diff --git a/attic/MTUDPSocket.hpp b/attic/MTUDPSocket.hpp
new file mode 100644
index 000000000..365bbf9cd
--- /dev/null
+++ b/attic/MTUDPSocket.hpp
@@ -0,0 +1,162 @@
+/*
+ * ZeroTier One - Network Virtualization Everywhere
+ * Copyright (C) 2011-2019  ZeroTier, Inc.  https://www.zerotier.com/
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * --
+ *
+ * You can be released from the requirements of the license by purchasing
+ * a commercial license. Buying such a license is mandatory as soon as you
+ * develop commercial closed-source software that incorporates or links
+ * directly against ZeroTier software without disclosing the source code
+ * of your own application.
+ */
+
+#ifndef ZT_MTUDPSOCKET_HPP
+#define ZT_MTUDPSOCKET_HPP
+
+#ifndef __WINDOWS__
+
+#include "../node/Constants.hpp"
+#include "../include/ZeroTierOne.h"
+#include "../osdep/OSUtils.hpp"
+#include "../osdep/Thread.hpp"
+
+#include <vector>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+namespace ZeroTier {
+
+/**
+ * MTUDPSocket is a multithreaded UDP socket using multiple binds and SO_REUSEPORT
+ * 
+ * On Mac and Linux this is the most efficient way to implement a multithreaded UDP
+ * I/O path. On Windows it's probably not necessary to optimize this much. If it ever
+ * is, we will have to implement a version of this the Windows way.
+ */
+class MTUDPSocket
+{
+public:
+	inline MTUDPSocket(ZT_Node *n,volatile int64_t *dptr,const struct sockaddr *bindAddr)
+	{
+		const int ncores = std::max(1,(int)sysconf(_SC_NPROCESSORS_CONF));
+		for(int t=0;t<ncores;t++) {
+			int s = socket(bindAddr->sa_family,SOCK_DGRAM,0);
+			if (s < 0) {
+				for(auto i=_sockets.begin();i!=_sockets.end();++i)
+					close(*i);
+				throw std::runtime_error("unable to allocate socket");
+			}
+
+			int f = 131072;
+			setsockopt(s,SOL_SOCKET,SO_RCVBUF,(const char *)&f,sizeof(f));
+			f = 131072;
+			setsockopt(s,SOL_SOCKET,SO_SNDBUF,(const char *)&f,sizeof(f));
+
+			if (bindAddr->sa_family == AF_INET6) {
+				f = 1; setsockopt(s,IPPROTO_IPV6,IPV6_V6ONLY,(void *)&f,sizeof(f));
+#ifdef IPV6_MTU_DISCOVER
+				f = 0; setsockopt(s,IPPROTO_IPV6,IPV6_MTU_DISCOVER,&f,sizeof(f));
+#endif
+#ifdef IPV6_DONTFRAG
+				f = 0; setsockopt(s,IPPROTO_IPV6,IPV6_DONTFRAG,&f,sizeof(f));
+#endif
+			}
+			f = 1; setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(void *)&f,sizeof(f));
+			f = 1; setsockopt(s,SOL_SOCKET,SO_REUSEPORT,(void *)&f,sizeof(f));
+			f = 1; setsockopt(s,SOL_SOCKET,SO_BROADCAST,(void *)&f,sizeof(f));
+#ifdef IP_DONTFRAG
+			f = 0; setsockopt(s,IPPROTO_IP,IP_DONTFRAG,&f,sizeof(f));
+#endif
+#ifdef IP_MTU_DISCOVER
+			f = 0; setsockopt(s,IPPROTO_IP,IP_MTU_DISCOVER,&f,sizeof(f));
+#endif
+#ifdef SO_NO_CHECK
+			if (bindAddr->sa_family == AF_INET) {
+				f = 1; setsockopt(s,SOL_SOCKET,SO_NO_CHECK,(void *)&f,sizeof(f));
+			}
+#endif
+
+			if (bind(s,bindAddr,(bindAddr->sa_family == AF_INET) ? sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6))) {
+				for(auto i=_sockets.begin();i!=_sockets.end();++i)
+					close(*i);
+				throw std::runtime_error("unable to bind to address");
+			}
+
+			_sockets.push_back(s);
+		}
+
+		for(auto s=_sockets.begin();s!=_sockets.end();++s) {
+			try {
+				new MTUDPThread(n,dptr,*s);
+			} catch ( ... ) {
+				for(auto i=_sockets.begin();i!=_sockets.end();++i)
+					close(*i);
+				throw;
+			}
+		}
+	}
+
+	inline ~MTUDPSocket()
+	{
+		for(auto i=_sockets.begin();i!=_sockets.end();++i)
+			close(*i);
+	}
+
+private:
+	class MTUDPThread
+	{
+	public:
+		inline MTUDPThread(ZT_Node *n,volatile int64_t *dptr,int s) :
+			node(n),
+			deadlinePtr(dptr),
+			sock(s),
+			thread(Thread::start(this))
+		{
+		}
+
+		inline void threadMain()
+		{
+			struct sockaddr_storage from;
+			for(;;) {
+				socklen_t fromLen = sizeof(from);
+				const int nr = recvfrom(this->sock,this->buf,sizeof(this->buf),0,(struct sockaddr *)&from,&fromLen);
+				if (nr > 0) {
+					ZT_Node_processWirePacket(this->node,nullptr,OSUtils::now(),(int64_t)this->sock,&from,this->buf,(unsigned int)nr,this->deadlinePtr);
+				} else {
+					close(this->sock);
+					break;
+				}
+			}
+			delete this; // closing the socket causes this to exit and delete itself
+		}
+
+		ZT_Node *const node;
+		volatile int64_t *const deadlinePtr;
+		const int sock;
+		Thread thread;
+		char buf[10000];
+	};
+
+	std::vector<int> _sockets;
+};
+
+} // namespace ZeroTier
+
+#endif // !__WINDOWS__
+
+#endif
diff --git a/osdep/Phy.hpp b/osdep/Phy.hpp
index 333e5c244..58843dc86 100644
--- a/osdep/Phy.hpp
+++ b/osdep/Phy.hpp
@@ -61,6 +61,7 @@
 #include <sys/un.h>
 #include <arpa/inet.h>
 #include <netinet/in.h>
+#include <netinet/ip6.h>
 #include <netinet/tcp.h>
 
 #if defined(__linux__) || defined(linux) || defined(__LINUX__) || defined(__linux)
diff --git a/root.cpp b/root.cpp
new file mode 100644
index 000000000..aa05da7b2
--- /dev/null
+++ b/root.cpp
@@ -0,0 +1,158 @@
+/*
+ * ZeroTier One - Network Virtualization Everywhere
+ * Copyright (C) 2011-2019  ZeroTier, Inc.  https://www.zerotier.com/
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * --
+ *
+ * You can be released from the requirements of the license by purchasing
+ * a commercial license. Buying such a license is mandatory as soon as you
+ * develop commercial closed-source software that incorporates or links
+ * directly against ZeroTier software without disclosing the source code
+ * of your own application.
+ */
+
+#include "node/Constants.hpp"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/select.h>
+#include <sys/time.h>
+#include <sys/un.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/tcp.h>
+
+#include <string>
+#include <thread>
+#include <map>
+#include <vector>
+#include <iostream>
+
+#include "include/ZeroTierOne.h"
+
+static int bindSocket(struct sockaddr *bindAddr)
+{
+	int s = socket(bindAddr->sa_family,SOCK_DGRAM,0);
+	if (s < 0) {
+		close(s);
+		return -1;
+	}
+
+	int f = 131072;
+	setsockopt(s,SOL_SOCKET,SO_RCVBUF,(const char *)&f,sizeof(f));
+	f = 131072;
+	setsockopt(s,SOL_SOCKET,SO_SNDBUF,(const char *)&f,sizeof(f));
+
+	if (bindAddr->sa_family == AF_INET6) {
+		f = 1; setsockopt(s,IPPROTO_IPV6,IPV6_V6ONLY,(void *)&f,sizeof(f));
+#ifdef IPV6_MTU_DISCOVER
+		f = 0; setsockopt(s,IPPROTO_IPV6,IPV6_MTU_DISCOVER,&f,sizeof(f));
+#endif
+#ifdef IPV6_DONTFRAG
+		f = 0; setsockopt(s,IPPROTO_IPV6,IPV6_DONTFRAG,&f,sizeof(f));
+#endif
+	}
+	f = 1; setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(void *)&f,sizeof(f));
+	f = 1; setsockopt(s,SOL_SOCKET,SO_REUSEPORT,(void *)&f,sizeof(f));
+	f = 1; setsockopt(s,SOL_SOCKET,SO_BROADCAST,(void *)&f,sizeof(f));
+#ifdef IP_DONTFRAG
+	f = 0; setsockopt(s,IPPROTO_IP,IP_DONTFRAG,&f,sizeof(f));
+#endif
+#ifdef IP_MTU_DISCOVER
+	f = IP_PMTUDISC_DONT; setsockopt(s,IPPROTO_IP,IP_MTU_DISCOVER,&f,sizeof(f));
+#endif
+#ifdef SO_NO_CHECK
+	if (bindAddr->sa_family == AF_INET) {
+		f = 1; setsockopt(s,SOL_SOCKET,SO_NO_CHECK,(void *)&f,sizeof(f));
+	}
+#endif
+
+	if (bind(s,bindAddr,(bindAddr->sa_family == AF_INET) ? sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6))) {
+		close(s);
+		return -1;
+	}
+
+	return s;
+}
+
+int main(int argc,char **argv)
+{
+	unsigned int ncores = std::thread::hardware_concurrency();
+	if (ncores == 0) ncores = 1;
+
+	std::vector<int> sockets;
+	std::vector<std::thread> threads;
+	for(unsigned int tn=0;tn<ncores;++tn) {
+		struct sockaddr_in6 in6;
+		memset(&in6,0,sizeof(in6));
+		in6.sin6_family = AF_INET6;
+		in6.sin6_port = htons(ZT_DEFAULT_PORT);
+		const int s6 = bindSocket((struct sockaddr *)&in6);
+		if (s6 < 0) {
+			std::cout << "ERROR: unable to bind to port " << ZT_DEFAULT_PORT << ZT_EOL_S;
+			exit(1);
+		}
+
+		struct sockaddr_in in4;
+		memset(&in4,0,sizeof(in4));
+		in4.sin_family = AF_INET;
+		in4.sin_port = htons(ZT_DEFAULT_PORT);
+		const int s4 = bindSocket((struct sockaddr *)&in4);
+		if (s4 < 0) {
+			std::cout << "ERROR: unable to bind to port " << ZT_DEFAULT_PORT << ZT_EOL_S;
+			exit(1);
+		}
+
+		sockets.push_back(s6);
+		sockets.push_back(s4);
+
+		threads.push_back(std::thread([s6]() {
+			struct sockaddr_in6 in6;
+			char buf[10000];
+			memset(&in6,0,sizeof(in6));
+			for(;;) {
+				socklen_t sl = sizeof(in6);
+				const int pl = (int)recvfrom(s6,buf,sizeof(buf),0,(struct sockaddr *)&in6,&sl);
+				if (pl > 0) {
+				} else break;
+			}
+		}));
+
+		threads.push_back(std::thread([s4]() {
+			struct sockaddr_in in4;
+			char buf[10000];
+			memset(&in4,0,sizeof(in4));
+			for(;;) {
+				socklen_t sl = sizeof(in4);
+				const int pl = (int)recvfrom(s4,buf,sizeof(buf),0,(struct sockaddr *)&in4,&sl);
+				if (pl > 0) {
+				} else break;
+			}
+		}));
+	}
+
+	return 0;
+}