diff --git a/libwhisper/WhisperHost.cpp b/libwhisper/WhisperHost.cpp
index f9ff33658..4a1f4c8b4 100644
--- a/libwhisper/WhisperHost.cpp
+++ b/libwhisper/WhisperHost.cpp
@@ -68,7 +68,7 @@ void WhisperHost::inject(Envelope const& _m, WhisperPeer* _p)
 		m_expiryQueue.insert(make_pair(_m.expiry(), h));
 	}
 
-	int rating = 1; // rating for local host is based upon: 1. installed watch; 2. proof of work
+	int rating = 1; // rating for local host is based upon: 1. installed watch; 2. ttl; 3. proof of work
 
 	if (_p) // incoming message from remote peer
 		DEV_GUARDED(m_filterLock)
diff --git a/libwhisper/WhisperPeer.cpp b/libwhisper/WhisperPeer.cpp
index 393c3749c..27662926e 100644
--- a/libwhisper/WhisperPeer.cpp
+++ b/libwhisper/WhisperPeer.cpp
@@ -121,17 +121,22 @@ unsigned WhisperPeer::ratingForPeer(Envelope const& e) const
 {
 	// we try to estimate, how valuable this nessage will be for the remote peer,
 	// according to the following criteria:
-	// 1. bloom filter 
-	// 2. proof of work
+	// 1. bloom filter
+	// 2. time to live
+	// 3. proof of work
 
-	static const unsigned BloomFilterMatchReward = 256; // vlad todo: move to common.h
 	unsigned rating = 0;
 
 	DEV_GUARDED(x_bloom)
 		if (e.matchesBloomFilter(m_bloom))
-			rating += BloomFilterMatchReward;
-	
-	rating += e.sha3().firstBitSet();
+			++rating;
+
+	rating *= 256;
+	unsigned ttlReward = (256 > e.ttl() ? 256 - e.ttl() : 0);
+	rating += ttlReward;
+
+	rating *= 256;
+	rating += e.workProved();
 	return rating;
 }
 
diff --git a/test/libwhisper/whisperMessage.cpp b/test/libwhisper/whisperMessage.cpp
index 343573713..1db3352ac 100644
--- a/test/libwhisper/whisperMessage.cpp
+++ b/test/libwhisper/whisperMessage.cpp
@@ -89,4 +89,18 @@ BOOST_AUTO_TEST_CASE(seal)
 		sealAndOpenSingleMessage(i);
 }
 
+BOOST_AUTO_TEST_CASE(work)
+{
+	VerbosityHolder setTemporaryLevel(10);
+	cnote << "Testing proof of work...";
+
+	Secret zero;
+	Topics topics = createRandomTopics(0xDEAD);
+	bytes const payload = createRandomPayload(0xFFFFF);
+	Message m(payload);
+	Envelope e = m.seal(zero, topics, 1, 50);
+	unsigned x = e.workProved();
+	BOOST_REQUIRE(x > 0);
+}
+
 BOOST_AUTO_TEST_SUITE_END()