32_t *ipaddr
-  MG_TCPIP_EV_ARP,              // Got ARP packet                 struct mg_str *
-  MG_TCPIP_EV_TIMER_1S,         // 1 second timer                 NULL
-  MG_TCPIP_EV_WIFI_SCAN_RESULT, // Wi-Fi scan results             struct mg_wifi_scan_bss_data *
-  MG_TCPIP_EV_WIFI_SCAN_END,    // Wi-Fi scan has finished        NULL
-  MG_TCPIP_EV_WIFI_CONNECT_ERR, // Wi-Fi connect has failed       driver and chip specific
-  MG_TCPIP_EV_DRIVER,           // Driver event                   driver specific
-  MG_TCPIP_EV_USER              // Starting ID for user events
+  MG_TCPIP_EV_ST_CHG,  // state change                   uint8_t * (&ifp->state)
+  MG_TCPIP_EV_DHCP_DNS,   // DHCP DNS assignment            uint32_t *ipaddr
+  MG_TCPIP_EV_DHCP_SNTP,  // DHCP SNTP assignment           uint32_t *ipaddr
+  MG_TCPIP_EV_ARP,        // Got ARP packet                 struct mg_str *
+  MG_TCPIP_EV_TIMER_1S,   // 1 second timer                 NULL
+  MG_TCPIP_EV_WIFI_SCAN_RESULT,  // Wi-Fi scan results             struct
+                                 // mg_wifi_scan_bss_data *
+  MG_TCPIP_EV_WIFI_SCAN_END,     // Wi-Fi scan has finished        NULL
+  MG_TCPIP_EV_WIFI_CONNECT_ERR,  // Wi-Fi connect has failed       driver and
+                                 // chip specific
+  MG_TCPIP_EV_DRIVER,  // Driver event                   driver specific
+  MG_TCPIP_EV_USER     // Starting ID for user events
 };
 
-
 // Network interface
 struct mg_tcpip_if {
   uint8_t mac[6];                  // MAC address. Must be set to a valid MAC
@@ -3114,8 +3119,8 @@ struct mg_tcpip_if {
   mg_tcpip_event_handler_t fn;     // User-specified event handler function
   struct mg_mgr *mgr;              // Mongoose event manager
   struct mg_queue recv_queue;      // Receive queue
-  char dhcp_name[12];              // Name reported to DHCP, "mip" if unset
-  uint16_t mtu;                    // Interface MTU
+  char dhcp_name[MG_TCPIP_DHCPNAME_SIZE];  // Name for DHCP, "mip" if unset
+  uint16_t mtu;                            // Interface MTU
 #define MG_TCPIP_MTU_DEFAULT 1500
 
   // Internal state, user can use it but should not change it
@@ -3168,7 +3173,6 @@ struct mg_tcpip_spi {
   uint8_t (*txn)(void *, uint8_t);  // SPI transaction: write 1 byte, read reply
 };
 
-
 #endif
 
 
diff --git a/src/config.h b/src/config.h
index 23be2982..0a8dea4d 100644
--- a/src/config.h
+++ b/src/config.h
@@ -179,6 +179,10 @@
 #define MG_SET_MAC_ADDRESS(mac)
 #endif
 
+#ifndef MG_TCPIP_DHCPNAME_SIZE
+#define MG_TCPIP_DHCPNAME_SIZE 18  // struct mg_tcpip_if :: dhcp_name size
+#endif
+
 #ifndef MG_SET_WIFI_CONFIG
 #define MG_SET_WIFI_CONFIG(data)
 #endif
diff --git a/src/net_builtin.h b/src/net_builtin.h
index 524dc9c6..b3c1494c 100644
--- a/src/net_builtin.h
+++ b/src/net_builtin.h
@@ -20,19 +20,20 @@ typedef void (*mg_tcpip_event_handler_t)(struct mg_tcpip_if *ifp, int ev,
                                          void *ev_data);
 
 enum {
-  MG_TCPIP_EV_ST_CHG,           // state change                   uint8_t * (&ifp->state)
-  MG_TCPIP_EV_DHCP_DNS,         // DHCP DNS assignment            uint32_t *ipaddr
-  MG_TCPIP_EV_DHCP_SNTP,        // DHCP SNTP assignment           uint32_t *ipaddr
-  MG_TCPIP_EV_ARP,              // Got ARP packet                 struct mg_str *
-  MG_TCPIP_EV_TIMER_1S,         // 1 second timer                 NULL
-  MG_TCPIP_EV_WIFI_SCAN_RESULT, // Wi-Fi scan results             struct mg_wifi_scan_bss_data *
-  MG_TCPIP_EV_WIFI_SCAN_END,    // Wi-Fi scan has finished        NULL
-  MG_TCPIP_EV_WIFI_CONNECT_ERR, // Wi-Fi connect has failed       driver and chip specific
-  MG_TCPIP_EV_DRIVER,           // Driver event                   driver specific
-  MG_TCPIP_EV_USER              // Starting ID for user events
+  MG_TCPIP_EV_ST_CHG,  // state change                   uint8_t * (&ifp->state)
+  MG_TCPIP_EV_DHCP_DNS,   // DHCP DNS assignment            uint32_t *ipaddr
+  MG_TCPIP_EV_DHCP_SNTP,  // DHCP SNTP assignment           uint32_t *ipaddr
+  MG_TCPIP_EV_ARP,        // Got ARP packet                 struct mg_str *
+  MG_TCPIP_EV_TIMER_1S,   // 1 second timer                 NULL
+  MG_TCPIP_EV_WIFI_SCAN_RESULT,  // Wi-Fi scan results             struct
+                                 // mg_wifi_scan_bss_data *
+  MG_TCPIP_EV_WIFI_SCAN_END,     // Wi-Fi scan has finished        NULL
+  MG_TCPIP_EV_WIFI_CONNECT_ERR,  // Wi-Fi connect has failed       driver and
+                                 // chip specific
+  MG_TCPIP_EV_DRIVER,  // Driver event                   driver specific
+  MG_TCPIP_EV_USER     // Starting ID for user events
 };
 
-
 // Network interface
 struct mg_tcpip_if {
   uint8_t mac[6];                  // MAC address. Must be set to a valid MAC
@@ -52,8 +53,8 @@ struct mg_tcpip_if {
   mg_tcpip_event_handler_t fn;     // User-specified event handler function
   struct mg_mgr *mgr;              // Mongoose event manager
   struct mg_queue recv_queue;      // Receive queue
-  char dhcp_name[12];              // Name reported to DHCP, "mip" if unset
-  uint16_t mtu;                    // Interface MTU
+  char dhcp_name[MG_TCPIP_DHCPNAME_SIZE];  // Name for DHCP, "mip" if unset
+  uint16_t mtu;                            // Interface MTU
 #define MG_TCPIP_MTU_DEFAULT 1500
 
   // Internal state, user can use it but should not change it
@@ -106,5 +107,4 @@ struct mg_tcpip_spi {
   uint8_t (*txn)(void *, uint8_t);  // SPI transaction: write 1 byte, read reply
 };
 
-
 #endif