diff --git a/controller/EmbeddedNetworkController.cpp b/controller/EmbeddedNetworkController.cpp
index 2ccc16b8c..8826dde57 100644
--- a/controller/EmbeddedNetworkController.cpp
+++ b/controller/EmbeddedNetworkController.cpp
@@ -1235,6 +1235,7 @@ void EmbeddedNetworkController::_request(
 	const Identity &identity,
 	const Dictionary<ZT_NETWORKCONFIG_METADATA_DICT_CAPACITY> &metaData)
 {
+    std::lock_guard<std::mutex> l(_request_l);
 	char nwids[24];
 	DB::NetworkSummaryInfo ns;
 	json network,member;
@@ -1736,7 +1737,7 @@ void EmbeddedNetworkController::_request(
 
 					if ((ipRangeEnd < ipRangeStart)||(ipRangeStart == 0))
 						continue;
-					uint32_t ipRangeLen = ipRangeEnd - ipRangeStart;
+					uint32_t ipRangeLen = ipRangeEnd - ipRangeStart + 1;
 
 					// Start with the LSB of the member's address
 					uint32_t ipTrialCounter = (uint32_t)(identity.address().toInt() & 0xffffffff);
diff --git a/controller/EmbeddedNetworkController.hpp b/controller/EmbeddedNetworkController.hpp
index bc95acb58..930eef511 100644
--- a/controller/EmbeddedNetworkController.hpp
+++ b/controller/EmbeddedNetworkController.hpp
@@ -160,6 +160,8 @@ private:
 
 	RedisConfig *_rc;
 	std::string _ssoRedirectURL;
+
+	std::mutex _request_l;
 };
 
 } // namespace ZeroTier