diff --git a/2nodetest.sh b/2nodetest.sh
new file mode 100755
index 0000000000..2f3e49e4c5
--- /dev/null
+++ b/2nodetest.sh
@@ -0,0 +1,26 @@
+#!/bin/sh
+
+Datadir0="~/.mainnode"
+Datadir1="~/.peernode"
+
+#build/bin/geth --datadir $Datadir0 removedb
+#build/bin/geth --datadir $Datadir1 removedb
+
+rm -rf ~/.ethash
+rm -rf $Datadir0
+rm -rf $Datadir1
+
+echo "node datadir cleared"
+
+echo "main node init"
+build/bin/geth --datadir $Datadir0 init genesis.json
+build/bin/geth --datadir $Datadir0 --port 30303 --networkid 9876 --exec 'loadScript("yapen/mainnode.js")' console &
+
+sleep 4s
+
+echo "peer node init"
+build/bin/geth --datadir $Datadir1 init genesis.json
+build/bin/geth --datadir $Datadir1 --port 30304 --networkid 9876 --exec 'loadScript("yapen/peernode.js")' console
+
+echo "all command executed"
+
diff --git a/consensus/ethash/consensus.go b/consensus/ethash/consensus.go
index 99eec82211..dab04e88af 100644
--- a/consensus/ethash/consensus.go
+++ b/consensus/ethash/consensus.go
@@ -287,8 +287,10 @@ func (ethash *Ethash) verifyHeader(chain consensus.ChainReader, header, parent *
 // CalcDifficulty is the difficulty adjustment algorithm. It returns
 // the difficulty that a new block should have when created at time
 // given the parent block's time and difficulty.
+// TODO Wei: update the difficulty calculation function to reduce the rate of blck difficulty increment
 func (ethash *Ethash) CalcDifficulty(chain consensus.ChainReader, time uint64, parent *types.Header) *big.Int {
-	return CalcDifficulty(chain.Config(), time, parent)
+	//return CalcDifficulty(chain.Config(), time, parent)
+	return big.NewInt(0x200)
 }
 
 // CalcDifficulty is the difficulty adjustment algorithm. It returns
diff --git a/count_eth.sh b/count_eth.sh
new file mode 100644
index 0000000000..712687c203
--- /dev/null
+++ b/count_eth.sh
@@ -0,0 +1,10 @@
+#!/bin/sh
+dirlist=$(find -mindepth 1 -maxdepth 1 -type d)
+
+for dir in $dirlist
+do
+  cd $dir
+  echo $dir
+  grep -i eth -r | wc -l  
+  cd ..
+done
\ No newline at end of file
diff --git a/current_count.tsv b/current_count.tsv
new file mode 100644
index 0000000000..a1012a2c63
--- /dev/null
+++ b/current_count.tsv
@@ -0,0 +1,74 @@
+./.git
+13
+./.github
+6
+./accounts
+865
+./bmt
+20
+./build
+136
+./cmd
+1599
+./common
+194
+./consensus
+368
+./console
+100
+./containers
+20
+./contracts
+312
+./core
+1290
+./crypto
+158
+./dashboard
+275
+./eth
+1194
+./ethclient
+88
+./ethdb
+36
+./ethstats
+55
+./event
+73
+./internal
+919
+./les
+560
+./light
+246
+./log
+45
+./metrics
+31
+./miner
+109
+./mobile
+329
+./node
+163
+./p2p
+657
+./params
+85
+./rlp
+66
+./rpc
+337
+./signer
+235
+./swarm
+616
+./tests
+154
+./trie
+206
+./vendor
+5513
+./whisper
+300
diff --git a/genesis.json b/genesis.json
new file mode 100644
index 0000000000..115304818c
--- /dev/null
+++ b/genesis.json
@@ -0,0 +1,11 @@
+{
+    "config": {
+        "chainId": 987,
+        "homesteadBlock": 0,
+        "eip155Block": 0,
+        "eip158Block": 0
+    },
+    "difficulty": "0x200",
+    "gasLimit": "0x8000000",
+    "alloc": {}
+}
diff --git a/node0.js b/node0.js
new file mode 100644
index 0000000000..b256e08f39
--- /dev/null
+++ b/node0.js
@@ -0,0 +1,47 @@
+function sleep(milliseconds) {
+  var start = new Date().getTime();
+  for (var i = 0; i < 1e7; i++) {
+    if ((new Date().getTime() - start) > milliseconds){
+      break;
+    }
+  }
+}
+
+function interaction() {
+   personal.newAccount("123456")
+   personal.newAccount("123456")
+   acc0 = web3.eth.accounts[0]
+   acc1 = web3.eth.accounts[1]
+   console.log("account list: " + eth.accounts)
+   console.log("acc0 balance: " + web3.fromWei(web3.eth.getBalance(acc0)))
+   console.log("acc1 balance: " + web3.fromWei(web3.eth.getBalance(acc1)))
+
+   miner.setEtherbase(eth.accounts[0])
+   miner.start()
+
+   while (1) {
+     balance = web3.fromWei(web3.eth.getBalance(acc0)) 
+     if (balance > 0) {
+        miner.stop()
+        personal.unlockAccount(acc0, "123456")
+        eth.sendTransaction({from:acc0,to:acc1,value:web3.toWei(1,"ether")})
+        miner.start()
+       // sleep(10000)
+         //  if (balance1 = balance - 1) {
+	       while (1) {
+	  	  balance1 = web3.fromWei(web3.eth.getBalance(acc1))
+		  if (balance1 > 0) {
+		     miner.stop()
+                      break
+		  }
+               }  
+               console.log("acc0 balance: " + web3.fromWei(web3.eth.getBalance(acc0)))
+               console.log("acc1 balance: " + web3.fromWei(web3.eth.getBalance(acc1)))
+	 //  }
+        break 
+     }
+  }
+  console.log(admin.nodeInfo.id)
+}
+
+interaction()
diff --git a/node0.sh b/node0.sh
new file mode 100644
index 0000000000..0bcfe99db0
--- /dev/null
+++ b/node0.sh
@@ -0,0 +1,7 @@
+rm -rf /home/vivid/.ethereum/*
+echo "main node datadir cleared"
+./geth --datadir /home/vivid/.ethereum init genesis.json
+
+sleep 1s
+./geth --datadir /home/vivid/.ethereum --port 30303 --networkid 9876 console
+
diff --git a/node1.js b/node1.js
new file mode 100644
index 0000000000..34cf440edc
--- /dev/null
+++ b/node1.js
@@ -0,0 +1,19 @@
+function sleep(milliseconds) {
+  var start = new Date().getTime();
+  for (var i = 0; i < 1e7; i++) {
+    if ((new Date().getTime() - start) > milliseconds){
+      break;
+    }
+  }
+}
+
+function interaction() {
+        console.log("peer count: " + net.peerCount)
+	admin.addPeer("enode://a321db2296eb0078fab331d27460456f9c66c478049ee34441595d9c4fc4391af31f24b81fcdf21f28a7e391d07ab4fc550b6e235021abad310992f32d2fc876@127.0.0.1:30303")
+	sleep(5000)	
+        console.log("peer count: " + net.peerCount)
+
+
+}
+
+interaction()
diff --git a/node1.sh b/node1.sh
new file mode 100644
index 0000000000..049d48d747
--- /dev/null
+++ b/node1.sh
@@ -0,0 +1,7 @@
+rm -rf /home/vivid/peernode/*
+echo "peer node datadir cleared"
+./geth --datadir /home/vivid/peernode init genesis.json
+
+sleep 1s
+./geth --datadir /home/vivid/peernode --port 30304 --networkid 9876 console
+
diff --git a/yapen/mainnode.js b/yapen/mainnode.js
new file mode 100644
index 0000000000..ebaa082605
--- /dev/null
+++ b/yapen/mainnode.js
@@ -0,0 +1,40 @@
+function sleep(milliseconds) {
+  var start = new Date().getTime();
+  for (var i = 0; i < 1e7; i++) {
+    if ((new Date().getTime() - start) > milliseconds){
+      break;
+    }
+  }
+}
+
+function interaction() {
+    personal.newAccount("123456")
+    acc0 = web3.eth.accounts[0]
+    acc1 = web3.eth.accounts[1]
+    console.log("[mainnode]: account list: " + eth.accounts)
+    console.log("[mainnode]: acc0 balance: " + web3.fromWei(web3.eth.getBalance(acc0)))
+    console.log("[mainnode]: acc1 balance: " + web3.fromWei(web3.eth.getBalance(acc1)))
+
+    miner.setEtherbase(eth.accounts[0])
+    miner.start()
+
+    personal.unlockAccount(acc0, "123456")
+    eth.sendTransaction({from:acc0,to:acc1,value:web3.toWei(1,"ether")})
+    while (1) {
+        balance0 = web3.fromWei(web3.eth.getBalance(acc0))
+        balance1 = web3.fromWei(web3.eth.getBalance(acc1))
+        if (balance0 >0 && balance1 > 0) {
+            miner.stop()
+            break
+        }
+        sleep(1000)
+    }
+    console.log("[mainnode]: acc0 balance: " + web3.fromWei(web3.eth.getBalance(acc0)))
+    console.log("[mainnode]: acc1 balance: " + web3.fromWei(web3.eth.getBalance(acc1)))
+
+    console.log("[mainnode]: admin.nodeInfo: " + admin.nodeInfo.id)
+
+    sleep(5000)
+}
+
+interaction()
diff --git a/yapen/peernode.js b/yapen/peernode.js
new file mode 100644
index 0000000000..675580630a
--- /dev/null
+++ b/yapen/peernode.js
@@ -0,0 +1,23 @@
+function sleep(milliseconds) {
+  var start = new Date().getTime();
+  for (var i = 0; i < 1e7; i++) {
+    if ((new Date().getTime() - start) > milliseconds){
+      break;
+    }
+  }
+}
+
+function interaction() {
+    console.log("[peermode]: peer count: " + net.peerCount)
+    //admin.addPeer("enode://a321db2296eb0078fab331d27460456f9c66c478049ee34441595d9c4fc4391af31f24b81fcdf21f28a7e391d07ab4fc550b6e235021abad310992f32d2fc876@127.0.0.1:30303")
+
+    console.log("[peermode]: connect to [::]:30303")
+    admin.addPeer("enode://07a0106f92170dd3fc3ffa201c5b0708c8b3b92f73ad58b6f21a43338eea924b53e0a1d942c70f582127f10fb86b569c10dabcc97fa308a90f23aa6003c5b76c@[::]:30303")
+    while (net.peerCount == 0)
+    {
+        sleep(1000)
+        console.log("[peermode]: peer count: " + net.peerCount)
+    }
+}
+
+interaction()