diff --git a/libretroshare/src/ft/ftchunkmap.cc b/libretroshare/src/ft/ftchunkmap.cc
index cc8dda5c2..d3dcfa849 100644
--- a/libretroshare/src/ft/ftchunkmap.cc
+++ b/libretroshare/src/ft/ftchunkmap.cc
@@ -1,34 +1,251 @@
 #include <math.h>
+#include <assert.h>
+#include <stdlib.h>
 #include "ftchunkmap.h"
 
-ChunkMap::ChunkMap(uint64_t s)
+std::ostream& operator<<(std::ostream& o,const ftChunk& c)
 {
-	file_size = s ;
+	return o << "\tChunk [" << c.offset << "] size: " << c.size << "  ChunkId: " << c.id << "  Age: " << time(NULL) - c.ts ;
+}
 
-	chunk_size = 1024*1024 ;	// 1MB chunks
-	uint64_t n = s/chunk_size ;
-	if(s% (uint64_t)chunk_size != 0)
+// Chunk: very bold implementation for now. We should compress the bits to have
+// 32 of them per uint32_t value, of course!
+//
+Chunk::Chunk(uint64_t start,uint32_t size)
+	: _start(start),_offset(start),_end( (uint64_t)size + start )
+{
+}
+
+void Chunk::getSlice(uint32_t size_hint,ftChunk& chunk)
+{
+	// Take the current offset
+	chunk.offset = _offset ;
+	chunk.size = std::min(size_hint,(uint32_t)(_end-_offset)) ;
+	chunk.id = _offset ;
+	chunk.ts = time(NULL) ;
+	
+	// push the slice marker into currently handled slices.
+	_offset += chunk.size ;
+}
+
+//uint32_t Chunk::dataReceived(const ftChunk::ChunkId cid)
+//{
+//#ifdef DEBUG_FTCHUNK
+//	std::cerr << "*** Chunk::dataReceived: slice " << cid << " finished" << std::endl ;
+//#endif
+//	std::map<ftChunk::ChunkId,uint32_t>::iterator it( _slices_to_download.find(cid) ) ;
+//
+//	if(it == _slices_to_download.end())
+//	{
+//		std::cerr << "!!! Chunk::dataReceived: could not find chunk " << cid << ": probably a fatal error" << std::endl ;
+//		return 0 ;
+//	}
+//	else
+//	{
+//		uint32_t n = it->second ;
+//		_slices_to_download.erase(it) ;
+//		return n ;
+//	}
+//}
+
+ChunkMap::ChunkMap(uint64_t s)
+	:_file_size(s),_chunk_size(1024*1024) 	// 1MB chunks
+{
+	uint64_t n = s/(uint64_t)_chunk_size ;
+	if(s% (uint64_t)_chunk_size != 0)
 		++n ;
 
-	chunks.resize(n,CHUNK_OUTSTANDING) ;
+	_map.resize(n,FileChunksInfo::CHUNK_OUTSTANDING) ;
+	_total_downloaded = 0 ;
+	_strategy = FileChunksInfo::CHUNK_STRATEGY_STREAMING ;
+#ifdef DEBUG_FTCHUNK
+	std::cerr << "*** ChunkMap::ChunkMap: starting new chunkmap:" << std::endl ; 
+	std::cerr << "   File size: " << s << std::endl ;
+	std::cerr << "   Strategy: " << _strategy << std::endl ;
+	std::cerr << "   ChunkSize: " << _chunk_size << std::endl ;
+	std::cerr << "   Number of Chunks: " << n << std::endl ;
+#endif
 }
 
-void ChunkMap::received(uint64_t offset)
+void ChunkMap::dataReceived(const ftChunk::ChunkId& cid)
 {
-	uint64_t n = offset/chunk_size ;
+	// 1 - find which chunk contains the received data.
+	//
 
-	for(uint64_t i=0;i<n;++i)
-		chunks[i] = CHUNK_DONE ;
+	// trick: cid is the chunk offset. So we use it to get the chunk number.
+	int n = (uint64_t)cid/_chunk_size ;
 
-	if(offset == file_size)
-		chunks.back() = CHUNK_DONE ;
+	std::map<ChunkNumber,ChunkDownloadInfo>::iterator itc(_slices_to_download.find(n)) ;
+
+	if(itc == _slices_to_download.end()) 
+	{
+		std::cerr << "!!! ChunkMap::dataReceived: error: ChunkId " << cid << " corresponds to chunk number " << n << ", which is not being downloaded!" << std::endl ;
+		assert(false) ;
+		return ;
+	}
+
+	std::map<ftChunk::ChunkId,uint32_t>::iterator it(itc->second._slices.find(cid)) ;
+
+	if(it == itc->second._slices.end()) 
+	{
+		std::cerr << "!!! ChunkMap::dataReceived: chunk " << cid << " is not found in slice lst of chunk number " << n << std::endl ;
+		assert(false) ;
+		return ;
+	}
+
+	_total_downloaded += it->second ;
+	itc->second._remains -= it->second ;
+	itc->second._slices.erase(it) ;
+
+#ifdef DEBUG_FTCHUNK
+	std::cerr << "*** ChunkMap::dataReceived: received data chunk " << cid << " for chunk number " << n << ", local remains=" << itc->second._remains << ", total downloaded=" << _total_downloaded << ", remains=" << _file_size - _total_downloaded << std::endl ;
+#endif
+	if(itc->second._remains == 0) // the chunk was completely downloaded
+	{
+#ifdef DEBUG_FTCHUNK
+		std::cerr << "*** ChunkMap::dataReceived: Chunk is complete. Removing it." << std::endl ;
+#endif
+		_map[n] = FileChunksInfo::CHUNK_DONE ;
+		_slices_to_download.erase(itc) ;
+	}
 }
 
-void ChunkMap::requested(uint64_t offset, uint32_t size)
+// Warning: a chunk may be empty, but still being downloaded, so asking new slices from it
+// will produce slices of size 0. This happens at the end of each chunk.
+// --> I need to get slices from the next chunk, in such a case.
+// --> solution:
+// 	- have too chunks maps:
+// 		1 indexed by peer id to feed the getChunk method
+// 			- chunks pushed when new chunks are needed
+// 			- chunks removed when empty
+// 		1 indexed by chunk id to account for chunks being downloaded
+// 			- chunks pushed when new chunks are needed
+// 			- chunks removed when completely downloaded
+//
+bool ChunkMap::getDataChunk(const std::string& peer_id,uint32_t size_hint,ftChunk& chunk)
 {
-	int start = offset/chunk_size ;
-	int end = (int)ceil((offset+size)/chunk_size) ;
+#ifdef DEBUG_FTCHUNK
+	std::cerr << "*** ChunkMap::getDataChunk: size_hint = " << size_hint << std::endl ;
+#endif
+	// 1 - find if this peer already has an active chunk.
+	//
+	std::map<std::string,Chunk>::iterator it = _active_chunks_feed.find(peer_id) ;
 
-	for(int i=start;i<=end;++i)
-		chunks[i] = CHUNK_ACTIVE ;
+	if(it == _active_chunks_feed.end())		
+	{
+		// 1 - select an available chunk id for this peer.
+		//
+		uint32_t c ;
+
+		switch(_strategy)
+		{
+			case FileChunksInfo::CHUNK_STRATEGY_STREAMING:	c = getAvailableChunk(0,peer_id) ;	// very bold!!
+																			break ;
+
+			case FileChunksInfo::CHUNK_STRATEGY_RANDOM: 		c = getAvailableChunk(rand()%_map.size(),peer_id) ;
+																			break ;
+			default:
+#ifdef DEBUG_FTCHUNK
+													std::cerr << "!!! ChunkMap::getDataChunk: error!: unknown strategy" << std::endl ;
+#endif
+													return false ;
+		}
+
+		if(c >= _map.size()) 
+			return false ;
+
+		// 2 - add the chunk in the list of active chunks, and mark it as being downloaded
+		//
+		uint32_t soc = sizeOfChunk(c) ;
+		_active_chunks_feed[peer_id] = Chunk( c*(uint64_t)_chunk_size, soc ) ;
+		_map[c] = FileChunksInfo::CHUNK_ACTIVE ;
+		_slices_to_download[c]._remains = soc ;			// init the list of slices to download
+#ifdef DEBUG_FTCHUNK
+		std::cout << "*** ChunkMap::getDataChunk: Allocating new chunk " << c << " for peer " << peer_id << std::endl ;
+#endif
+	}
+#ifdef DEBUG_FTCHUNK
+	else
+		std::cout << "*** ChunkMap::getDataChunk: Re-using chunk " << it->second._start/_chunk_size << " for peer " << peer_id << std::endl ;
+#endif
+
+	// Get the first slice of the chunk, that is at most of length size
+	//
+	_active_chunks_feed[peer_id].getSlice(size_hint,chunk) ;
+	_slices_to_download[chunk.offset/_chunk_size]._slices[chunk.id] = chunk.size ;
+
+	if(_active_chunks_feed[peer_id].empty())
+		_active_chunks_feed.erase(_active_chunks_feed.find(peer_id)) ;
+	
+#ifdef DEBUG_FTCHUNK
+	std::cout << "*** ChunkMap::getDataChunk: returning slice " << chunk << " for peer " << peer_id << std::endl ;
+#endif
+	return true ;
 }
+
+#ifdef A_FAIRE
+void setPeerAvailabilityMap(const std::string& peer_id,const std::vector<uint32_t>& peer_map)
+{
+#ifdef DEBUG_FTCHUNK
+	std::cout << "Receiving new availability map for peer " << peer_id << std::endl ;
+#endif
+
+	_peers_chunks_availability[peer_id] = peer_map ;
+}
+#endif
+
+uint32_t ChunkMap::sizeOfChunk(uint32_t cid) const
+{
+	if(cid == _map.size()-1)
+		return _file_size - (_map.size()-1)*_chunk_size ;
+	else
+		return _chunk_size ;
+}
+
+uint32_t ChunkMap::getAvailableChunk(uint32_t start_location,const std::string& peer_id) const
+{
+	// Very bold algorithm: checks for 1st availabe chunk for this peer starting
+	// from the given start location.
+#ifdef A_FAIRE
+	std::map<std::string,std::vector<uint32_t> >::const_iterator it(_peers_chunks_availability.find(peer_id)) ;
+
+	// Do we have records for this file source ?
+	//
+	if(it == _peers_chunks_availability.end())
+	{
+#ifdef DEBUG_FTCHUNK
+		std::cout << "No chunk map for peer " << peer_id << ": returning false" << endl ;
+#endif
+		return _map.size() ;
+	}
+	const std::vector<uint32_t> peer_chunks(it->second) ;
+#endif
+
+	for(uint i=0;i<_map.size();++i)
+	{
+		uint32_t j = (start_location+i)%_map.size() ;
+
+		if(_map[j] == FileChunksInfo::CHUNK_OUTSTANDING /*&& peers_chunks[j] == CHUNK_DONE*/)
+		{
+#ifdef DEBUG_FTCHUNK
+			std::cerr << "ChunkMap::getAvailableChunk: returning chunk " << j << " for peer " << peer_id << std::endl;
+#endif
+			return j ;
+		}
+	}
+
+#ifdef DEBUG_FTCHUNK
+	std::cout << "!!! ChunkMap::getAvailableChunk: No available chunk from peer " << peer_id << ": returning false" << std::endl ;
+#endif
+	return _map.size() ;
+}
+
+void ChunkMap::getChunksInfo(FileChunksInfo& info) const 
+{
+	info.file_size = _file_size ;
+	info.chunk_size = _chunk_size ;
+	info.chunks = _map ;
+}
+
+
+
diff --git a/libretroshare/src/ft/ftchunkmap.h b/libretroshare/src/ft/ftchunkmap.h
index 6b03ceab6..0732253cd 100644
--- a/libretroshare/src/ft/ftchunkmap.h
+++ b/libretroshare/src/ft/ftchunkmap.h
@@ -1,13 +1,146 @@
 #pragma once
 
+#include <map>
 #include <rsiface/rstypes.h>
 
-class ChunkMap: public FileChunksInfo
+// ftChunkMap: 
+// 	- handles chunk map over a complete file
+// 	- mark down which chunk is being downloaded by which peer
+// 	- allocate data ranges of any requested size for a given peer
+// 		- continuing an existing chunk
+// 		- allocating a new chunk
+//
+// Download mecanism:
+// 	- ftFileCreator handles a list of active slices, and periodically resends requests every 20 sec.
+// 		Slices have arbitrary size (less than a chunk), depending on the transfer rate.
+// 		When receiving data, ftFileCreator shrinks its slices until they get complete. When a slice is finished, it
+// 		notifies ftChunkMap that this slice is done.
+//
+// 	- ftChunkMap maintains two levels:
+// 		- the chunk level (Chunks a 1MB long) with a map of who has which chunk and what locally is the state of 
+// 		each chunk
+// 		- the slice level: each active chunk is cut into slices (basically a list of intervalls) being downloaded, and
+// 		a remaining slice to cut off new candidates. When notified for a complete slice, ftChunkMap removed the
+// 		corresponding acive slice. When asked a slice, ftChunkMap cuts out a slice from the remaining part of the chunk
+// 		to download, sends the slice's coordinates and gives a unique slice id (such as the slice offset).
+
+// This class handles a slice of a chunk, at the level of ftFileCreator
+
+class ftChunk 
 {
 	public:
-		ChunkMap(uint64_t size) ;
+		typedef uint64_t ChunkId ;
 
-		virtual void received(uint64_t offset) ;
-		virtual void requested(uint64_t offset, uint32_t chunk_size) ;
+		ftChunk():offset(0), size(0), ts(0) {}
+
+		friend std::ostream& operator<<(std::ostream& o,const ftChunk& f) ;
+
+		uint64_t offset;
+		uint64_t size;
+		ChunkId  id ;
+		time_t   ts;
 };
 
+// This class handles a single chunk. Although each chunk is requested at once,
+// it may be sent back into sub-chunks because of file transfer rate constraints. 
+// So the dataReceived function should be called to progressively complete the chunk,
+// and the getChunk method should ask for a sub0chunk of a given size.
+//
+class Chunk
+{
+	public: 
+		Chunk(): _start(0),_offset(0),_end(0) {}	// only used in default std::map fillers
+
+		Chunk(uint64_t start,uint32_t size) ;
+
+		void getSlice(uint32_t size_hint,ftChunk& chunk) ;
+
+		// Returns true when the chunk is complete
+		bool empty() const { return _offset == _end ; }
+
+		// Array of intervalls of bytes to download.
+		//
+		uint64_t _start ;		// const
+		uint64_t _offset ;	// not const: handles the current offset within the chunk.
+		uint64_t _end ;		// const
+};
+
+class ChunkDownloadInfo
+{
+	public:
+		std::map<ftChunk::ChunkId,uint32_t> _slices ;
+		uint32_t _remains ;
+};
+
+class ChunkMap
+{
+   public:
+		typedef uint32_t ChunkNumber ;
+
+		// Constructor. Decides what will be the size of chunks and how many there will be.
+
+		ChunkMap(uint64_t file_size) ;
+
+      // Returns an slice of data to be asked to the peer within a chunk.
+		// If a chunk is already been downloaded by this peer, take a slice at
+		// the beginning of this chunk, or at least where it starts.
+		// If not, randomly/streamly select a new chunk depending on the strategy. 
+      // adds an entry in the chunk_ids map, and sets up 1 interval for it.
+      // the chunk should be available from the designated peer. 
+
+      virtual bool getDataChunk(const std::string& peer_id,uint32_t size_hint,ftChunk& chunk) ; 
+
+      // Notify received a slice of data. This needs to 
+      //   - carve in the map of chunks what is received, what is not.
+      //   - tell which chunks are finished. For this, each interval must know what chunk number it has been attributed
+      //    when the interval is split in the middle, the number of intervals for the chunk is increased. If the interval is
+      //    completely covered by the data, the interval number is decreased.
+
+      virtual void dataReceived(const ftChunk::ChunkId& c_id) ;
+
+      // Decides how chunks are selected. 
+      //    STREAMING: the 1st chunk is always returned
+      //       RANDOM: the beginning of a random interval is selected first. If two few intervals 
+      //                exist, the largest one is randomly split into two.
+
+		void setStrategy(FileChunksInfo::ChunkStrategy s) { _strategy = s ; }
+
+#ifdef TO_DO
+      // Properly fills an vector of fixed size chunks with availability or download state.
+      // chunks is given with the proper number of chunks and we have to adapt to it. This can be used
+      // to display square chunks in the gui or display a blue bar of availability by collapsing info from all peers.
+
+      void linearize(FileChunksInfo& info) const ;
+
+		// Updates the peer's availablility map
+		//
+		void setPeerAvailabilityMap(const std::string& peer_id,const std::vector<uint32_t>& peer_map) ;
+#endif
+
+		// Returns the total size of downloaded data in the file.
+		uint64_t getTotalReceived() const { return _total_downloaded ; }
+
+		void getChunksInfo(FileChunksInfo& info) const ;
+	protected:
+		// handles what size the last chunk has.
+		uint32_t sizeOfChunk(uint32_t chunk_number) const ;
+
+		// Returns the first chunk available starting from start_location for this peer_id.
+		//
+		uint32_t getAvailableChunk(uint32_t start_location,const std::string& peer_id) const ;
+
+	private:
+		const uint64_t						_file_size ;		// total size of the file in bytes.
+		const uint32_t						_chunk_size ;		// Size of chunks. Common to all chunks.
+		FileChunksInfo::ChunkStrategy 						_strategy ;			// how do we allocate new chunks
+		std::map<std::string,Chunk>	_active_chunks_feed ; // vector of chunks being downloaded. Exactly one chunk per peer id.
+		std::map<ChunkNumber,ChunkDownloadInfo> _slices_to_download ; // list of (slice id,slice size) 
+
+		std::vector<FileChunksInfo::ChunkState> _map ;				// vector of chunk state over the whole file
+
+		std::map<std::string,std::vector<uint32_t> >	_peers_chunks_availability ;	// what does each source peer have.
+
+		uint64_t								_total_downloaded ;
+};
+
+
diff --git a/libretroshare/src/ft/ftcontroller.cc b/libretroshare/src/ft/ftcontroller.cc
index 32ad7d06f..c136c6ca5 100644
--- a/libretroshare/src/ft/ftcontroller.cc
+++ b/libretroshare/src/ft/ftcontroller.cc
@@ -842,6 +842,21 @@ bool 	ftController::setPeerState(ftTransferModule *tm, std::string id,
 }
 
 
+bool ftController::setChunkStrategy(const std::string& hash,FileChunksInfo::ChunkStrategy s)
+{
+	std::map<std::string,ftFileControl>::iterator mit;
+	mit=mDownloads.find(hash);
+	if (mit==mDownloads.end())
+	{
+#ifdef CONTROL_DEBUG
+		std::cerr<<"ftController::FileCancel file is not found in mDownloads"<<std::endl;
+#endif
+		return false;
+	}
+
+	mit->second.mCreator->setChunkStrategy(s) ;
+	return true ;
+}
 
 bool 	ftController::FileCancel(std::string hash)
 {
diff --git a/libretroshare/src/ft/ftcontroller.h b/libretroshare/src/ft/ftcontroller.h
index 553413a1e..f597bed15 100644
--- a/libretroshare/src/ft/ftcontroller.h
+++ b/libretroshare/src/ft/ftcontroller.h
@@ -132,6 +132,8 @@ bool 	FileRequest(std::string fname, std::string hash,
 			uint64_t size, std::string dest, uint32_t flags,
 			std::list<std::string> &sourceIds);
 
+bool 	setChunkStrategy(const std::string& hash,FileChunksInfo::ChunkStrategy s);
+
 bool 	FileCancel(std::string hash);
 bool 	FileControl(std::string hash, uint32_t flags);
 bool 	FileClearCompleted();
diff --git a/libretroshare/src/ft/ftfilecreator.cc b/libretroshare/src/ft/ftfilecreator.cc
index a03a0b8e9..d7237b715 100644
--- a/libretroshare/src/ft/ftfilecreator.cc
+++ b/libretroshare/src/ft/ftfilecreator.cc
@@ -15,8 +15,8 @@
 *
 ***********************************************************/
 
-ftFileCreator::ftFileCreator(std::string path, uint64_t size, std::string
-hash, uint64_t recvd): ftFileProvider(path,size,hash), chunkMap(size)
+ftFileCreator::ftFileCreator(std::string path, uint64_t size, std::string hash, uint64_t recvd)
+	: ftFileProvider(path,size,hash), chunkMap(size)
 {
 	/* 
          * FIXME any inits to do?
@@ -36,23 +36,25 @@ hash, uint64_t recvd): ftFileProvider(path,size,hash), chunkMap(size)
 	RsStackMutex stack(ftcMutex); /********** STACK LOCKED MTX ******/
 
 	/* initialise the Transfer Lists */
-	mStart = recvd;
-	mEnd = recvd;
+//	mStart = recvd;
+//	mEnd = recvd;
 
-	chunkMap.received(recvd) ;
+#ifdef TO_DO
+	// we should init the chunk map with some bit array saying what is received and what is not!!
+	chunkMap.setTotalReceived(recvd) ;
+#endif
 }
 
-bool    ftFileCreator::getFileData(uint64_t offset, 
-                uint32_t &chunk_size, void *data)
+bool ftFileCreator::getFileData(uint64_t offset, uint32_t &chunk_size, void *data)
 {
 	{
-	  RsStackMutex stack(ftcMutex); /********** STACK LOCKED MTX ******/
-	  if (offset + chunk_size > mStart)
-	  {
-		/* don't have the data */
-		return false;
-	  }
-        }
+		RsStackMutex stack(ftcMutex); /********** STACK LOCKED MTX ******/
+		if (offset + chunk_size > mStart)
+		{
+			/* don't have the data */
+			return false;
+		}
+	}
 
 	return ftFileProvider::getFileData(offset, chunk_size, data);
 }
@@ -60,7 +62,7 @@ bool    ftFileCreator::getFileData(uint64_t offset,
 uint64_t ftFileCreator::getRecvd()
 {
 	RsStackMutex stack(ftcMutex); /********** STACK LOCKED MTX ******/
-	return mStart;
+	return chunkMap.getTotalReceived() ;
 }
 
 bool ftFileCreator::addFileData(uint64_t offset, uint32_t chunk_size, void *data)
@@ -206,8 +208,8 @@ int ftFileCreator::initializeFileAttrs()
         std::cerr << "ftFileCreator::initializeFileAttrs() File Expected Size: " << mSize << " RecvdSize: " << recvdsize << std::endl;
 
 	/* start from there! */
-	mStart = recvdsize;
-	mEnd = recvdsize;
+//	mStart = recvdsize;
+//	mEnd = recvdsize;
 	
 	return 1;
 }
@@ -230,9 +232,9 @@ int ftFileCreator::locked_notifyReceived(uint64_t offset, uint32_t chunk_size)
 #endif
 
 	/* find the chunk */
-	std::map<uint64_t, ftChunk>::iterator it;
-	it = mChunks.find(offset);
-	bool isFirst = false;
+	std::map<uint64_t, ftChunk>::iterator it = mChunks.find(offset);
+
+//	bool isFirst = false;
 	if (it == mChunks.end())
 	{
 #ifdef FILE_DEBUG
@@ -244,35 +246,37 @@ int ftFileCreator::locked_notifyReceived(uint64_t offset, uint32_t chunk_size)
 #endif
 		return 0; /* ignoring */
 	}
-	else if (it == mChunks.begin())
-	{
-		isFirst = true;
-	}
+
+//	if (it == mChunks.begin())
+//	{
+//		isFirst = true;
+//	}
 
 	ftChunk chunk = it->second;
 	mChunks.erase(it);
 
-	if (chunk.chunk != chunk_size)
+	if (chunk.size != chunk_size)
 	{
 		/* partial : shrink chunk */
-		chunk.chunk -= chunk_size;
+		chunk.size -= chunk_size;
 		chunk.offset += chunk_size;
 		mChunks[chunk.offset] = chunk;
 	}
+	else	// notify the chunkmap that the slice is finished
+		chunkMap.dataReceived(chunk.id) ;
 
-	/* update how much has been completed */
-	if (isFirst)
-	{
-		mStart = offset + chunk_size;
-	}
+//	/* update how much has been completed */
+//	if (isFirst)
+//	{
+//		mStart = offset + chunk_size;
+//	}
 
 	// update chunk map
-	chunkMap.received(mStart) ;
 
-	if (mChunks.size() == 0)
-	{
-		mStart = mEnd;
-	}
+//	if (mChunks.size() == 0)
+//	{
+//		mStart = mEnd;
+//	}
 
 	/* otherwise there is another earlier block to go
 	 */
@@ -280,15 +284,25 @@ int ftFileCreator::locked_notifyReceived(uint64_t offset, uint32_t chunk_size)
 	return 1;
 }
 
+void ftFileCreator::setChunkStrategy(FileChunksInfo::ChunkStrategy s)
+{
+	RsStackMutex stack(ftcMutex); /********** STACK LOCKED MTX ******/
+
+#ifdef FILE_DEBUG
+	std::cerr << "ftFileCtreator: setting chunk strategy to " << s << std::endl ;
+#endif
+	chunkMap.setStrategy(s) ;
+}
+
 /* Returns true if more to get 
  * But can return size = 0, if we are still waiting for the data.
  */
 
-bool ftFileCreator::getMissingChunk(uint64_t &offset, uint32_t &chunk) 
+bool ftFileCreator::getMissingChunk(const std::string& peer_id,uint32_t size_hint,uint64_t &offset, uint32_t& size) 
 {
 	RsStackMutex stack(ftcMutex); /********** STACK LOCKED MTX ******/
 #ifdef FILE_DEBUG
-	std::cerr << "ffc::getMissingChunk(...,"<< chunk << ")";
+	std::cerr << "ffc::getMissingChunk(...,"<< size_hint << ")";
 	std::cerr << " this: " << this;
 	std::cerr << std::endl;
 	locked_printChunkMap();
@@ -296,14 +310,14 @@ bool ftFileCreator::getMissingChunk(uint64_t &offset, uint32_t &chunk)
 
 	/* check start point */
 
-	if (mStart == mSize)
-	{
-#ifdef FILE_DEBUG
-		std::cerr << "ffc::getMissingChunk() File Done";
-		std::cerr << std::endl;
-#endif
-		return false;
-	}
+//	if(mStart == mSize)
+//	{
+//#ifdef FILE_DEBUG
+//		std::cerr << "ffc::getMissingChunk() File Done";
+//		std::cerr << std::endl;
+//#endif
+//		return false;
+//	}
 
 	/* check for freed chunks */
 	time_t ts = time(NULL);
@@ -316,48 +330,47 @@ bool ftFileCreator::getMissingChunk(uint64_t &offset, uint32_t &chunk)
 		if (it->second.ts < old)
 		{
 #ifdef FILE_DEBUG
-			std::cerr << "ffc::getMissingChunk() ReAlloc";
+			std::cerr << "ffc::getMissingChunk() Re-asking for an old chunk";
 			std::cerr << std::endl;
 #endif
 
 			/* retry this one */
 			it->second.ts = ts;
-			chunk = it->second.chunk;
+			size = it->second.size;
 			offset = it->second.offset;
 
 			return true;
 		}
 	}
 
-#ifdef FILE_DEBUG
-	std::cerr << "ffc::getMissingChunk() new Alloc";
-	std::cerr << "  mStart: " << mStart << " mEnd: " << mEnd;
-	std::cerr << "mSize: " << mSize;
-	std::cerr << std::endl;
-#endif
-
 	/* else allocate a new chunk */
-	if (mSize - mEnd < chunk)
-		chunk = mSize - mEnd;
 
-	offset = mEnd;
-	mEnd += chunk;
+	ftChunk chunk ;
 
-	if (chunk > 0)
-	{
+	if(!chunkMap.getDataChunk(peer_id,size_hint,chunk))
+		return false ;
+
+//	if (mSize - mEnd < chunk)
+//		chunk = mSize - mEnd;
+//
+//	offset = mEnd;
+//	mEnd += chunk;
+
+//	if (chunk > 0)
+//	{
 #ifdef FILE_DEBUG
-		std::cerr << "ffc::getMissingChunk() Allocated " << chunk;
-		std::cerr << " offset: " << offset;
-		std::cerr << std::endl;
-		std::cerr << "  mStart: " << mStart << " mEnd: " << mEnd;
-		std::cerr << "mSize: " << mSize;
-		std::cerr << std::endl;
+	std::cerr << "ffc::getMissingChunk() Retrieved new chunk: " << chunk << std::endl ;
+//		std::cerr << std::endl;
+//		std::cerr << "  mStart: " << mStart << " mEnd: " << mEnd;
+//		std::cerr << "mSize: " << mSize;
+//		std::cerr << std::endl;
 #endif
 
-		mChunks[offset] = ftChunk(offset, chunk, ts);
+	mChunks[chunk.offset] = chunk ;
 
-		chunkMap.requested(offset,chunk) ;
-	}
+	offset = chunk.offset ;
+	size = chunk.size ;
+//	}
 
 	return true; /* cos more data to get */
 }
@@ -365,7 +378,8 @@ bool ftFileCreator::getMissingChunk(uint64_t &offset, uint32_t &chunk)
 void ftFileCreator::getChunkMap(FileChunksInfo& info)
 {
 	RsStackMutex stack(ftcMutex); /********** STACK LOCKED MTX ******/
-	info = chunkMap ;
+
+	chunkMap.getChunksInfo(info) ;
 }
 
 bool ftFileCreator::locked_printChunkMap()
@@ -377,37 +391,16 @@ bool ftFileCreator::locked_printChunkMap()
 #endif
 
 	/* check start point */
-	std::cerr << "Size: " << mSize << " Start: " << mStart << " End: " << mEnd;
-	std::cerr << std::endl;
-	std::cerr << "\tOutstanding Chunks (in the middle)";
+//	std::cerr << "Size: " << mSize << " Start: " << mStart << " End: " << mEnd;
+	std::cerr << "\tOutstanding Chunks:";
 	std::cerr << std::endl;
 
 	std::map<uint64_t, ftChunk>::iterator it;
-	time_t ts = time(NULL);
+	
 	for(it = mChunks.begin(); it != mChunks.end(); it++)
-	{
-		std::cerr << "\tChunk [" << it->second.offset << "] size: ";
-		std::cerr << it->second.chunk;
-		std::cerr << "  Age: " << ts - it->second.ts;
-		std::cerr << std::endl;
-	}
+		std::cerr << "  " << it->second << std::endl ;
+
 	return true; 
 }
 
-/***********************************************************
-*
-*	ftChunk methods
-*
-***********************************************************/
-
-ftChunk::ftChunk(uint64_t ioffset,uint64_t size,time_t now) 
-   : offset(ioffset), chunk(size), ts(now)
-{
-
-}
-
-ftChunk::~ftChunk()
-{
-
-}
 
diff --git a/libretroshare/src/ft/ftfilecreator.h b/libretroshare/src/ft/ftfilecreator.h
index 2b990172a..91b14c19b 100644
--- a/libretroshare/src/ft/ftfilecreator.h
+++ b/libretroshare/src/ft/ftfilecreator.h
@@ -35,7 +35,6 @@
 #include "ftfileprovider.h"
 #include "ftchunkmap.h"
 #include <map>
-class ftChunk;
 
 class ftFileCreator: public ftFileProvider
 {
@@ -51,12 +50,13 @@ virtual bool 	getFileData(uint64_t offset, uint32_t &chunk_size, void *data);
 	uint64_t getRecvd();
 		
 	void getChunkMap(FileChunksInfo& info) ;
+	void setChunkStrategy(FileChunksInfo::ChunkStrategy s) ;
 
 	/* 
 	 * creation functions for FileCreator 
          */
 
-	bool	getMissingChunk(uint64_t &offset, uint32_t &chunk);
+	bool	getMissingChunk(const std::string& peer_id,uint32_t size_hint,uint64_t& offset, uint32_t& size);
 	bool 	addFileData(uint64_t offset, uint32_t chunk_size, void *data);
 
 protected:
@@ -79,15 +79,4 @@ private:
 	ChunkMap chunkMap ;
 };
 
-class ftChunk {
-public:
-	ftChunk(uint64_t,uint64_t,time_t);
-	ftChunk():offset(0), chunk(0), ts(0) {}
-	~ftChunk();
-
-	uint64_t offset;
-	uint64_t chunk;
-	time_t   ts;
-};
-
 #endif // FT_FILE_CREATOR_HEADER
diff --git a/libretroshare/src/ft/ftserver.cc b/libretroshare/src/ft/ftserver.cc
index c46a0f709..579fce9a0 100644
--- a/libretroshare/src/ft/ftserver.cc
+++ b/libretroshare/src/ft/ftserver.cc
@@ -256,6 +256,11 @@ bool ftServer::FileRequest(std::string fname, std::string hash, uint64_t size,
 	return true ;
 }
 
+bool ftServer::setChunkStrategy(const std::string& hash,FileChunksInfo::ChunkStrategy s)
+{
+	return mFtController->setChunkStrategy(hash,s);
+}
+
 bool ftServer::FileCancel(std::string hash)
 {
 	rsTurtle->stopMonitoringFileTunnels(hash) ;
diff --git a/libretroshare/src/ft/ftserver.h b/libretroshare/src/ft/ftserver.h
index 68f9c5885..50380b502 100644
--- a/libretroshare/src/ft/ftserver.h
+++ b/libretroshare/src/ft/ftserver.h
@@ -121,6 +121,7 @@ virtual bool FileRequest(std::string fname, std::string hash, uint64_t size,
 virtual bool FileCancel(std::string hash);
 virtual bool FileControl(std::string hash, uint32_t flags);
 virtual bool FileClearCompleted();
+virtual bool setChunkStrategy(const std::string& hash,FileChunksInfo::ChunkStrategy s) ;
 
 /***
  * Control of Downloads Priority.
diff --git a/libretroshare/src/ft/fttransfermodule.cc b/libretroshare/src/ft/fttransfermodule.cc
index 00b53b09b..43cfe107b 100644
--- a/libretroshare/src/ft/fttransfermodule.cc
+++ b/libretroshare/src/ft/fttransfermodule.cc
@@ -261,8 +261,7 @@ uint32_t ftTransferModule::getDataRate(std::string peerId)
 
 
   //interface to client module
-bool ftTransferModule::recvFileData(std::string peerId, uint64_t offset, 
-			uint32_t chunk_size, void *data)
+bool ftTransferModule::recvFileData(std::string peerId, uint64_t offset, uint32_t chunk_size, void *data)
 {
 #ifdef FT_DEBUG
 	std::cerr << "ftTransferModule::recvFileData()";
@@ -316,18 +315,19 @@ void ftTransferModule::requestData(std::string peerId, uint64_t offset, uint32_t
   mMultiplexor->sendDataRequest(peerId, mHash, mSize, offset,chunk_size);
 }
 
-bool ftTransferModule::getChunk(uint64_t &offset, uint32_t &chunk_size)
+bool ftTransferModule::getChunk(const std::string& peer_id,uint32_t size_hint,uint64_t &offset, uint32_t &chunk_size)
 {
 #ifdef FT_DEBUG
 	std::cerr << "ftTransferModule::getChunk()";
 	std::cerr << " hash: " << mHash;
 	std::cerr << " size: " << mSize;
 	std::cerr << " offset: " << offset;
+	std::cerr << " size_hint: " << size_hint;
 	std::cerr << " chunk_size: " << chunk_size;
 	std::cerr << std::endl;
 #endif
 
-  	bool val = mFileCreator->getMissingChunk(offset, chunk_size);
+  	bool val = mFileCreator->getMissingChunk(peer_id,size_hint,offset, chunk_size);
 
 #ifdef FT_DEBUG
 	if (val)
@@ -595,7 +595,9 @@ bool ftTransferModule::locked_tickPeerTransfer(peerInfo &info)
 		info.state = PQIPEER_IDLE;
 		return false;
 	}
-
+#ifdef FT_DEBUG
+	std::cerr << "locked_tickPeerTransfer() actual rate (before): " << info.actualRate << ", lastTransfers=" << info.lastTransfers << std::endl ;
+#endif
 	/* update rate */
 	info.actualRate = info.actualRate * 0.75 + 0.25 * info.lastTransfers;
 	info.lastTransfers = 0;
@@ -617,15 +619,23 @@ bool ftTransferModule::locked_tickPeerTransfer(peerInfo &info)
 	{
 		if (info.mRateIncrease > 0)
 		{
+#ifdef FT_DEBUG
+			std::cerr << "!!! - Emergency shutdown because rttActive is true, and age is " << ts - info.rttStart << std::endl ;
+#endif
 			info.mRateIncrease = 0;
+			info.rttActive = false ; // I've added this to avoid being stuck when rttActive is true
 		}
 	}
 
 	/* request at more than current rate */
 	uint32_t next_req = info.actualRate * (1.0 + info.mRateIncrease);
 #ifdef FT_DEBUG
+	std::cerr << "locked_tickPeerTransfer() actual rate (after): " << actualRate 
+				<< " increase factor=" << 1.0 + info.mRateIncrease 
+				<< " info.desiredRate=" << info.desiredRate 
+				<< " info.actualRate=" << info.actualRate 
+				<< ", next_req=" << next_req ;
 
-	std::cerr << "locked_tickPeerTransfer() actual rate: " << actualRate;
 	std::cerr << std::endl;
 #endif
 
@@ -667,19 +677,21 @@ bool ftTransferModule::locked_tickPeerTransfer(peerInfo &info)
 	
 	/* do request */
 	uint64_t req_offset = 0;
-	if (getChunk(req_offset,next_req))
+	uint32_t req_size =0 ;
+
+	if (getChunk(info.peerId,next_req,req_offset,req_size))
 	{
-		if (next_req > 0)
+		if (req_size > 0)
 		{
 			info.state = PQIPEER_DOWNLOADING;
-			requestData(info.peerId,req_offset,next_req);
+			requestData(info.peerId,req_offset,req_size);
 
 			/* start next rtt measurement */
 			if (!info.rttActive)
 			{
 				info.rttStart = ts;
 				info.rttActive = true;
-				info.rttOffset = req_offset + next_req;
+				info.rttOffset = req_offset + req_size;
 			}
 		}
 		else
@@ -688,9 +700,8 @@ bool ftTransferModule::locked_tickPeerTransfer(peerInfo &info)
 			std::cerr << std::endl;
 		}
 	}
-	else mFlag = 1;      
-
-	return true ;
+	else 
+		mFlag = 1;      
 
 	return true;
 }
@@ -704,6 +715,8 @@ bool ftTransferModule::locked_recvPeerData(peerInfo &info, uint64_t offset,
 #ifdef FT_DEBUG
 	std::cerr << "ftTransferModule::locked_recvPeerData()";
 	std::cerr << " peerId: " << info.peerId;
+	std::cerr << " rttOffset: " << info.rttOffset;
+	std::cerr << " lastTransfers: " << info.lastTransfers;
 	std::cerr << " offset: " << offset;
 	std::cerr << " chunksize: " << chunk_size;
 	std::cerr << " data: " << data;
@@ -718,36 +731,36 @@ bool ftTransferModule::locked_recvPeerData(peerInfo &info, uint64_t offset,
 
   if ((info.rttActive) && (info.rttOffset == offset + chunk_size))
   {
-  	/* update tip */
-	int32_t rtt = time(NULL) - info.rttStart;
+	  /* update tip */
+	  int32_t rtt = time(NULL) - info.rttStart;
 
-	/* 
-	 * FT_TM_FAST_RTT = 1 sec. mRateIncrease =  1.00
-	 * FT_TM_SLOW_RTT = 9 sec. mRateIncrease =  0
-	 * 		   11 sec. mRateIncrease = -0.25
-	 * if it is slower than this allow fast data increase.
-	 * initial guess - linear with rtt.
-	 * change if this leads to wild oscillations 
-	 *
-	 */
+	  /* 
+		* FT_TM_FAST_RTT = 1 sec. mRateIncrease =  1.00
+		* FT_TM_SLOW_RTT = 9 sec. mRateIncrease =  0
+		* 		   11 sec. mRateIncrease = -0.25
+		* if it is slower than this allow fast data increase.
+		* initial guess - linear with rtt.
+		* change if this leads to wild oscillations 
+		*
+		*/
 
-	info.mRateIncrease = (FT_TM_SLOW_RTT - rtt) * 
-		(FT_TM_MAX_INCREASE / (FT_TM_SLOW_RTT - FT_TM_FAST_RTT));
+	  info.mRateIncrease = (FT_TM_SLOW_RTT - rtt) * 
+		  (FT_TM_MAX_INCREASE / (FT_TM_SLOW_RTT - FT_TM_FAST_RTT));
 
-	if (info.mRateIncrease > FT_TM_MAX_INCREASE)
-		info.mRateIncrease = FT_TM_MAX_INCREASE;
+	  if (info.mRateIncrease > FT_TM_MAX_INCREASE)
+		  info.mRateIncrease = FT_TM_MAX_INCREASE;
 
-	if (info.mRateIncrease < FT_TM_MIN_INCREASE)
-		info.mRateIncrease = FT_TM_MIN_INCREASE;
+	  if (info.mRateIncrease < FT_TM_MIN_INCREASE)
+		  info.mRateIncrease = FT_TM_MIN_INCREASE;
 
-	info.rtt = rtt;
-	info.rttActive = false;
+	  info.rtt = rtt;
+	  info.rttActive = false;
 
 #ifdef FT_DEBUG
-	std::cerr << "ftTransferModule::locked_recvPeerData()";
-	std::cerr << "Updated Rate based on RTT: " << rtt;
-	std::cerr << " Rate: " << info.mRateIncrease;
-	std::cerr << std::endl;
+	  std::cerr << "ftTransferModule::locked_recvPeerData()";
+	  std::cerr << "Updated Rate based on RTT: " << rtt;
+	  std::cerr << " Rate: " << info.mRateIncrease;
+	  std::cerr << std::endl;
 #endif
 
   }
diff --git a/libretroshare/src/ft/fttransfermodule.h b/libretroshare/src/ft/fttransfermodule.h
index a75b68b11..3d6015308 100644
--- a/libretroshare/src/ft/fttransfermodule.h
+++ b/libretroshare/src/ft/fttransfermodule.h
@@ -55,7 +55,8 @@ class peerInfo
 {
 public:
 	peerInfo(std::string peerId_in):peerId(peerId_in),state(PQIPEER_NOT_ONLINE),desiredRate(0),actualRate(0),
-		offset(0),chunkSize(0),receivedSize(0),lastTS(0),
+//		offset(0),chunkSize(0),receivedSize(0),
+		lastTS(0),
 		recvTS(0), lastTransfers(0), nResets(0), 
 		rtt(0), rttActive(false), rttStart(0), rttOffset(0),
 		mRateIncrease(1)
@@ -64,7 +65,8 @@ public:
 	}
 	peerInfo(std::string peerId_in,uint32_t state_in,uint32_t maxRate_in):
 		peerId(peerId_in),state(state_in),desiredRate(maxRate_in),actualRate(0),
-		offset(0),chunkSize(0),receivedSize(0),lastTS(0),
+//		offset(0),chunkSize(0),receivedSize(0),
+		lastTS(0),
 		recvTS(0), lastTransfers(0), nResets(0), 
 		rtt(0), rttActive(false), rttStart(0), rttOffset(0),
 		mRateIncrease(1)
@@ -77,11 +79,11 @@ public:
   	double actualRate;
 
   	//current file data request
-  	uint64_t offset;
-  	uint32_t chunkSize;
+//  	uint64_t offset;
+//  	uint32_t chunkSize;
 
   	//already received data size for current request
-  	uint32_t receivedSize;
+//  	uint32_t receivedSize;
 
   	time_t lastTS; /* last Request */
 	time_t recvTS; /* last Recv */
@@ -147,7 +149,7 @@ public:
   void requestData(std::string peerId, uint64_t offset, uint32_t chunk_size);
 
   //interface to file creator
-  bool getChunk(uint64_t &offset, uint32_t &chunk_size);
+  bool getChunk(const std::string& peer_id,uint32_t size_hint,uint64_t &offset, uint32_t &chunk_size);
   bool storeData(uint64_t offset, uint32_t chunk_size, void *data);
 
   int tick();
diff --git a/libretroshare/src/rsiface/rsfiles.h b/libretroshare/src/rsiface/rsfiles.h
index 28d0aedbe..5943d6846 100644
--- a/libretroshare/src/rsiface/rsfiles.h
+++ b/libretroshare/src/rsiface/rsfiles.h
@@ -110,6 +110,7 @@ virtual ~RsFiles() { return; }
 virtual bool FileRequest(std::string fname, std::string hash, uint64_t size,
 		std::string dest, uint32_t flags, std::list<std::string> srcIds) = 0;
 virtual bool FileCancel(std::string hash) = 0;
+virtual bool setChunkStrategy(const std::string& hash,FileChunksInfo::ChunkStrategy) = 0;
 virtual bool FileControl(std::string hash, uint32_t flags) = 0;
 virtual bool FileClearCompleted() = 0;
 
diff --git a/libretroshare/src/rsiface/rstypes.h b/libretroshare/src/rsiface/rstypes.h
index 9b8afae01..466e5ea7f 100644
--- a/libretroshare/src/rsiface/rstypes.h
+++ b/libretroshare/src/rsiface/rstypes.h
@@ -252,6 +252,7 @@ class FileChunksInfo
 {
 	public:
 	enum ChunkState { CHUNK_DONE, CHUNK_ACTIVE, CHUNK_OUTSTANDING } ;
+	enum ChunkStrategy { CHUNK_STRATEGY_STREAMING, CHUNK_STRATEGY_RANDOM } ;
 
 	uint64_t file_size ;					// real size of the file
 	uint32_t chunk_size ;				// size of chunks
diff --git a/retroshare-gui/src/gui/TransfersDialog.cpp b/retroshare-gui/src/gui/TransfersDialog.cpp
index 8a170b136..f548ff01d 100644
--- a/retroshare-gui/src/gui/TransfersDialog.cpp
+++ b/retroshare-gui/src/gui/TransfersDialog.cpp
@@ -303,6 +303,16 @@ void TransfersDialog::downloadListCostumPopupMenu( QPoint point )
 	  priorityMenu->addAction(priorityHighAct);
 	  priorityMenu->addAction(priorityAutoAct);
 
+	  chunkStreamingAct = new QAction(QIcon(IMAGE_PRIORITYAUTO), tr("Streaming"), this);
+	  connect(chunkStreamingAct, SIGNAL(triggered()), this, SLOT(chunkStreaming()));
+	  chunkRandomAct = new QAction(QIcon(IMAGE_PRIORITYAUTO), tr("Random"), this);
+	  connect(chunkRandomAct, SIGNAL(triggered()), this, SLOT(chunkRandom()));
+
+	  QMenu *chunkMenu = new QMenu(tr("Chunk strategy"), this);
+	  chunkMenu->setIcon(QIcon(IMAGE_PRIORITY));
+	  chunkMenu->addAction(chunkStreamingAct);
+	  chunkMenu->addAction(chunkRandomAct);
+
       contextMnu.clear();
       if (addPlayOption)
       {
@@ -310,6 +320,7 @@ void TransfersDialog::downloadListCostumPopupMenu( QPoint point )
       }
       contextMnu.addSeparator();
       contextMnu.addMenu( priorityMenu);
+      contextMnu.addMenu( chunkMenu);
       contextMnu.addAction( pauseAct);
       contextMnu.addAction( resumeAct);
       contextMnu.addAction( cancelAct);
@@ -1252,6 +1263,25 @@ void TransfersDialog::clearQueue()
 	rsFiles->clearQueue();
 }
 
+void TransfersDialog::chunkStreaming()
+{
+	setChunkStrategy(FileChunksInfo::CHUNK_STRATEGY_STREAMING) ;
+}
+void TransfersDialog::chunkRandom()
+{
+	setChunkStrategy(FileChunksInfo::CHUNK_STRATEGY_RANDOM) ;
+}
+void TransfersDialog::setChunkStrategy(FileChunksInfo::ChunkStrategy s)
+{
+	QList<QStandardItem *> items;
+	QList<QStandardItem *>::iterator it;
+	getIdOfSelectedItems(items);
+
+	for (it = items.begin(); it != items.end(); it ++) {
+		std::string hash = (*it)->data(Qt::DisplayRole).toString().toStdString();
+		rsFiles->setChunkStrategy(hash, s);
+	}
+}
 /* modify download priority actions */
 void TransfersDialog::priorityLow()
 {
diff --git a/retroshare-gui/src/gui/TransfersDialog.h b/retroshare-gui/src/gui/TransfersDialog.h
index dd0aa3315..e71488793 100644
--- a/retroshare-gui/src/gui/TransfersDialog.h
+++ b/retroshare-gui/src/gui/TransfersDialog.h
@@ -30,6 +30,7 @@
 #include <QVariant>
 #include <stdint.h>
 
+#include <rsiface/rstypes.h>
 #include "mainpage.h"
 #include "RsAutoUpdatePage.h"
 
@@ -90,6 +91,9 @@ class TransfersDialog : public RsAutoUpdatePage
 	void priorityHigh();
 	void priorityAuto();
 
+	void chunkRandom();
+	void chunkStreaming();
+
 	/** save sort indicators for next transfers display */
 	void saveSortIndicatorDwl(int logicalIndex, Qt::SortOrder order);
 	void saveSortIndicatorUpl(int logicalIndex, Qt::SortOrder order);
@@ -143,10 +147,13 @@ class TransfersDialog : public RsAutoUpdatePage
 		QAction *priorityNormalAct;
 		QAction *priorityHighAct;
 		QAction *priorityAutoAct;
+		QAction *chunkRandomAct;
+		QAction *chunkStreamingAct;
 
 	void getIdOfSelectedItems(QList<QStandardItem *>& items);
     bool controlTransferFile(uint32_t flags);
     void changePriority(int priority);
+	void setChunkStrategy(FileChunksInfo::ChunkStrategy s) ;
 
 		QTreeView *downloadList;
 
diff --git a/retroshare-gui/src/rsiface/rsfiles.h b/retroshare-gui/src/rsiface/rsfiles.h
index 28d0aedbe..5943d6846 100644
--- a/retroshare-gui/src/rsiface/rsfiles.h
+++ b/retroshare-gui/src/rsiface/rsfiles.h
@@ -110,6 +110,7 @@ virtual ~RsFiles() { return; }
 virtual bool FileRequest(std::string fname, std::string hash, uint64_t size,
 		std::string dest, uint32_t flags, std::list<std::string> srcIds) = 0;
 virtual bool FileCancel(std::string hash) = 0;
+virtual bool setChunkStrategy(const std::string& hash,FileChunksInfo::ChunkStrategy) = 0;
 virtual bool FileControl(std::string hash, uint32_t flags) = 0;
 virtual bool FileClearCompleted() = 0;
 
diff --git a/retroshare-gui/src/rsiface/rstypes.h b/retroshare-gui/src/rsiface/rstypes.h
index 9b8afae01..466e5ea7f 100644
--- a/retroshare-gui/src/rsiface/rstypes.h
+++ b/retroshare-gui/src/rsiface/rstypes.h
@@ -252,6 +252,7 @@ class FileChunksInfo
 {
 	public:
 	enum ChunkState { CHUNK_DONE, CHUNK_ACTIVE, CHUNK_OUTSTANDING } ;
+	enum ChunkStrategy { CHUNK_STRATEGY_STREAMING, CHUNK_STRATEGY_RANDOM } ;
 
 	uint64_t file_size ;					// real size of the file
 	uint32_t chunk_size ;				// size of chunks