Tons of code cleanup, refactor Network to use EthernetTapFactory, probably also fix GitHub issue #90

27 files changed, 171 insertions, 1549 deletions

diff --git a/ext/lz4/lz4hc.c b/ext/lz4/lz4hc.c
deleted file mode 100644
index 60867490..00000000
--- a/ext/lz4/lz4hc.c
+++ /dev/null
@@ -1,892 +0,0 @@
-/*
-   LZ4 HC - High Compression Mode of LZ4
-   Copyright (C) 2011-2014, Yann Collet.
-   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
-
-   Redistribution and use in source and binary forms, with or without
-   modification, are permitted provided that the following conditions are
-   met:
-
-       * Redistributions of source code must retain the above copyright
-   notice, this list of conditions and the following disclaimer.
-       * Redistributions in binary form must reproduce the above
-   copyright notice, this list of conditions and the following disclaimer
-   in the documentation and/or other materials provided with the
-   distribution.
-
-   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-   You can contact the author at :
-   - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
-   - LZ4 source repository : http://code.google.com/p/lz4/
-*/
-
-
-
-/**************************************
-   Tuning Parameter
-**************************************/
-#define LZ4HC_DEFAULT_COMPRESSIONLEVEL 8
-
-
-/**************************************
-   Memory routines
-**************************************/
-#include <stdlib.h>   /* calloc, free */
-#define ALLOCATOR(s)  calloc(1,s)
-#define FREEMEM       free
-#include <string.h>   /* memset, memcpy */
-#define MEM_INIT      memset
-
-
-/**************************************
-   CPU Feature Detection
-**************************************/
-/* 32 or 64 bits ? */
-#if (defined(__x86_64__) || defined(_M_X64) || defined(_WIN64) \
-  || defined(__powerpc64__) || defined(__powerpc64le__) \
-  || defined(__ppc64__) || defined(__ppc64le__) \
-  || defined(__PPC64__) || defined(__PPC64LE__) \
-  || defined(__ia64) || defined(__itanium__) || defined(_M_IA64) )   /* Detects 64 bits mode */
-#  define LZ4_ARCH64 1
-#else
-#  define LZ4_ARCH64 0
-#endif
-
-/*
- * Little Endian or Big Endian ?
- * Overwrite the #define below if you know your architecture endianess
- */
-#include <stdlib.h>   /* Apparently required to detect endianess */
-#if defined (__GLIBC__)
-#  include <endian.h>
-#  if (__BYTE_ORDER == __BIG_ENDIAN)
-#     define LZ4_BIG_ENDIAN 1
-#  endif
-#elif (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || defined(_BIG_ENDIAN)) && !(defined(__LITTLE_ENDIAN__) || defined(__LITTLE_ENDIAN) || defined(_LITTLE_ENDIAN))
-#  define LZ4_BIG_ENDIAN 1
-#elif defined(__sparc) || defined(__sparc__) \
-   || defined(__powerpc__) || defined(__ppc__) || defined(__PPC__) \
-   || defined(__hpux)  || defined(__hppa) \
-   || defined(_MIPSEB) || defined(__s390__)
-#  define LZ4_BIG_ENDIAN 1
-#else
-/* Little Endian assumed. PDP Endian and other very rare endian format are unsupported. */
-#endif
-
-/*
- * Unaligned memory access is automatically enabled for "common" CPU, such as x86.
- * For others CPU, the compiler will be more cautious, and insert extra code to ensure aligned access is respected
- * If you know your target CPU supports unaligned memory access, you want to force this option manually to improve performance
- */
-#if defined(__ARM_FEATURE_UNALIGNED)
-#  define LZ4_FORCE_UNALIGNED_ACCESS 1
-#endif
-
-/* Define this parameter if your target system or compiler does not support hardware bit count */
-#if defined(_MSC_VER) && defined(_WIN32_WCE)            /* Visual Studio for Windows CE does not support Hardware bit count */
-#  define LZ4_FORCE_SW_BITCOUNT
-#endif
-
-
-/**************************************
- Compiler Options
-**************************************/
-#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)   /* C99 */
-/* "restrict" is a known keyword */
-#else
-#  define restrict /* Disable restrict */
-#endif
-
-#ifdef _MSC_VER    /* Visual Studio */
-#  define FORCE_INLINE static __forceinline
-#  include <intrin.h>                    /* For Visual 2005 */
-#  if LZ4_ARCH64   /* 64-bits */
-#    pragma intrinsic(_BitScanForward64) /* For Visual 2005 */
-#    pragma intrinsic(_BitScanReverse64) /* For Visual 2005 */
-#  else            /* 32-bits */
-#    pragma intrinsic(_BitScanForward)   /* For Visual 2005 */
-#    pragma intrinsic(_BitScanReverse)   /* For Visual 2005 */
-#  endif
-#  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
-#  pragma warning(disable : 4701)        /* disable: C4701: potentially uninitialized local variable used */
-#else
-#  ifdef __GNUC__
-#    define FORCE_INLINE static inline __attribute__((always_inline))
-#  else
-#    define FORCE_INLINE static inline
-#  endif
-#endif
-
-#ifdef _MSC_VER  /* Visual Studio */
-#  define lz4_bswap16(x) _byteswap_ushort(x)
-#else
-#  define lz4_bswap16(x)  ((unsigned short int) ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8)))
-#endif
-
-
-/**************************************
-   Includes
-**************************************/
-#include "lz4hc.h"
-#include "lz4.h"
-
-
-/**************************************
-   Basic Types
-**************************************/
-#if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)   /* C99 */
-# include <stdint.h>
-  typedef uint8_t  BYTE;
-  typedef uint16_t U16;
-  typedef uint32_t U32;
-  typedef  int32_t S32;
-  typedef uint64_t U64;
-#else
-  typedef unsigned char       BYTE;
-  typedef unsigned short      U16;
-  typedef unsigned int        U32;
-  typedef   signed int        S32;
-  typedef unsigned long long  U64;
-#endif
-
-#if defined(__GNUC__)  && !defined(LZ4_FORCE_UNALIGNED_ACCESS)
-#  define _PACKED __attribute__ ((packed))
-#else
-#  define _PACKED
-#endif
-
-#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
-#  ifdef __IBMC__
-#    pragma pack(1)
-#  else
-#    pragma pack(push, 1)
-#  endif
-#endif
-
-typedef struct _U16_S { U16 v; } _PACKED U16_S;
-typedef struct _U32_S { U32 v; } _PACKED U32_S;
-typedef struct _U64_S { U64 v; } _PACKED U64_S;
-
-#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
-#  pragma pack(pop)
-#endif
-
-#define A64(x) (((U64_S *)(x))->v)
-#define A32(x) (((U32_S *)(x))->v)
-#define A16(x) (((U16_S *)(x))->v)
-
-
-/**************************************
-   Constants
-**************************************/
-#define MINMATCH 4
-
-#define DICTIONARY_LOGSIZE 16
-#define MAXD (1<<DICTIONARY_LOGSIZE)
-#define MAXD_MASK ((U32)(MAXD - 1))
-#define MAX_DISTANCE (MAXD - 1)
-
-#define HASH_LOG (DICTIONARY_LOGSIZE-1)
-#define HASHTABLESIZE (1 << HASH_LOG)
-#define HASH_MASK (HASHTABLESIZE - 1)
-
-#define ML_BITS  4
-#define ML_MASK  (size_t)((1U<<ML_BITS)-1)
-#define RUN_BITS (8-ML_BITS)
-#define RUN_MASK ((1U<<RUN_BITS)-1)
-
-#define COPYLENGTH 8
-#define LASTLITERALS 5
-#define MFLIMIT (COPYLENGTH+MINMATCH)
-#define MINLENGTH (MFLIMIT+1)
-#define OPTIMAL_ML (int)((ML_MASK-1)+MINMATCH)
-
-#define KB *(1U<<10)
-#define MB *(1U<<20)
-#define GB *(1U<<30)
-
-
-/**************************************
-   Architecture-specific macros
-**************************************/
-#if LZ4_ARCH64   /* 64-bit */
-#  define STEPSIZE 8
-#  define LZ4_COPYSTEP(s,d)     A64(d) = A64(s); d+=8; s+=8;
-#  define LZ4_COPYPACKET(s,d)   LZ4_COPYSTEP(s,d)
-#  define AARCH A64
-#  define HTYPE                 U32
-#  define INITBASE(b,s)         const BYTE* const b = s
-#else            /* 32-bit */
-#  define STEPSIZE 4
-#  define LZ4_COPYSTEP(s,d)     A32(d) = A32(s); d+=4; s+=4;
-#  define LZ4_COPYPACKET(s,d)   LZ4_COPYSTEP(s,d); LZ4_COPYSTEP(s,d);
-#  define AARCH A32
-#  define HTYPE                 U32
-#  define INITBASE(b,s)         const BYTE* const b = s
-#endif
-
-#if defined(LZ4_BIG_ENDIAN)
-#  define LZ4_READ_LITTLEENDIAN_16(d,s,p) { U16 v = A16(p); v = lz4_bswap16(v); d = (s) - v; }
-#  define LZ4_WRITE_LITTLEENDIAN_16(p,i)  { U16 v = (U16)(i); v = lz4_bswap16(v); A16(p) = v; p+=2; }
-#else      /* Little Endian */
-#  define LZ4_READ_LITTLEENDIAN_16(d,s,p) { d = (s) - A16(p); }
-#  define LZ4_WRITE_LITTLEENDIAN_16(p,v)  { A16(p) = v; p+=2; }
-#endif
-
-
-/**************************************
-   Local Types
-**************************************/
-typedef struct
-{
-    const BYTE* inputBuffer;
-    const BYTE* base;
-    const BYTE* end;
-    HTYPE hashTable[HASHTABLESIZE];
-    U16 chainTable[MAXD];
-    const BYTE* nextToUpdate;
-} LZ4HC_Data_Structure;
-
-
-/**************************************
-   Macros
-**************************************/
-#define LZ4_WILDCOPY(s,d,e)    do { LZ4_COPYPACKET(s,d) } while (d<e);
-#define LZ4_BLINDCOPY(s,d,l)   { BYTE* e=d+l; LZ4_WILDCOPY(s,d,e); d=e; }
-#define HASH_FUNCTION(i)       (((i) * 2654435761U) >> ((MINMATCH*8)-HASH_LOG))
-#define HASH_VALUE(p)          HASH_FUNCTION(A32(p))
-#define HASH_POINTER(p)        (HashTable[HASH_VALUE(p)] + base)
-#define DELTANEXT(p)           chainTable[(size_t)(p) & MAXD_MASK]
-#define GETNEXT(p)             ((p) - (size_t)DELTANEXT(p))
-
-
-/**************************************
- Private functions
-**************************************/
-#if LZ4_ARCH64
-
-FORCE_INLINE int LZ4_NbCommonBytes (register U64 val)
-{
-#if defined(LZ4_BIG_ENDIAN)
-#  if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
-    unsigned long r = 0;
-    _BitScanReverse64( &r, val );
-    return (int)(r>>3);
-#  elif defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
-    return (__builtin_clzll(val) >> 3);
-#  else
-    int r;
-    if (!(val>>32)) { r=4; } else { r=0; val>>=32; }
-    if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
-    r += (!val);
-    return r;
-#  endif
-#else
-#  if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
-    unsigned long r = 0;
-    _BitScanForward64( &r, val );
-    return (int)(r>>3);
-#  elif defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
-    return (__builtin_ctzll(val) >> 3);
-#  else
-    static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 };
-    return DeBruijnBytePos[((U64)((val & -val) * 0x0218A392CDABBD3F)) >> 58];
-#  endif
-#endif
-}
-
-#else
-
-FORCE_INLINE int LZ4_NbCommonBytes (register U32 val)
-{
-#if defined(LZ4_BIG_ENDIAN)
-#  if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
-    unsigned long r;
-    _BitScanReverse( &r, val );
-    return (int)(r>>3);
-#  elif defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
-    return (__builtin_clz(val) >> 3);
-#  else
-    int r;
-    if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
-    r += (!val);
-    return r;
-#  endif
-#else
-#  if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
-    unsigned long r;
-    _BitScanForward( &r, val );
-    return (int)(r>>3);
-#  elif defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
-    return (__builtin_ctz(val) >> 3);
-#  else
-    static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 };
-    return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
-#  endif
-#endif
-}
-
-#endif
-
-
-int LZ4_sizeofStreamStateHC()
-{
-    return sizeof(LZ4HC_Data_Structure);
-}
-
-FORCE_INLINE void LZ4_initHC (LZ4HC_Data_Structure* hc4, const BYTE* base)
-{
-    MEM_INIT((void*)hc4->hashTable, 0, sizeof(hc4->hashTable));
-    MEM_INIT(hc4->chainTable, 0xFF, sizeof(hc4->chainTable));
-    hc4->nextToUpdate = base + 1;
-    hc4->base = base;
-    hc4->inputBuffer = base;
-    hc4->end = base;
-}
-
-int LZ4_resetStreamStateHC(void* state, const char* inputBuffer)
-{
-    if ((((size_t)state) & (sizeof(void*)-1)) != 0) return 1;   /* Error : pointer is not aligned for pointer (32 or 64 bits) */
-    LZ4_initHC((LZ4HC_Data_Structure*)state, (const BYTE*)inputBuffer);
-    return 0;
-}
-
-
-void* LZ4_createHC (const char* inputBuffer)
-{
-    void* hc4 = ALLOCATOR(sizeof(LZ4HC_Data_Structure));
-    LZ4_initHC ((LZ4HC_Data_Structure*)hc4, (const BYTE*)inputBuffer);
-    return hc4;
-}
-
-
-int LZ4_freeHC (void* LZ4HC_Data)
-{
-    FREEMEM(LZ4HC_Data);
-    return (0);
-}
-
-
-/* Update chains up to ip (excluded) */
-FORCE_INLINE void LZ4HC_Insert (LZ4HC_Data_Structure* hc4, const BYTE* ip)
-{
-    U16*   chainTable = hc4->chainTable;
-    HTYPE* HashTable  = hc4->hashTable;
-    INITBASE(base,hc4->base);
-
-    while(hc4->nextToUpdate < ip)
-    {
-        const BYTE* const p = hc4->nextToUpdate;
-        size_t delta = (p) - HASH_POINTER(p);
-        if (delta>MAX_DISTANCE) delta = MAX_DISTANCE;
-        DELTANEXT(p) = (U16)delta;
-        HashTable[HASH_VALUE(p)] = (HTYPE)((p) - base);
-        hc4->nextToUpdate++;
-    }
-}
-
-
-char* LZ4_slideInputBufferHC(void* LZ4HC_Data)
-{
-    LZ4HC_Data_Structure* hc4 = (LZ4HC_Data_Structure*)LZ4HC_Data;
-    U32 distance = (U32)(hc4->end - hc4->inputBuffer) - 64 KB;
-    distance = (distance >> 16) << 16;   /* Must be a multiple of 64 KB */
-    LZ4HC_Insert(hc4, hc4->end - MINMATCH);
-    memcpy((void*)(hc4->end - 64 KB - distance), (const void*)(hc4->end - 64 KB), 64 KB);
-    hc4->nextToUpdate -= distance;
-    hc4->base -= distance;
-    if ((U32)(hc4->inputBuffer - hc4->base) > 1 GB + 64 KB)   /* Avoid overflow */
-    {
-        int i;
-        hc4->base += 1 GB;
-        for (i=0; i<HASHTABLESIZE; i++) hc4->hashTable[i] -= 1 GB;
-    }
-    hc4->end -= distance;
-    return (char*)(hc4->end);
-}
-
-
-FORCE_INLINE size_t LZ4HC_CommonLength (const BYTE* p1, const BYTE* p2, const BYTE* const matchlimit)
-{
-    const BYTE* p1t = p1;
-
-    while (p1t<matchlimit-(STEPSIZE-1))
-    {
-        size_t diff = AARCH(p2) ^ AARCH(p1t);
-        if (!diff) { p1t+=STEPSIZE; p2+=STEPSIZE; continue; }
-        p1t += LZ4_NbCommonBytes(diff);
-        return (p1t - p1);
-    }
-    if (LZ4_ARCH64) if ((p1t<(matchlimit-3)) && (A32(p2) == A32(p1t))) { p1t+=4; p2+=4; }
-    if ((p1t<(matchlimit-1)) && (A16(p2) == A16(p1t))) { p1t+=2; p2+=2; }
-    if ((p1t<matchlimit) && (*p2 == *p1t)) p1t++;
-    return (p1t - p1);
-}
-
-
-FORCE_INLINE int LZ4HC_InsertAndFindBestMatch (LZ4HC_Data_Structure* hc4, const BYTE* ip, const BYTE* const matchlimit, const BYTE** matchpos, const int maxNbAttempts)
-{
-    U16* const chainTable = hc4->chainTable;
-    HTYPE* const HashTable = hc4->hashTable;
-    const BYTE* ref;
-    INITBASE(base,hc4->base);
-    int nbAttempts=maxNbAttempts;
-    size_t repl=0, ml=0;
-    U16 delta=0;  /* useless assignment, to remove an uninitialization warning */
-
-    /* HC4 match finder */
-    LZ4HC_Insert(hc4, ip);
-    ref = HASH_POINTER(ip);
-
-#define REPEAT_OPTIMIZATION
-#ifdef REPEAT_OPTIMIZATION
-    /* Detect repetitive sequences of length <= 4 */
-    if ((U32)(ip-ref) <= 4)        /* potential repetition */
-    {
-        if (A32(ref) == A32(ip))   /* confirmed */
-        {
-            delta = (U16)(ip-ref);
-            repl = ml  = LZ4HC_CommonLength(ip+MINMATCH, ref+MINMATCH, matchlimit) + MINMATCH;
-            *matchpos = ref;
-        }
-        ref = GETNEXT(ref);
-    }
-#endif
-
-    while (((U32)(ip-ref) <= MAX_DISTANCE) && (nbAttempts))
-    {
-        nbAttempts--;
-        if (*(ref+ml) == *(ip+ml))
-        if (A32(ref) == A32(ip))
-        {
-            size_t mlt = LZ4HC_CommonLength(ip+MINMATCH, ref+MINMATCH, matchlimit) + MINMATCH;
-            if (mlt > ml) { ml = mlt; *matchpos = ref; }
-        }
-        ref = GETNEXT(ref);
-    }
-
-#ifdef REPEAT_OPTIMIZATION
-    /* Complete table */
-    if (repl)
-    {
-        const BYTE* ptr = ip;
-        const BYTE* end;
-
-        end = ip + repl - (MINMATCH-1);
-        while(ptr < end-delta)
-        {
-            DELTANEXT(ptr) = delta;    /* Pre-Load */
-            ptr++;
-        }
-        do
-        {
-            DELTANEXT(ptr) = delta;
-            HashTable[HASH_VALUE(ptr)] = (HTYPE)((ptr) - base);     /* Head of chain */
-            ptr++;
-        } while(ptr < end);
-        hc4->nextToUpdate = end;
-    }
-#endif
-
-    return (int)ml;
-}
-
-
-FORCE_INLINE int LZ4HC_InsertAndGetWiderMatch (LZ4HC_Data_Structure* hc4, const BYTE* ip, const BYTE* startLimit, const BYTE* matchlimit, int longest, const BYTE** matchpos, const BYTE** startpos, const int maxNbAttempts)
-{
-    U16* const  chainTable = hc4->chainTable;
-    HTYPE* const HashTable = hc4->hashTable;
-    INITBASE(base,hc4->base);
-    const BYTE*  ref;
-    int nbAttempts = maxNbAttempts;
-    int delta = (int)(ip-startLimit);
-
-    /* First Match */
-    LZ4HC_Insert(hc4, ip);
-    ref = HASH_POINTER(ip);
-
-    while (((U32)(ip-ref) <= MAX_DISTANCE) && (nbAttempts))
-    {
-        nbAttempts--;
-        if (*(startLimit + longest) == *(ref - delta + longest))
-        if (A32(ref) == A32(ip))
-        {
-#if 1
-            const BYTE* reft = ref+MINMATCH;
-            const BYTE* ipt = ip+MINMATCH;
-            const BYTE* startt = ip;
-
-            while (ipt<matchlimit-(STEPSIZE-1))
-            {
-                size_t diff = AARCH(reft) ^ AARCH(ipt);
-                if (!diff) { ipt+=STEPSIZE; reft+=STEPSIZE; continue; }
-                ipt += LZ4_NbCommonBytes(diff);
-                goto _endCount;
-            }
-            if (LZ4_ARCH64) if ((ipt<(matchlimit-3)) && (A32(reft) == A32(ipt))) { ipt+=4; reft+=4; }
-            if ((ipt<(matchlimit-1)) && (A16(reft) == A16(ipt))) { ipt+=2; reft+=2; }
-            if ((ipt<matchlimit) && (*reft == *ipt)) ipt++;
-_endCount:
-            reft = ref;
-#else
-            /* Easier for code maintenance, but unfortunately slower too */
-            const BYTE* startt = ip;
-            const BYTE* reft = ref;
-            const BYTE* ipt = ip + MINMATCH + LZ4HC_CommonLength(ip+MINMATCH, ref+MINMATCH, matchlimit);
-#endif
-
-            while ((startt>startLimit) && (reft > hc4->inputBuffer) && (startt[-1] == reft[-1])) {startt--; reft--;}
-
-            if ((ipt-startt) > longest)
-            {
-                longest = (int)(ipt-startt);
-                *matchpos = reft;
-                *startpos = startt;
-            }
-        }
-        ref = GETNEXT(ref);
-    }
-
-    return longest;
-}
-
-
-typedef enum { noLimit = 0, limitedOutput = 1 } limitedOutput_directive;
-
-FORCE_INLINE int LZ4HC_encodeSequence (
-                       const BYTE** ip,
-                       BYTE** op,
-                       const BYTE** anchor,
-                       int matchLength,
-                       const BYTE* ref,
-                       limitedOutput_directive limitedOutputBuffer,
-                       BYTE* oend)
-{
-    int length;
-    BYTE* token;
-
-    /* Encode Literal length */
-    length = (int)(*ip - *anchor);
-    token = (*op)++;
-    if ((limitedOutputBuffer) && ((*op + length + (2 + 1 + LASTLITERALS) + (length>>8)) > oend)) return 1;   /* Check output limit */
-    if (length>=(int)RUN_MASK) { int len; *token=(RUN_MASK<<ML_BITS); len = length-RUN_MASK; for(; len > 254 ; len-=255) *(*op)++ = 255;  *(*op)++ = (BYTE)len; }
-    else *token = (BYTE)(length<<ML_BITS);
-
-    /* Copy Literals */
-    LZ4_BLINDCOPY(*anchor, *op, length);
-
-    /* Encode Offset */
-    LZ4_WRITE_LITTLEENDIAN_16(*op,(U16)(*ip-ref));
-
-    /* Encode MatchLength */
-    length = (int)(matchLength-MINMATCH);
-    if ((limitedOutputBuffer) && (*op + (1 + LASTLITERALS) + (length>>8) > oend)) return 1;   /* Check output limit */
-    if (length>=(int)ML_MASK) { *token+=ML_MASK; length-=ML_MASK; for(; length > 509 ; length-=510) { *(*op)++ = 255; *(*op)++ = 255; } if (length > 254) { length-=255; *(*op)++ = 255; } *(*op)++ = (BYTE)length; }
-    else *token += (BYTE)(length);
-
-    /* Prepare next loop */
-    *ip += matchLength;
-    *anchor = *ip;
-
-    return 0;
-}
-
-
-#define MAX_COMPRESSION_LEVEL 16
-static int LZ4HC_compress_generic (
-                 void* ctxvoid,
-                 const char* source,
-                 char* dest,
-                 int inputSize,
-                 int maxOutputSize,
-                 int compressionLevel,
-                 limitedOutput_directive limit
-                )
-{
-    LZ4HC_Data_Structure* ctx = (LZ4HC_Data_Structure*) ctxvoid;
-    const BYTE* ip = (const BYTE*) source;
-    const BYTE* anchor = ip;
-    const BYTE* const iend = ip + inputSize;
-    const BYTE* const mflimit = iend - MFLIMIT;
-    const BYTE* const matchlimit = (iend - LASTLITERALS);
-
-    BYTE* op = (BYTE*) dest;
-    BYTE* const oend = op + maxOutputSize;
-
-    const int maxNbAttempts = compressionLevel > MAX_COMPRESSION_LEVEL ? 1 << MAX_COMPRESSION_LEVEL : compressionLevel ? 1<<(compressionLevel-1) : 1<<LZ4HC_DEFAULT_COMPRESSIONLEVEL;
-    int   ml, ml2, ml3, ml0;
-    const BYTE* ref=NULL;
-    const BYTE* start2=NULL;
-    const BYTE* ref2=NULL;
-    const BYTE* start3=NULL;
-    const BYTE* ref3=NULL;
-    const BYTE* start0;
-    const BYTE* ref0;
-
-
-    /* Ensure blocks follow each other */
-    if (ip != ctx->end) return 0;
-    ctx->end += inputSize;
-
-    ip++;
-
-    /* Main Loop */
-    while (ip < mflimit)
-    {
-        ml = LZ4HC_InsertAndFindBestMatch (ctx, ip, matchlimit, (&ref), maxNbAttempts);
-        if (!ml) { ip++; continue; }
-
-        /* saved, in case we would skip too much */
-        start0 = ip;
-        ref0 = ref;
-        ml0 = ml;
-
-_Search2:
-        if (ip+ml < mflimit)
-            ml2 = LZ4HC_InsertAndGetWiderMatch(ctx, ip + ml - 2, ip + 1, matchlimit, ml, &ref2, &start2, maxNbAttempts);
-        else ml2 = ml;
-
-        if (ml2 == ml)  /* No better match */
-        {
-            if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) return 0;
-            continue;
-        }
-
-        if (start0 < ip)
-        {
-            if (start2 < ip + ml0)   /* empirical */
-            {
-                ip = start0;
-                ref = ref0;
-                ml = ml0;
-            }
-        }
-
-        /* Here, start0==ip */
-        if ((start2 - ip) < 3)   /* First Match too small : removed */
-        {
-            ml = ml2;
-            ip = start2;
-            ref =ref2;
-            goto _Search2;
-        }
-
-_Search3:
-        /*
-         * Currently we have :
-         * ml2 > ml1, and
-         * ip1+3 <= ip2 (usually < ip1+ml1)
-         */
-        if ((start2 - ip) < OPTIMAL_ML)
-        {
-            int correction;
-            int new_ml = ml;
-            if (new_ml > OPTIMAL_ML) new_ml = OPTIMAL_ML;
-            if (ip+new_ml > start2 + ml2 - MINMATCH) new_ml = (int)(start2 - ip) + ml2 - MINMATCH;
-            correction = new_ml - (int)(start2 - ip);
-            if (correction > 0)
-            {
-                start2 += correction;
-                ref2 += correction;
-                ml2 -= correction;
-            }
-        }
-        /* Now, we have start2 = ip+new_ml, with new_ml = min(ml, OPTIMAL_ML=18) */
-
-        if (start2 + ml2 < mflimit)
-            ml3 = LZ4HC_InsertAndGetWiderMatch(ctx, start2 + ml2 - 3, start2, matchlimit, ml2, &ref3, &start3, maxNbAttempts);
-        else ml3 = ml2;
-
-        if (ml3 == ml2) /* No better match : 2 sequences to encode */
-        {
-            /* ip & ref are known; Now for ml */
-            if (start2 < ip+ml)  ml = (int)(start2 - ip);
-            /* Now, encode 2 sequences */
-            if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) return 0;
-            ip = start2;
-            if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml2, ref2, limit, oend)) return 0;
-            continue;
-        }
-
-        if (start3 < ip+ml+3) /* Not enough space for match 2 : remove it */
-        {
-            if (start3 >= (ip+ml)) /* can write Seq1 immediately ==> Seq2 is removed, so Seq3 becomes Seq1 */
-            {
-                if (start2 < ip+ml)
-                {
-                    int correction = (int)(ip+ml - start2);
-                    start2 += correction;
-                    ref2 += correction;
-                    ml2 -= correction;
-                    if (ml2 < MINMATCH)
-                    {
-                        start2 = start3;
-                        ref2 = ref3;
-                        ml2 = ml3;
-                    }
-                }
-
-                if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) return 0;
-                ip  = start3;
-                ref = ref3;
-                ml  = ml3;
-
-                start0 = start2;
-                ref0 = ref2;
-                ml0 = ml2;
-                goto _Search2;
-            }
-
-            start2 = start3;
-            ref2 = ref3;
-            ml2 = ml3;
-            goto _Search3;
-        }
-
-        /*
-         * OK, now we have 3 ascending matches; let's write at least the first one
-         * ip & ref are known; Now for ml
-         */
-        if (start2 < ip+ml)
-        {
-            if ((start2 - ip) < (int)ML_MASK)
-            {
-                int correction;
-                if (ml > OPTIMAL_ML) ml = OPTIMAL_ML;
-                if (ip + ml > start2 + ml2 - MINMATCH) ml = (int)(start2 - ip) + ml2 - MINMATCH;
-                correction = ml - (int)(start2 - ip);
-                if (correction > 0)
-                {
-                    start2 += correction;
-                    ref2 += correction;
-                    ml2 -= correction;
-                }
-            }
-            else
-            {
-                ml = (int)(start2 - ip);
-            }
-        }
-        if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) return 0;
-
-        ip = start2;
-        ref = ref2;
-        ml = ml2;
-
-        start2 = start3;
-        ref2 = ref3;
-        ml2 = ml3;
-
-        goto _Search3;
-
-    }
-
-    /* Encode Last Literals */
-    {
-        int lastRun = (int)(iend - anchor);
-        if ((limit) && (((char*)op - dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize)) return 0;  /* Check output limit */
-        if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun > 254 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; }
-        else *op++ = (BYTE)(lastRun<<ML_BITS);
-        memcpy(op, anchor, iend - anchor);
-        op += iend-anchor;
-    }
-
-    /* End */
-    return (int) (((char*)op)-dest);
-}
-
-
-int LZ4_compressHC2(const char* source, char* dest, int inputSize, int compressionLevel)
-{
-    void* ctx = LZ4_createHC(source);
-    int result;
-    if (ctx==NULL) return 0;
-
-    result = LZ4HC_compress_generic (ctx, source, dest, inputSize, 0, compressionLevel, noLimit);
-
-    LZ4_freeHC(ctx);
-    return result;
-}
-
-int LZ4_compressHC(const char* source, char* dest, int inputSize) { return LZ4_compressHC2(source, dest, inputSize, 0); }
-
-int LZ4_compressHC2_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel)
-{
-    void* ctx = LZ4_createHC(source);
-    int result;
-    if (ctx==NULL) return 0;
-
-    result = LZ4HC_compress_generic (ctx, source, dest, inputSize, maxOutputSize, compressionLevel, limitedOutput);
-
-    LZ4_freeHC(ctx);
-    return result;
-}
-
-int LZ4_compressHC_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize)
-{
-    return LZ4_compressHC2_limitedOutput(source, dest, inputSize, maxOutputSize, 0);
-}
-
-
-/*****************************
-   Using external allocation
-*****************************/
-int LZ4_sizeofStateHC() { return sizeof(LZ4HC_Data_Structure); }
-
-
-int LZ4_compressHC2_withStateHC (void* state, const char* source, char* dest, int inputSize, int compressionLevel)
-{
-    if (((size_t)(state)&(sizeof(void*)-1)) != 0) return 0;   /* Error : state is not aligned for pointers (32 or 64 bits) */
-    LZ4_initHC ((LZ4HC_Data_Structure*)state, (const BYTE*)source);
-    return LZ4HC_compress_generic (state, source, dest, inputSize, 0, compressionLevel, noLimit);
-}
-
-int LZ4_compressHC_withStateHC (void* state, const char* source, char* dest, int inputSize)
-{ return LZ4_compressHC2_withStateHC (state, source, dest, inputSize, 0); }
-
-
-int LZ4_compressHC2_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel)
-{
-    if (((size_t)(state)&(sizeof(void*)-1)) != 0) return 0;   /* Error : state is not aligned for pointers (32 or 64 bits) */
-    LZ4_initHC ((LZ4HC_Data_Structure*)state, (const BYTE*)source);
-    return LZ4HC_compress_generic (state, source, dest, inputSize, maxOutputSize, compressionLevel, limitedOutput);
-}
-
-int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize)
-{ return LZ4_compressHC2_limitedOutput_withStateHC (state, source, dest, inputSize, maxOutputSize, 0); }
-
-
-/****************************
-   Stream functions
-****************************/
-
-int LZ4_compressHC_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize)
-{
-    return LZ4HC_compress_generic (LZ4HC_Data, source, dest, inputSize, 0, 0, noLimit);
-}
-
-int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel)
-{
-    return LZ4HC_compress_generic (LZ4HC_Data, source, dest, inputSize, 0, compressionLevel, noLimit);
-}
-
-int LZ4_compressHC_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize)
-{
-    return LZ4HC_compress_generic (LZ4HC_Data, source, dest, inputSize, maxOutputSize, 0, limitedOutput);
-}
-
-int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel)
-{
-    return LZ4HC_compress_generic (LZ4HC_Data, source, dest, inputSize, maxOutputSize, compressionLevel, limitedOutput);
-}
diff --git a/ext/lz4/lz4hc.h b/ext/lz4/lz4hc.h
deleted file mode 100644
index deb23940..00000000
--- a/ext/lz4/lz4hc.h
+++ /dev/null
@@ -1,173 +0,0 @@
-/*
-   LZ4 HC - High Compression Mode of LZ4
-   Header File
-   Copyright (C) 2011-2014, Yann Collet.
-   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
-
-   Redistribution and use in source and binary forms, with or without
-   modification, are permitted provided that the following conditions are
-   met:
-
-       * Redistributions of source code must retain the above copyright
-   notice, this list of conditions and the following disclaimer.
-       * Redistributions in binary form must reproduce the above
-   copyright notice, this list of conditions and the following disclaimer
-   in the documentation and/or other materials provided with the
-   distribution.
-
-   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-   You can contact the author at :
-   - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
-   - LZ4 source repository : http://code.google.com/p/lz4/
-*/
-#pragma once
-
-
-#if defined (__cplusplus)
-extern "C" {
-#endif
-
-
-int LZ4_compressHC (const char* source, char* dest, int inputSize);
-/*
-LZ4_compressHC :
-    return : the number of bytes in compressed buffer dest
-             or 0 if compression fails.
-    note : destination buffer must be already allocated.
-        To avoid any problem, size it to handle worst cases situations (input data not compressible)
-        Worst case size evaluation is provided by function LZ4_compressBound() (see "lz4.h")
-*/
-
-int LZ4_compressHC_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize);
-/*
-LZ4_compress_limitedOutput() :
-    Compress 'inputSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'.
-    If it cannot achieve it, compression will stop, and result of the function will be zero.
-    This function never writes outside of provided output buffer.
-
-    inputSize  : Max supported value is 1 GB
-    maxOutputSize : is maximum allowed size into the destination buffer (which must be already allocated)
-    return : the number of output bytes written in buffer 'dest'
-             or 0 if compression fails.
-*/
-
-
-int LZ4_compressHC2 (const char* source, char* dest, int inputSize, int compressionLevel);
-int LZ4_compressHC2_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
-/*
-    Same functions as above, but with programmable 'compressionLevel'.
-    Recommended values are between 4 and 9, although any value between 0 and 16 will work.
-    'compressionLevel'==0 means use default 'compressionLevel' value.
-    Values above 16 behave the same as 16.
-    Equivalent variants exist for all other compression functions below.
-*/
-
-/* Note :
-Decompression functions are provided within LZ4 source code (see "lz4.h") (BSD license)
-*/
-
-
-/**************************************
-   Using an external allocation
-**************************************/
-int LZ4_sizeofStateHC(void);
-int LZ4_compressHC_withStateHC               (void* state, const char* source, char* dest, int inputSize);
-int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
-
-int LZ4_compressHC2_withStateHC              (void* state, const char* source, char* dest, int inputSize, int compressionLevel);
-int LZ4_compressHC2_limitedOutput_withStateHC(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
-
-/*
-These functions are provided should you prefer to allocate memory for compression tables with your own allocation methods.
-To know how much memory must be allocated for the compression tables, use :
-int LZ4_sizeofStateHC();
-
-Note that tables must be aligned for pointer (32 or 64 bits), otherwise compression will fail (return code 0).
-
-The allocated memory can be provided to the compressions functions using 'void* state' parameter.
-LZ4_compress_withStateHC() and LZ4_compress_limitedOutput_withStateHC() are equivalent to previously described functions.
-They just use the externally allocated memory area instead of allocating their own (on stack, or on heap).
-*/
-
-
-/**************************************
-   Streaming Functions
-**************************************/
-/* Note : these streaming functions still follows the older model */
-void* LZ4_createHC (const char* inputBuffer);
-int   LZ4_compressHC_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize);
-int   LZ4_compressHC_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize);
-char* LZ4_slideInputBufferHC (void* LZ4HC_Data);
-int   LZ4_freeHC (void* LZ4HC_Data);
-
-int   LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel);
-int   LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
-
-/*
-These functions allow the compression of dependent blocks, where each block benefits from prior 64 KB within preceding blocks.
-In order to achieve this, it is necessary to start creating the LZ4HC Data Structure, thanks to the function :
-
-void* LZ4_createHC (const char* inputBuffer);
-The result of the function is the (void*) pointer on the LZ4HC Data Structure.
-This pointer will be needed in all other functions.
-If the pointer returned is NULL, then the allocation has failed, and compression must be aborted.
-The only parameter 'const char* inputBuffer' must, obviously, point at the beginning of input buffer.
-The input buffer must be already allocated, and size at least 192KB.
-'inputBuffer' will also be the 'const char* source' of the first block.
-
-All blocks are expected to lay next to each other within the input buffer, starting from 'inputBuffer'.
-To compress each block, use either LZ4_compressHC_continue() or LZ4_compressHC_limitedOutput_continue().
-Their behavior are identical to LZ4_compressHC() or LZ4_compressHC_limitedOutput(),
-but require the LZ4HC Data Structure as their first argument, and check that each block starts right after the previous one.
-If next block does not begin immediately after the previous one, the compression will fail (return 0).
-
-When it's no longer possible to lay the next block after the previous one (not enough space left into input buffer), a call to :
-char* LZ4_slideInputBufferHC(void* LZ4HC_Data);
-must be performed. It will typically copy the latest 64KB of input at the beginning of input buffer.
-Note that, for this function to work properly, minimum size of an input buffer must be 192KB.
-==> The memory position where the next input data block must start is provided as the result of the function.
-
-Compression can then resume, using LZ4_compressHC_continue() or LZ4_compressHC_limitedOutput_continue(), as usual.
-
-When compression is completed, a call to LZ4_freeHC() will release the memory used by the LZ4HC Data Structure.
-*/
-
-int LZ4_sizeofStreamStateHC(void);
-int LZ4_resetStreamStateHC(void* state, const char* inputBuffer);
-
-/*
-These functions achieve the same result as :
-void* LZ4_createHC (const char* inputBuffer);
-
-They are provided here to allow the user program to allocate memory using its own routines.
-
-To know how much space must be allocated, use LZ4_sizeofStreamStateHC();
-Note also that space must be aligned for pointers (32 or 64 bits).
-
-Once space is allocated, you must initialize it using : LZ4_resetStreamStateHC(void* state, const char* inputBuffer);
-void* state is a pointer to the space allocated.
-It must be aligned for pointers (32 or 64 bits), and be large enough.
-The parameter 'const char* inputBuffer' must, obviously, point at the beginning of input buffer.
-The input buffer must be already allocated, and size at least 192KB.
-'inputBuffer' will also be the 'const char* source' of the first block.
-
-The same space can be re-used multiple times, just by initializing it each time with LZ4_resetStreamState().
-return value of LZ4_resetStreamStateHC() must be 0 is OK.
-Any other value means there was an error (typically, state is not aligned for pointers (32 or 64 bits)).
-*/
-
-
-#if defined (__cplusplus)
-}
-#endif
diff --git a/make-mac.mk b/make-mac.mk
index db7ebfb6..784f4c6e 100644
--- a/make-mac.mk
+++ b/make-mac.mk
@@ -42,7 +42,7 @@ CXXFLAGS=$(CFLAGS) -fno-rtti
 
 include objects.mk
 
-OBJS+=node/BSDRoutingTable.o
+OBJS+=osnet/BSDRoutingTable.o
 
 all: one
 
diff --git a/node/Constants.hpp b/node/Constants.hpp
index 524a8428..7650de8b 100644
--- a/node/Constants.hpp
+++ b/node/Constants.hpp
@@ -156,6 +156,11 @@
 #define ZT_IF_MTU 2800
 
 /**
+ * Default interface metric for ZeroTier taps -- should be higher than physical ports
+ */
+#define ZT_DEFAULT_IF_METRIC 32768
+
+/**
  * Maximum number of packet fragments we'll support
  * 
  * The actual spec allows 16, but this is the most we'll support right
diff --git a/node/Defaults.cpp b/node/Defaults.cpp
index 4387c1ae..9176a414 100644
--- a/node/Defaults.cpp
+++ b/node/Defaults.cpp
@@ -52,57 +52,6 @@ static inline std::map< Identity,std::vector< std::pair<InetAddress,bool> > > _m
 	// Nothing special about a supernode... except that they are
 	// designated as such and trusted to provide WHOIS lookup.
 
-#ifdef ZT_USE_TESTNET
-
-	// If ZT_USE_TESTNET is defined we talk to test rather than live supernode
-	// instances. The testnet may not always be running, so this is probably not
-	// of any interest to users. Testnet servers run on port 7773 (UDP) and
-	// 773 (TCP).
-
-	// cthulhu.zerotier.com - New York, New York, USA
-	addrs.clear();
-	if (!id.fromString("0bfa76f104:0:aff4d4604f2a2538d414a1d69fc722a28bea049d52192aded117c28b0f6c1052db9d36c488c5fe5e2071f2def8f86b6db64db09e819f90fdaedbfcb9f3bcdef9"))
-		throw std::runtime_error("invalid identity in Defaults");
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("162.243.77.111",7773),false));
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("162.243.77.111",773),true));
-	sn[id] = addrs;
-
-	// nyarlathotep.zerotier.com - San Francisco, California, USA
-	addrs.clear();
-	if (!id.fromString("9f2b042cdb:0:8993f9348bb9642afa9a60995a35ef19817894fd0b6859201c0e56e399288867c8f0d01ae2858f9dc6f95eee6d42e2f6d08c44551404906b25679aa6db1faee7"))
-		throw std::runtime_error("invalid identity in Defaults");
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("198.199.97.220",7773),false));
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("198.199.97.220",773),true));
-	sn[id] = addrs;
-
-	// shub-niggurath.zerotier.com - Amsterdam, Netherlands
-	addrs.clear();
-	if (!id.fromString("916a4ca17d:0:b679a8d6761096ba4958fea0036dc4dbb76cb8cbf1ce9bc352cc594c3c24987bb3b30b5448d1f494f5e90a6cdaac9d28317cb4088780278ef20bc7c366cb214a"))
-		throw std::runtime_error("invalid identity in Defaults");
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("198.211.127.172",7773),false));
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("198.211.127.172",773),true));
-	sn[id] = addrs;
-
-	// yig.zerotier.com - Sydney, Australia
-	addrs.clear();
-	if (!id.fromString("3b62c7a69a:0:d967595a3b96d780151764e6ffb47af2fa8865f8e344fba4a684c10dd2e70014e26312f5b8a1590c13bfeb909a1fd35b96a84a8a43e0704cd8d01d9c2b791359"))
-		throw std::runtime_error("invalid identity in Defaults");
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("108.61.212.61",7773),false));
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("108.61.212.61",773),true));
-	sn[id] = addrs;
-
-	// shoggoth.zerotier.com - Tokyo, Japan
-	addrs.clear();
-	if (!id.fromString("345ad16512:0:9e796aec6e083726f45fbfdc10bcf18c0dc7a7914c9ce29f5eb5abcf41bfcb6b3698b68131d347235ae488804317df9c6102e2753841b973037d1e4685dce9fc"))
-		throw std::runtime_error("invalid identity in Defaults");
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("108.61.200.101",7773),false));
-	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("108.61.200.101",773),true));
-	sn[id] = addrs;
-
-#else
-
-	// Normally we use the live supernodes.
-
 	// cthulhu.zerotier.com - New York, New York, USA
 	addrs.clear();
 	if (!id.fromString("8acf059fe3:0:482f6ee5dfe902319b419de5bdc765209c0ecda38c4d6e4fcf0d33658398b4527dcd22f93112fb9befd02fd78bf7261b333fc105d192a623ca9e50fc60b374a5"))
@@ -143,8 +92,6 @@ static inline std::map< Identity,std::vector< std::pair<InetAddress,bool> > > _m
 	addrs.push_back(std::pair<InetAddress,bool>(InetAddress("108.61.200.101",443),true));
 	sn[id] = addrs;
 
-#endif
-
 	return sn;
 }
 
diff --git a/node/EthernetTap.hpp b/node/EthernetTap.hpp
index ba534a7e..87ab607d 100644
--- a/node/EthernetTap.hpp
+++ b/node/EthernetTap.hpp
@@ -171,14 +171,16 @@ public:
 	virtual void put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len) = 0;
 
 	/**
-	 * @return OS-specific device or connection name
+	 * @return OS-specific device or connection name (e.g. zt0, tap0, etc.)
 	 */
 	virtual std::string deviceName() const = 0;
 
 	/**
-	 * @return OS-internal persistent device ID or empty string if not applicable to this platform or not persistent
+	 * Change this device's user-visible name (if supported)
+	 *
+	 * @param friendlyName New name
 	 */
-	virtual std::string persistentId() const = 0;
+	virtual void setFriendlyName(const char *friendlyName) = 0;
 
 	/**
 	 * Fill or modify a set to contain multicast groups for this device
diff --git a/node/EthernetTapFactory.hpp b/node/EthernetTapFactory.hpp
index fde458f9..17d697f5 100644
--- a/node/EthernetTapFactory.hpp
+++ b/node/EthernetTapFactory.hpp
@@ -89,11 +89,12 @@ public:
 		void *arg) = 0;
 
 	/**
-	 * Close an ethernet tap device
+	 * Close an ethernet tap device and delete/free the tap object
 	 *
 	 * @param tap Tap instance
+	 * @param destroyPersistentDevices If true, destroy persistent device (on platforms where applicable)
 	 */
-	virtual void close(EthernetTap *tap) = 0;
+	virtual void close(EthernetTap *tap,bool destroyPersistentDevices) = 0;
 
 	/**
 	 * @return All currently open tap device names
diff --git a/node/Network.cpp b/node/Network.cpp
index f45d6c2f..43565e9f 100644
--- a/node/Network.cpp
+++ b/node/Network.cpp
@@ -37,12 +37,8 @@
 #include "Switch.hpp"
 #include "Packet.hpp"
 #include "Buffer.hpp"
-
-#ifdef __WINDOWS__
-#include "WindowsEthernetTap.hpp"
-#else
-#include "UnixEthernetTap.hpp"
-#endif
+#include "EthernetTap.hpp"
+#include "EthernetTapFactory.hpp"
 
 #define ZT_NETWORK_CERT_WRITE_BUF_SIZE 131072
 
@@ -69,26 +65,13 @@ Network::~Network()
 {
 	Thread::join(_setupThread);
 
-#ifdef __WINDOWS__
-	std::string devPersistentId;
-	if (_tap) {
-		devPersistentId = _tap->persistentId();
-		delete _tap;
-	}
-#else
 	if (_tap)
-		delete _tap;
-#endif
+		_r->tapFactory->close(_tap,_destroyOnDelete);
 
 	if (_destroyOnDelete) {
 		Utils::rm(std::string(_r->homePath + ZT_PATH_SEPARATOR_S + "networks.d" + ZT_PATH_SEPARATOR_S + idString() + ".conf"));
 		Utils::rm(std::string(_r->homePath + ZT_PATH_SEPARATOR_S + "networks.d" + ZT_PATH_SEPARATOR_S + idString() + ".mcerts"));
-#ifdef __WINDOWS__
-		if (devPersistentId.length())
-			WindowsEthernetTap::deletePersistentTapDevice(_r,devPersistentId.c_str());
-#endif
 	} else {
-		// Causes flush of membership certs to disk
 		clean();
 		_dumpMulticastCerts();
 	}
@@ -113,10 +96,16 @@ SharedPtr<Network> Network::newInstance(const RuntimeEnvironment *renv,NodeConfi
 	nw->_destroyOnDelete = false;
 	nw->_netconfFailure = NETCONF_FAILURE_NONE;
 
-	if (nw->controller() == renv->identity.address()) // netconf masters can't really join networks
+	if (nw->controller() == renv->identity.address()) // TODO: fix Switch to allow packets to self
 		throw std::runtime_error("cannot join a network for which I am the netconf master");
 
-	nw->_setupThread = Thread::start<Network>(nw.ptr());
+	try {
+		nw->_restoreState();
+		nw->requestConfiguration();
+	} catch ( ... ) {
+		TRACE("exception in network setup thread in _restoreState() or requestConfiguration()!");
+		nw->_lastConfigUpdate = 0; // call requestConfiguration() again
+	}
 
 	return nw;
 }
@@ -127,7 +116,7 @@ bool Network::updateMulticastGroups()
 	EthernetTap *t = _tap;
 	if (t) {
 		// Grab current groups from the local tap
-		bool updated = _tap->updateMulticastGroups(_multicastGroups);
+		bool updated = t->updateMulticastGroups(_multicastGroups);
 
 		// Merge in learned groups from any hosts bridged in behind us
 		for(std::map<MulticastGroup,uint64_t>::const_iterator mg(_bridgedMulticastGroups.begin());mg!=_bridgedMulticastGroups.end();++mg)
@@ -154,21 +143,11 @@ bool Network::setConfiguration(const Dictionary &conf,bool saveToDisk)
 {
 	Mutex::Lock _l(_lock);
 
-	EthernetTap *t = _tap;
-	if (!t) {
-		TRACE("BUG: setConfiguration() called while tap is null!");
-		return false; // can't accept config in initialization state
-	}
-
 	try {
-		SharedPtr<NetworkConfig> newConfig(new NetworkConfig(conf));
+		SharedPtr<NetworkConfig> newConfig(new NetworkConfig(conf)); // throws if invalid
 		if ((newConfig->networkId() == _id)&&(newConfig->issuedTo() == _r->identity.address())) {
 			_config = newConfig;
 
-			if (newConfig->staticIps().size())
-				t->setIps(newConfig->staticIps());
-			t->setDisplayName((std::string("ZeroTier One [") + newConfig->name() + "]").c_str());
-
 			_lastConfigUpdate = Utils::now();
 			_netconfFailure = NETCONF_FAILURE_NONE;
 
@@ -181,6 +160,17 @@ bool Network::setConfiguration(const Dictionary &conf,bool saveToDisk)
 				}
 			}
 
+			EthernetTap *t = _tap;
+			if (t) {
+				char fname[1024];
+				_mkNetworkFriendlyName(fname,sizeof(fname));
+				t->setIps(newConfig->staticIps());
+				t->setFriendlyName(fname);
+			} else {
+				if (!_setupThread)
+					_setupThread = Thread::start<Network>(this);
+			}
+
 			return true;
 		} else {
 			LOG("ignored invalid configuration for network %.16llx (configuration contains mismatched network ID or issued-to address)",(unsigned long long)_id);
@@ -196,9 +186,6 @@ bool Network::setConfiguration(const Dictionary &conf,bool saveToDisk)
 
 void Network::requestConfiguration()
 {
-	if (!_tap)
-		return; // don't bother requesting until we are initialized
-
 	if (controller() == _r->identity.address()) {
 		// netconf master cannot be a member of its own nets
 		LOG("unable to request network configuration for network %.16llx: I am the network master, cannot query self",(unsigned long long)_id);
@@ -346,51 +333,46 @@ void Network::_pushMembershipCertificate(const Address &peer,bool force,uint64_t
 	}
 }
 
+// Ethernet tap creation thread -- required on some platforms where tap
+// creation may be time consuming (e.g. Windows).
 void Network::threadMain()
 	throw()
 {
-	// Setup thread -- this exits when tap is constructed. It's here
-	// because opening the tap can take some time on some platforms.
+	char fname[1024],lcentry[128];
+	Utils::snprintf(lcentry,sizeof(lcentry),"_dev_for_%.16llx",(unsigned long long)_id);
 
+	EthernetTap *t;
 	try {
-#ifdef __WINDOWS__
-		// Windows tags interfaces by their network IDs, which are shoved into the
-		// registry to mark persistent instance of the tap device.
-		char tag[24];
-		Utils::snprintf(tag,sizeof(tag),"%.16llx",(unsigned long long)_id);
-		_tap = new WindowsEthernetTap(_r,tag,_mac,ZT_IF_MTU,&_CBhandleTapData,this);
-#else
-		// Unix tries to get the same device name next time, if possible.
-		std::string tagstr;
-		char lcentry[128];
-		Utils::snprintf(lcentry,sizeof(lcentry),"_dev_for_%.16llx",(unsigned long long)_id);
-		tagstr = _nc->getLocalConfig(lcentry);
-
-		const char *tag = (tagstr.length() > 0) ? tagstr.c_str() : (const char *)0;
-		_tap = new UnixEthernetTap(_r,tag,_mac,ZT_IF_MTU,&_CBhandleTapData,this);
-
-		std::string dn(_tap->deviceName());
-		if ((!tag)||(dn != tag))
+		std::string desiredDevice(_nc->getLocalConfig(lcentry));
+		_mkNetworkFriendlyName(fname,sizeof(fname));
+
+		t = _r->tapFactory->open(_mac,ZT_IF_MTU,ZT_DEFAULT_IF_METRIC,_id,(desiredDevice.length() > 0) ? desiredDevice.c_str() : (const char *)0,fname,_CBhandleTapData,this);
+
+		std::string dn(t->deviceName());
+		if ((dn.length())&&(dn != desiredDevice))
 			_nc->putLocalConfig(lcentry,dn);
-#endif
 	} catch (std::exception &exc) {
-		delete _tap;
-		_tap = (EthernetTap *)0;
+		delete t;
+		t = (EthernetTap *)0;
 		LOG("network %.16llx failed to initialize: %s",_id,exc.what());
 		_netconfFailure = NETCONF_FAILURE_INIT_FAILED;
 	} catch ( ... ) {
-		delete _tap;
-		_tap = (EthernetTap *)0;
+		delete t;
+		t = (EthernetTap *)0;
 		LOG("network %.16llx failed to initialize: unknown error",_id);
 		_netconfFailure = NETCONF_FAILURE_INIT_FAILED;
 	}
 
-	try {
-		_restoreState();
-		requestConfiguration();
-	} catch ( ... ) {
-		TRACE("BUG: exception in network setup thread in _restoreState() or requestConfiguration()!");
-		_lastConfigUpdate = 0; // call requestConfiguration() again
+	{
+		Mutex::Lock _l(_lock);
+		if (_tap) // the tap creation thread can technically be re-launched, though this isn't done right now
+			_r->tapFactory->close(_tap,_destroyOnDelete);
+		_tap = t;
+		if (t) {
+			if (_config)
+				t->setIps(_config->staticIps());
+			t->setEnabled(_enabled);
+		}
 	}
 }
 
@@ -423,14 +405,12 @@ void Network::setEnabled(bool enabled)
 {
 	Mutex::Lock _l(_lock);
 	_enabled = enabled;
-	// TODO: bring OS network device to "down" state if enabled == false
+	if (_tap)
+		_tap->setEnabled(enabled);
 }
 
 void Network::_restoreState()
 {
-	if (!_id)
-		return; // sanity check
-
 	Buffer<ZT_NETWORK_CERT_WRITE_BUF_SIZE> buf;
 
 	std::string idstr(idString());
@@ -448,7 +428,7 @@ void Network::_restoreState()
 		} else {
 			// If the conf file isn't present, "touch" it so we'll remember
 			// the existence of this network.
-			FILE *tmp = fopen(confPath.c_str(),"wb");
+			FILE *tmp = fopen(confPath.c_str(),"w");
 			if (tmp)
 				fclose(tmp);
 		}
diff --git a/node/Network.hpp b/node/Network.hpp
index 03b011f3..1d62bdf1 100644
--- a/node/Network.hpp
+++ b/node/Network.hpp
@@ -426,6 +426,14 @@ private:
 	void _restoreState();
 	void _dumpMulticastCerts();
 
+	inline void _mkNetworkFriendlyName(char *buf,unsigned int len)
+	{
+		// assumes _lock is locked
+		if (_config)
+			Utils::snprintf(buf,len,"ZeroTier One [%s]",_config->name().c_str());
+		else Utils::snprintf(buf,len,"ZeroTier One [%.16llx]",(unsigned long long)_id);
+	}
+
 	uint64_t _id;
 	NodeConfig *_nc; // parent NodeConfig object
 	MAC _mac; // local MAC address
@@ -439,8 +447,8 @@ private:
 	std::map<Address,CertificateOfMembership> _membershipCertificates;
 	std::map<Address,uint64_t> _lastPushedMembershipCertificate;
 
-	std::map<MAC,Address> _bridgeRoutes;
-	std::map<MulticastGroup,uint64_t> _bridgedMulticastGroups;
+	std::map<MAC,Address> _bridgeRoutes; // remote addresses where given MACs are reachable
+	std::map<MulticastGroup,uint64_t> _bridgedMulticastGroups; // multicast groups of interest on our side of the bridge
 
 	SharedPtr<NetworkConfig> _config;
 	volatile uint64_t _lastConfigUpdate;
diff --git a/node/Node.cpp b/node/Node.cpp
index 92b49d76..f2e6b3e4 100644
--- a/node/Node.cpp
+++ b/node/Node.cpp
@@ -67,7 +67,6 @@
 #include "EthernetTap.hpp"
 #include "CMWC4096.hpp"
 #include "NodeConfig.hpp"
-#include "SysEnv.hpp"
 #include "Network.hpp"
 #include "MulticastGroup.hpp"
 #include "Mutex.hpp"
@@ -77,6 +76,7 @@
 #include "Buffer.hpp"
 #include "IpcConnection.hpp"
 #include "AntiRecursion.hpp"
+#include "RoutingTable.hpp"
 
 namespace ZeroTier {
 
@@ -218,6 +218,7 @@ const char *Node::NodeControlClient::authTokenDefaultSystemPath()
 struct _NodeImpl
 {
 	RuntimeEnvironment renv;
+
 	unsigned int udpPort,tcpPort;
 	std::string reasonForTerminationStr;
 	volatile Node::ReasonForTermination reasonForTermination;
@@ -225,6 +226,7 @@ struct _NodeImpl
 	volatile bool running;
 	volatile bool resynchronize;
 
+	// This function performs final node tear-down
 	inline Node::ReasonForTermination terminate()
 	{
 		RuntimeEnvironment *_r = &renv;
@@ -238,16 +240,15 @@ struct _NodeImpl
 #ifndef __WINDOWS__
 		delete renv.netconfService;
 #endif
-		delete renv.updater;
-		delete renv.nc;
-		delete renv.sysEnv;
-		delete renv.topology;
-		delete renv.sm;
-		delete renv.sw;
-		delete renv.mc;
-		delete renv.antiRec;
-		delete renv.prng;
-		delete renv.log;
+		delete renv.updater;  renv.updater = (SoftwareUpdater *)0;
+		delete renv.nc;       renv.nc = (NodeConfig *)0;            // shut down all networks, close taps, etc.
+		delete renv.topology; renv.topology = (Topology *)0;        // now we no longer need routing info
+		delete renv.sm;       renv.sm = (SocketManager *)0;         // close all sockets
+		delete renv.sw;       renv.sw = (Switch *)0;                // order matters less from here down
+		delete renv.mc;       renv.mc = (Multicaster *)0;
+		delete renv.antiRec;  renv.antiRec = (AntiRecursion *)0;
+		delete renv.prng;     renv.prng = (CMWC4096 *)0;
+		delete renv.log;      renv.log = (Logger *)0;               // but stop logging last of all
 
 		return reasonForTermination;
 	}
@@ -260,7 +261,7 @@ struct _NodeImpl
 	}
 };
 
-#ifndef __WINDOWS__
+#ifndef __WINDOWS__ // "services" are not supported on Windows
 static void _netconfServiceMessageHandler(void *renv,Service &svc,const Dictionary &msg)
 {
 	if (!renv)
@@ -347,7 +348,13 @@ static void _netconfServiceMessageHandler(void *renv,Service &svc,const Dictiona
 }
 #endif // !__WINDOWS__
 
-Node::Node(const char *hp,unsigned int udpPort,unsigned int tcpPort,bool resetIdentity)
+Node::Node(
+	const char *hp,
+	EthernetTapFactory *tf,
+	RoutingTable *rt,
+	unsigned int udpPort,
+	unsigned int tcpPort,
+	bool resetIdentity)
 	throw() :
 	_impl(new _NodeImpl)
 {
@@ -357,6 +364,9 @@ Node::Node(const char *hp,unsigned int udpPort,unsigned int tcpPort,bool resetId
 		impl->renv.homePath = hp;
 	else impl->renv.homePath = ZT_DEFAULTS.defaultHomePath;
 
+	impl->renv.tapFactory = tf;
+	impl->renv.routingTable = rt;
+
 	if (resetIdentity) {
 		// Forget identity and peer database, peer keys, etc.
 		Utils::rm((impl->renv.homePath + ZT_PATH_SEPARATOR_S + "identity.public").c_str());
@@ -364,13 +374,14 @@ Node::Node(const char *hp,unsigned int udpPort,unsigned int tcpPort,bool resetId
 		Utils::rm((impl->renv.homePath + ZT_PATH_SEPARATOR_S + "peers.persist").c_str());
 
 		// Truncate network config information in networks.d but leave the files since we
-		// still want to remember any networks we have joined. This will force re-config.
+		// still want to remember any networks we have joined. This will force those networks
+		// to be reconfigured with our newly regenerated identity after startup.
 		std::string networksDotD(impl->renv.homePath + ZT_PATH_SEPARATOR_S + "networks.d");
 		std::map< std::string,bool > nwfiles(Utils::listDirectory(networksDotD.c_str()));
 		for(std::map<std::string,bool>::iterator nwf(nwfiles.begin());nwf!=nwfiles.end();++nwf) {
-			FILE *foo = fopen((networksDotD + ZT_PATH_SEPARATOR_S + nwf->first).c_str(),"w");
-			if (foo)
-				fclose(foo);
+			FILE *trun = fopen((networksDotD + ZT_PATH_SEPARATOR_S + nwf->first).c_str(),"w");
+			if (trun)
+				fclose(trun);
 		}
 	}
 
@@ -470,13 +481,11 @@ Node::ReasonForTermination Node::run()
 		}
 		Utils::lockDownFile(configAuthTokenPath.c_str(),false);
 
-		// Create the objects that make up runtime state.
 		_r->antiRec = new AntiRecursion();
 		_r->mc = new Multicaster();
 		_r->sw = new Switch(_r);
 		_r->sm = new SocketManager(impl->udpPort,impl->tcpPort,&_CBztTraffic,_r);
 		_r->topology = new Topology(_r,Utils::fileExists((_r->homePath + ZT_PATH_SEPARATOR_S + "iddb.d").c_str()));
-		_r->sysEnv = new SysEnv();
 		try {
 			_r->nc = new NodeConfig(_r,configAuthToken.c_str());
 		} catch (std::exception &exc) {
@@ -568,7 +577,7 @@ Node::ReasonForTermination Node::run()
 			// If our network environment looks like it changed, resynchronize.
 			if ((resynchronize)||((now - lastNetworkFingerprintCheck) >= ZT_NETWORK_FINGERPRINT_CHECK_DELAY)) {
 				lastNetworkFingerprintCheck = now;
-				uint64_t fp = _r->sysEnv->getNetworkConfigurationFingerprint(_r->nc->networkTapDeviceNames());
+				uint64_t fp = _r->routingTable->networkEnvironmentFingerprint(_r->nc->networkTapDeviceNames());
 				if (fp != networkConfigurationFingerprint) {
 					LOG("netconf fingerprint change: %.16llx != %.16llx, resyncing with network",networkConfigurationFingerprint,fp);
 					networkConfigurationFingerprint = fp;
@@ -588,7 +597,7 @@ Node::ReasonForTermination Node::run()
 			}
 
 			if (resynchronize) {
-				_r->tcpTunnelingEnabled = false; // turn off TCP tunneling master switch at first
+				_r->tcpTunnelingEnabled = false; // turn off TCP tunneling master switch at first, will be reenabled on persistent UDP failure
 				_r->timeOfLastResynchronize = now;
 			}
 
@@ -643,17 +652,15 @@ Node::ReasonForTermination Node::run()
 
 				/* Periodically ping all our non-stale direct peers unless we're a supernode.
 				 * Supernodes only ping each other (which is done above). */
-				if (!_r->topology->amSupernode()) {
-					if ((now - lastPingCheck) >= ZT_PING_CHECK_DELAY) {
-						lastPingCheck = now;
-						try {
-							_r->topology->eachPeer(Topology::PingPeersThatNeedPing(_r,now));
-							_r->topology->eachPeer(Topology::OpenPeersThatNeedFirewallOpener(_r,now));
-						} catch (std::exception &exc) {
-							LOG("unexpected exception running ping check cycle: %s",exc.what());
-						} catch ( ... ) {
-							LOG("unexpected exception running ping check cycle: (unkonwn)");
-						}
+				if ((!_r->topology->amSupernode())&&((now - lastPingCheck) >= ZT_PING_CHECK_DELAY)) {
+					lastPingCheck = now;
+					try {
+						_r->topology->eachPeer(Topology::PingPeersThatNeedPing(_r,now));
+						_r->topology->eachPeer(Topology::OpenPeersThatNeedFirewallOpener(_r,now));
+					} catch (std::exception &exc) {
+						LOG("unexpected exception running ping check cycle: %s",exc.what());
+					} catch ( ... ) {
+						LOG("unexpected exception running ping check cycle: (unkonwn)");
 					}
 				}
 			}
diff --git a/node/Node.hpp b/node/Node.hpp
index cc2886e7..6cc3ef40 100644
--- a/node/Node.hpp
+++ b/node/Node.hpp
@@ -33,6 +33,9 @@
 
 namespace ZeroTier {
 
+class EthernetTapFactory;
+class RoutingTable;
+
 /**
  * A ZeroTier One node
  *
@@ -150,14 +153,25 @@ public:
 	/**
 	 * Create a new node
 	 *
-	 * The node is not executed until run() is called.
+	 * The node is not executed until run() is called. The supplied tap factory
+	 * and routing table must not be freed until the node is no longer
+	 * executing. Node does not delete these objects, so the caller still owns
+	 * them.
 	 *
-	 * @param hp Home directory path or NULL for system-wide default for this platform (default: NULL)
-	 * @param udpPort UDP port or 0 to disable (default: 9993)
-	 * @param tcpPort TCP port or 0 to disable (default: 0)
-	 * @param resetIdentity If true, delete identity before starting and regenerate (default: false)
+	 * @param hp Home directory path or NULL for system-wide default for this platform
+	 * @param tf Ethernet tap factory for platform network stack
+	 * @param rt Routing table interface for platform network stack
+	 * @param udpPort UDP port or 0 to disable
+	 * @param tcpPort TCP port or 0 to disable
+	 * @param resetIdentity If true, delete identity before starting and regenerate
 	 */
-	Node(const char *hp = (const char *)0,unsigned int udpPort = 9993,unsigned int tcpPort = 0,bool resetIdentity = false)
+	Node(
+		const char *hp,
+		EthernetTapFactory *tf,
+		RoutingTable *rt,
+		unsigned int udpPort,
+		unsigned int tcpPort,
+		bool resetIdentity)
 		throw();
 
 	~Node();
diff --git a/node/NodeConfig.hpp b/node/NodeConfig.hpp
index ada135ac..b9bc8f5f 100644
--- a/node/NodeConfig.hpp
+++ b/node/NodeConfig.hpp
@@ -120,16 +120,16 @@ public:
 	}
 
 	/**
-	 * @return Set of network tap device names from our virtual networks (not other taps on system)
+	 * @return Sorted vector of network tap device names from our virtual networks (not other taps on system)
 	 */
-	inline std::set<std::string> networkTapDeviceNames() const
+	inline std::vector<std::string> networkTapDeviceNames() const
 	{
-		std::set<std::string> tapDevs;
+		std::vector<std::string> tapDevs;
 		Mutex::Lock _l(_networks_m);
 		for(std::map< uint64_t,SharedPtr<Network> >::const_iterator n(_networks.begin());n!=_networks.end();++n) {
 			std::string dn(n->second->tapDeviceName());
 			if (dn.length())
-				tapDevs.insert(dn);
+				tapDevs.push_back(dn);
 		}
 		return tapDevs;
 	}
diff --git a/node/RuntimeEnvironment.hpp b/node/RuntimeEnvironment.hpp
index 8887b081..78d950ce 100644
--- a/node/RuntimeEnvironment.hpp
+++ b/node/RuntimeEnvironment.hpp
@@ -39,7 +39,6 @@ class NodeConfig;
 class Logger;
 class Switch;
 class Topology;
-class SysEnv;
 class CMWC4096;
 class Service;
 class Node;
@@ -47,6 +46,8 @@ class Multicaster;
 class SoftwareUpdater;
 class SocketManager;
 class AntiRecursion;
+class EthernetTapFactory;
+class RoutingTable;
 
 /**
  * Holds global state for an instance of ZeroTier::Node
@@ -68,6 +69,8 @@ public:
 		tcpTunnelingEnabled(false),
 		timeOfLastResynchronize(0),
 		timeOfLastPacketReceived(0),
+		tapFactory((EthernetTapFactory *)0),
+		routingTable((RoutingTable *)0),
 		log((Logger *)0),
 		prng((CMWC4096 *)0),
 		antiRec((AntiRecursion *)0),
@@ -75,7 +78,6 @@ public:
 		sw((Switch *)0),
 		sm((SocketManager *)0),
 		topology((Topology *)0),
-		sysEnv((SysEnv *)0),
 		nc((NodeConfig *)0),
 		updater((SoftwareUpdater *)0)
 #ifndef __WINDOWS__
@@ -103,6 +105,10 @@ public:
 	// via an ugly const_cast<>.
 	volatile uint64_t timeOfLastPacketReceived;
 
+	// These are passed in from outside and are not created or deleted by the ZeroTier node core
+	EthernetTapFactory *tapFactory;
+	RoutingTable *routingTable;
+
 	/*
 	 * Order matters a bit here. These are constructed in this order
 	 * and then deleted in the opposite order on Node exit. The order ensures
@@ -118,7 +124,6 @@ public:
 	Switch *sw;
 	SocketManager *sm;
 	Topology *topology;
-	SysEnv *sysEnv;
 	NodeConfig *nc;
 	Node *node;
 	SoftwareUpdater *updater; // null if software updates are not enabled
diff --git a/node/SysEnv.cpp b/node/SysEnv.cpp
deleted file mode 100644
index fdf52f11..00000000
--- a/node/SysEnv.cpp
+++ /dev/null
@@ -1,224 +0,0 @@
-/*
- * ZeroTier One - Global Peer to Peer Ethernet
- * Copyright (C) 2011-2014  ZeroTier Networks LLC
- *
- * 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/>.
- *
- * --
- *
- * ZeroTier may be used and distributed under the terms of the GPLv3, which
- * are available at: http://www.gnu.org/licenses/gpl-3.0.html
- *
- * If you would like to embed ZeroTier into a commercial application or
- * redistribute it in a modified binary form, please contact ZeroTier Networks
- * LLC. Start here: http://www.zerotier.com/
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <fcntl.h>
-#include <errno.h>
-#include <sys/types.h>
-
-#include <set>
-#include <string>
-
-#include "Constants.hpp"
-#include "SysEnv.hpp"
-#include "Utils.hpp"
-#include "RuntimeEnvironment.hpp"
-#include "NodeConfig.hpp"
-
-#ifdef __UNIX_LIKE__
-#include <arpa/inet.h>
-#include <sys/socket.h>
-#include <unistd.h>
-#include <signal.h>
-#endif
-
-#ifdef __APPLE__
-#include <sys/sysctl.h>
-#include <sys/uio.h>
-#include <sys/param.h>
-#include <net/route.h>
-#endif
-
-#ifdef __WINDOWS__
-#include <Windows.h>
-#include <WinSock2.h>
-#endif
-
-namespace ZeroTier {
-
-SysEnv::SysEnv()
-{
-}
-
-SysEnv::~SysEnv()
-{
-}
-
-#ifdef __APPLE__
-
-uint64_t SysEnv::getNetworkConfigurationFingerprint(const std::set<std::string> &ignoreDevices)
-{
-	int mib[6];
-	size_t needed;
-	uint64_t fingerprint = 5381; // djb2 hash algorithm is used below
-
-	// Right now this just scans for changes in default routes. This is not
-	// totally robust -- it will miss cases where we switch from one 10.0.0.0/24
-	// network with gateway .1 to another -- but most of the time it'll pick
-	// up shifts in connectivity. Combined with sleep/wake detection this seems
-	// pretty solid so far on Mac for detecting when you change locations.
-
-	mib[0] = CTL_NET;
-	mib[1] = PF_ROUTE;
-	mib[2] = 0;
-	mib[3] = AF_UNSPEC;
-	mib[4] = NET_RT_DUMP;
-	mib[5] = 0;
-	if (!sysctl(mib,6,NULL,&needed,NULL,0)) {
-		char *buf = (char *)malloc(needed);
-		if (buf) {
-			if (!sysctl(mib,6,buf,&needed,NULL,0)) {
-		    struct rt_msghdr *rtm;
-				for(char *next=buf,*end=buf+needed;next<end;) {
-					rtm = (struct rt_msghdr *)next;
-					char *saptr = (char *)(rtm + 1);
-					char *saend = next + rtm->rtm_msglen;
-					if (((rtm->rtm_addrs & RTA_DST))&&((rtm->rtm_addrs & RTA_GATEWAY))) {
-						int sano = 0;
-						struct sockaddr *dst = (struct sockaddr *)0;
-						struct sockaddr *gateway = (struct sockaddr *)0;
-						while (saptr < saend) {
-							struct sockaddr *sa = (struct sockaddr *)saptr;
-							if (!sa->sa_len)
-								break;
-							if (sano == 0)
-								dst = sa;
-							else if (sano == 1)
-								gateway = sa;
-							else if (sano > 1)
-								break;
-							++sano;
-							saptr += sa->sa_len;
-						}
-						if ((dst)&&(gateway)) {
-							if ((dst->sa_family == AF_INET)&&(gateway->sa_family == AF_INET)&&(!((struct sockaddr_in *)dst)->sin_addr.s_addr)) {
-								fingerprint = ((fingerprint << 5) + fingerprint) + (uint64_t)((struct sockaddr_in *)gateway)->sin_addr.s_addr;
-							} else if ((dst->sa_family == AF_INET6)&&(gateway->sa_family == AF_INET6)&&(Utils::isZero(((struct sockaddr_in6 *)dst)->sin6_addr.s6_addr,16))) {
-								for(unsigned int i=0;i<16;++i)
-									fingerprint = ((fingerprint << 5) + fingerprint) + (uint64_t)((struct sockaddr_in6 *)gateway)->sin6_addr.s6_addr[i];
-							}
-						}
-					}
-					next = saend;
-				}
-			}
-			free(buf);
-		}
-	}
-
-	return fingerprint;
-}
-
-#endif // __APPLE__
-
-#if defined(__linux__) || defined(linux) || defined(__LINUX__) || defined(__linux)
-
-uint64_t SysEnv::getNetworkConfigurationFingerprint(const std::set<std::string> &ignoreDevices)
-{
-	char buf[16384];
-	uint64_t fingerprint = 5381; // djb2 hash algorithm is used below
-	char *t1,*t2;
-
-	try {
-		// Include default IPv4 route if available
-		int fd = open("/proc/net/route",O_RDONLY);
-		if (fd > 0) {
-			long n = read(fd,buf,sizeof(buf) - 1);
-			::close(fd);
-			if (n > 0) {
-				buf[n] = 0;
-				for(char *line=strtok_r(buf,"\r\n",&t1);(line);line=strtok_r((char *)0,"\r\n",&t1)) {
-					int fno = 0;
-					for(char *field=strtok_r(line," \t",&t2);(field);field=strtok_r((char *)0," \t",&t2)) {
-						if (fno == 0) { // device name
-							if ((ignoreDevices.count(std::string(field)))||(!strcmp(field,"lo")))
-								break;
-						} else if ((fno == 1)||(fno == 2)) { // destination, gateway
-							if (strlen(field) == 8) { // ignore header junk, use only hex route info
-								while (*field)
-									fingerprint = ((fingerprint << 5) + fingerprint) + (uint64_t)*(field++);
-							}
-						} else if (fno > 2)
-							break;
-						++fno;
-					}
-				}
-			}
-		}
-
-		// Include IPs of IPv6 enabled interfaces if available
-		fd = open("/proc/net/if_inet6",O_RDONLY);
-		if (fd > 0) {
-			long n = read(fd,buf,sizeof(buf) - 1);
-			::close(fd);
-			if (n > 0) {
-				buf[n] = 0;
-				for(char *line=strtok_r(buf,"\r\n",&t1);(line);line=strtok_r((char *)0,"\r\n",&t1)) {
-					int fno = 0;
-					const char *v6ip = (const char *)0;
-					const char *devname = (const char *)0;
-					for(char *field=strtok_r(line," \t",&t2);(field);field=strtok_r((char *)0," \t",&t2)) {
-						switch(fno) {
-							case 0:
-								v6ip = field;
-								break;
-							case 5:
-								devname = field;
-								break;
-						}
-						++fno;
-					}
-
-					if ((v6ip)&&(devname)) {
-						if ((!(ignoreDevices.count(std::string(devname))))&&(strcmp(devname,"lo"))) {
-							while (*v6ip)
-								fingerprint = ((fingerprint << 5) + fingerprint) + (uint64_t)*(v6ip++);
-						}
-					}
-				}
-			}
-		}
-	} catch ( ... ) {}
-
-	return fingerprint;
-}
-
-#endif // __linux__
-
-#ifdef __WINDOWS__
-
-uint64_t SysEnv::getNetworkConfigurationFingerprint(const std::set<std::string> &ignoreDevices)
-{
-	// TODO: windows version
-	return 1;
-}
-
-#endif // __WINDOWS__
-
-} // namespace ZeroTier
diff --git a/node/SysEnv.hpp b/node/SysEnv.hpp
deleted file mode 100644
index dc73101b..00000000
--- a/node/SysEnv.hpp
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
- * ZeroTier One - Global Peer to Peer Ethernet
- * Copyright (C) 2011-2014  ZeroTier Networks LLC
- *
- * 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/>.
- *
- * --
- *
- * ZeroTier may be used and distributed under the terms of the GPLv3, which
- * are available at: http://www.gnu.org/licenses/gpl-3.0.html
- *
- * If you would like to embed ZeroTier into a commercial application or
- * redistribute it in a modified binary form, please contact ZeroTier Networks
- * LLC. Start here: http://www.zerotier.com/
- */
-
-#ifndef ZT_SYSENV_HPP
-#define ZT_SYSENV_HPP
-
-#include <stdint.h>
-
-#include <set>
-
-#include "NonCopyable.hpp"
-
-namespace ZeroTier {
-
-class RuntimeEnvironment;
-
-/**
- * Local system environment monitoring utilities
- */
-class SysEnv : NonCopyable
-{
-public:
-	SysEnv();
-	~SysEnv();
-
-	/**
-	 * This computes a CRC-type code from gathered information about your network settings
-	 *
-	 * @param ignoreDevices Ignore these local network devices by OS-specific name (e.g. our taps)
-	 * @return Fingerprint of currently running network environment
-	 */
-	uint64_t getNetworkConfigurationFingerprint(const std::set<std::string> &ignoreDevices);
-};
-
-} // namespace ZeroTier
-
-#endif
diff --git a/node/Thread.hpp b/node/Thread.hpp
index 6426d5bb..a796af33 100644
--- a/node/Thread.hpp
+++ b/node/Thread.hpp
@@ -87,6 +87,8 @@ public:
 			CancelSynchronousIo(t._th);

 	}

 

+	inline operator bool() const throw() { return (_th != NULL); }

+

 private:

 	HANDLE _th;

 	DWORD _tid;

@@ -123,18 +125,21 @@ public:
 		throw()

 	{

 		memset(&_tid,0,sizeof(_tid));

+		_started = false;

 	}

 

 	Thread(const Thread &t)

 		throw()

 	{

 		memcpy(&_tid,&(t._tid),sizeof(_tid));

+		_started = t._started;

 	}

 

 	inline Thread &operator=(const Thread &t)

 		throw()

 	{

 		memcpy(&_tid,&(t._tid),sizeof(_tid));

+		_started = t._started;

 		return *this;

 	}

 

@@ -151,19 +156,21 @@ public:
 		throw(std::runtime_error)

 	{

 		Thread t;

+		t._started = true;

 		if (pthread_create(&t._tid,(const pthread_attr_t *)0,&___zt_threadMain<C>,instance))

 			throw std::runtime_error("pthread_create() failed, unable to create thread");

 		return t;

 	}

 

 	/**

-	 * Join to a thread, waiting for it to terminate

+	 * Join to a thread, waiting for it to terminate (does nothing on null Thread values)

 	 *

 	 * @param t Thread to join

 	 */

 	static inline void join(const Thread &t)

 	{

-		pthread_join(t._tid,(void **)0);

+		if (t._started)

+			pthread_join(t._tid,(void **)0);

 	}

 

 	/**

@@ -171,13 +178,13 @@ public:
 	 *

 	 * @param ms Number of milliseconds to sleep

 	 */

-	static inline void sleep(unsigned long ms)

-	{

-		usleep(ms * 1000);

-	}

+	static inline void sleep(unsigned long ms) { usleep(ms * 1000); }

+

+	inline operator bool() const throw() { return (_started); }

 

 private:

 	pthread_t _tid;

+	volatile bool _started;

 };

 

 } // namespace ZeroTier

diff --git a/objects.mk b/objects.mk
index 4a6e7b83..24a54683 100644
--- a/objects.mk
+++ b/objects.mk
@@ -1,5 +1,4 @@
 OBJS=\
-	ext/lz4/lz4hc.o \
 	ext/lz4/lz4.o \
 	node/C25519.o \
 	node/CertificateOfMembership.o \
@@ -26,7 +25,6 @@ OBJS=\
 	node/SoftwareUpdater.o \
 	node/SHA512.o \
 	node/Switch.o \
-	node/SysEnv.o \
 	node/TcpSocket.o \
 	node/Topology.o \
 	node/UdpSocket.o \
diff --git a/osnet/BSDRoutingTable.cpp b/osnet/BSDRoutingTable.cpp
index fede9cce..63dd5cef 100644
--- a/osnet/BSDRoutingTable.cpp
+++ b/osnet/BSDRoutingTable.cpp
@@ -43,7 +43,7 @@
 #include <algorithm>
 #include <utility>
 
-#include "../Constants.hpp"
+#include "../node/Constants.hpp"
 #include "BSDRoutingTable.hpp"
 
 // All I wanted was the bloody rounting table. I didn't expect the Spanish inquisition.
diff --git a/osnet/BSDRoutingTable.hpp b/osnet/BSDRoutingTable.hpp
index c0e98943..b498d5ce 100644
--- a/osnet/BSDRoutingTable.hpp
+++ b/osnet/BSDRoutingTable.hpp
@@ -28,7 +28,7 @@
 #ifndef ZT_BSDROUTINGTABLE_HPP
 #define ZT_BSDROUTINGTABLE_HPP
 
-#include "../RoutingTable.hpp"
+#include "../node/RoutingTable.hpp"
 
 namespace ZeroTier {
 
diff --git a/osnet/LinuxEthernetTap.cpp b/osnet/LinuxEthernetTap.cpp
index 0b0c1c4f..d77d56c0 100644
--- a/osnet/LinuxEthernetTap.cpp
+++ b/osnet/LinuxEthernetTap.cpp
@@ -355,9 +355,8 @@ std::string LinuxEthernetTap::deviceName() const
 	return _dev;
 }
 
-std::string LinuxEthernetTap::persistentId() const
+void LinuxEthernetTap::setFriendlyName(const char *friendlyName)
 {
-	return std::string();
 }
 
 bool LinuxEthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
diff --git a/osnet/LinuxEthernetTap.hpp b/osnet/LinuxEthernetTap.hpp
index e6aea2ec..f74fdf86 100644
--- a/osnet/LinuxEthernetTap.hpp
+++ b/osnet/LinuxEthernetTap.hpp
@@ -64,7 +64,7 @@ public:
 	virtual std::set<InetAddress> ips() const;
 	virtual void put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len);
 	virtual std::string deviceName() const;
-	virtual std::string persistentId() const;
+	virtual void setFriendlyName(const char *friendlyName);
 	virtual bool updateMulticastGroups(std::set<MulticastGroup> &groups);
 
 	void threadMain()
diff --git a/osnet/LinuxEthernetTapFactory.cpp b/osnet/LinuxEthernetTapFactory.cpp
index fccb6bd5..01633abb 100644
--- a/osnet/LinuxEthernetTapFactory.cpp
+++ b/osnet/LinuxEthernetTapFactory.cpp
@@ -57,7 +57,7 @@ EthernetTap *LinuxEthernetTapFactory::open(
 	return t;
 }
 
-void LinuxEthernetTapFactory::close(EthernetTap *tap)
+void LinuxEthernetTapFactory::close(EthernetTap *tap,bool destroyPersistentDevices)
 {
 	{
 		Mutex::Lock _l(_devices_m);
diff --git a/osnet/LinuxEthernetTapFactory.hpp b/osnet/LinuxEthernetTapFactory.hpp
index a5d13216..695fe52e 100644
--- a/osnet/LinuxEthernetTapFactory.hpp
+++ b/osnet/LinuxEthernetTapFactory.hpp
@@ -51,7 +51,7 @@ public:
 		const char *friendlyName,
 		void (*handler)(void *,const MAC &,const MAC &,unsigned int,const Buffer<4096> &),
 		void *arg);
-	virtual void close(EthernetTap *tap);
+	virtual void close(EthernetTap *tap,bool destroyPersistentDevices);
 	virtual std::vector<std::string> allTapDeviceNames() const;
 
 private:
diff --git a/osnet/OSXEthernetTap.cpp b/osnet/OSXEthernetTap.cpp
index 1e2ddbed..164b24a2 100644
--- a/osnet/OSXEthernetTap.cpp
+++ b/osnet/OSXEthernetTap.cpp
@@ -529,9 +529,8 @@ std::string OSXEthernetTap::deviceName() const
 	return _dev;
 }
 
-std::string OSXEthernetTap::persistentId() const
+void OSXEthernetTap::setFriendlyName(const char *friendlyName)
 {
-	return std::string();
 }
 
 bool OSXEthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
diff --git a/osnet/OSXEthernetTap.hpp b/osnet/OSXEthernetTap.hpp
index 7ca63730..680fef15 100644
--- a/osnet/OSXEthernetTap.hpp
+++ b/osnet/OSXEthernetTap.hpp
@@ -68,7 +68,7 @@ public:
 	virtual std::set<InetAddress> ips() const;
 	virtual void put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len);
 	virtual std::string deviceName() const;
-	virtual std::string persistentId() const;
+	virtual void setFriendlyName(const char *friendlyName);
 	virtual bool updateMulticastGroups(std::set<MulticastGroup> &groups);
 
 	void threadMain()
diff --git a/osnet/OSXEthernetTapFactory.cpp b/osnet/OSXEthernetTapFactory.cpp
index 4d0f2069..223cec7f 100644
--- a/osnet/OSXEthernetTapFactory.cpp
+++ b/osnet/OSXEthernetTapFactory.cpp
@@ -100,7 +100,7 @@ EthernetTap *OSXEthernetTapFactory::open(
 	return t;
 }
 
-void OSXEthernetTapFactory::close(EthernetTap *tap)
+void OSXEthernetTapFactory::close(EthernetTap *tap,bool destroyPersistentDevices)
 {
 	{
 		Mutex::Lock _l(_devices_m);
diff --git a/osnet/OSXEthernetTapFactory.hpp b/osnet/OSXEthernetTapFactory.hpp
index 720e038a..2368d982 100644
--- a/osnet/OSXEthernetTapFactory.hpp
+++ b/osnet/OSXEthernetTapFactory.hpp
@@ -62,7 +62,7 @@ public:
 		const char *friendlyName,
 		void (*handler)(void *,const MAC &,const MAC &,unsigned int,const Buffer<4096> &),
 		void *arg);
-	virtual void close(EthernetTap *tap);
+	virtual void close(EthernetTap *tap,bool destroyPersistentDevices);
 	virtual std::vector<std::string> allTapDeviceNames() const;
 
 private: