diff --git a/binary/int.go b/binary/int.go
index 4ff9d7cb4..ae03adc7c 100644
--- a/binary/int.go
+++ b/binary/int.go
@@ -160,8 +160,9 @@ func ReadUInt64(r io.Reader, n *int64, err *error) uint64 {
 
 func WriteVarInt(w io.Writer, i int64, n *int64, err *error) {
 	buf := make([]byte, 9)
-	*n += int64(binary.PutVarint(buf, int64(i)))
-	WriteTo(w, buf, n, err)
+	n_ := int64(binary.PutVarint(buf, int64(i)))
+	*n += n_
+	WriteTo(w, buf[:n_], n, err)
 }
 
 func ReadVarInt(r io.Reader, n *int64, err *error) int64 {
@@ -175,8 +176,9 @@ func ReadVarInt(r io.Reader, n *int64, err *error) int64 {
 
 func WriteUVarInt(w io.Writer, i uint64, n *int64, err *error) {
 	buf := make([]byte, 9)
-	*n += int64(binary.PutUvarint(buf, uint64(i)))
-	WriteTo(w, buf, n, err)
+	n_ := int64(binary.PutUvarint(buf, uint64(i)))
+	*n += n_
+	WriteTo(w, buf[:n_], n, err)
 }
 
 func ReadUVarInt(r io.Reader, n *int64, err *error) uint64 {
diff --git a/binary/util.go b/binary/util.go
index e8a52117b..e80c7a0bf 100644
--- a/binary/util.go
+++ b/binary/util.go
@@ -7,7 +7,10 @@ import (
 
 func BinaryBytes(b Binary) []byte {
 	buf := bytes.NewBuffer(nil)
-	b.WriteTo(buf)
+	_, err := b.WriteTo(buf)
+	if err != nil {
+		panic(err)
+	}
 	return buf.Bytes()
 }
 
diff --git a/blocks/block_test.go b/blocks/block_test.go
index 6763c8230..26fe5eba1 100644
--- a/blocks/block_test.go
+++ b/blocks/block_test.go
@@ -3,46 +3,16 @@ package blocks
 import (
 	"bytes"
 	. "github.com/tendermint/tendermint/binary"
-	"math/rand"
+	. "github.com/tendermint/tendermint/common"
 	"testing"
-	"time"
 )
 
-// Distributed pseudo-exponentially to test for various cases
-func randUInt64() uint64 {
-	bits := rand.Uint32() % 64
-	if bits == 0 {
-		return 0
-	}
-	n := uint64(1 << (bits - 1))
-	n += uint64(rand.Int63()) & ((1 << (bits - 1)) - 1)
-	return n
-}
-
-func randUInt32() uint32 {
-	bits := rand.Uint32() % 32
-	if bits == 0 {
-		return 0
-	}
-	n := uint32(1 << (bits - 1))
-	n += uint32(rand.Int31()) & ((1 << (bits - 1)) - 1)
-	return n
-}
-
-func randTime() time.Time {
-	return time.Unix(int64(randUInt64()), 0)
-}
-
-func randBytes(n int) []byte {
-	bs := make([]byte, n)
-	for i := 0; i < n; i++ {
-		bs[i] = byte(rand.Intn(256))
-	}
-	return bs
+func randSig() Signature {
+	return Signature{RandUInt64Exp(), RandBytes(32)}
 }
 
-func randSig() Signature {
-	return Signature{randUInt64(), randBytes(32)}
+func randBaseTx() BaseTx {
+	return BaseTx{0, randSig()}
 }
 
 func TestBlock(t *testing.T) {
@@ -50,48 +20,52 @@ func TestBlock(t *testing.T) {
 	// Account Txs
 
 	sendTx := &SendTx{
-		Signature: randSig(),
-		Fee:       randUInt64(),
-		To:        randUInt64(),
-		Amount:    randUInt64(),
+		BaseTx: randBaseTx(),
+		Fee:    RandUInt64Exp(),
+		To:     RandUInt64Exp(),
+		Amount: RandUInt64Exp(),
 	}
 
 	nameTx := &NameTx{
-		Signature: randSig(),
-		Fee:       randUInt64(),
-		Name:      string(randBytes(12)),
-		PubKey:    randBytes(32),
+		BaseTx: randBaseTx(),
+		Fee:    RandUInt64Exp(),
+		Name:   string(RandBytes(12)),
+		PubKey: RandBytes(32),
 	}
 
 	// Validation Txs
 
-	bond := &Bond{
-		Signature: randSig(),
-		Fee:       randUInt64(),
-		UnbondTo:  randUInt64(),
-		Amount:    randUInt64(),
+	bondTx := &BondTx{
+		BaseTx:   randBaseTx(),
+		Fee:      RandUInt64Exp(),
+		UnbondTo: RandUInt64Exp(),
+		Amount:   RandUInt64Exp(),
 	}
 
-	unbond := &Unbond{
-		Signature: randSig(),
-		Fee:       randUInt64(),
-		Amount:    randUInt64(),
+	unbondTx := &UnbondTx{
+		BaseTx: randBaseTx(),
+		Fee:    RandUInt64Exp(),
+		Amount: RandUInt64Exp(),
 	}
 
-	timeout := &Timeout{
-		AccountId: randUInt64(),
-		Penalty:   randUInt64(),
+	timeoutTx := &TimeoutTx{
+		AccountId: RandUInt64Exp(),
+		Penalty:   RandUInt64Exp(),
 	}
 
-	dupeout := &Dupeout{
-		VoteA: BlockVote{
-			Height:    randUInt64(),
-			BlockHash: randBytes(32),
+	dupeoutTx := &DupeoutTx{
+		VoteA: Vote{
+			Height:    RandUInt32Exp(),
+			Round:     RandUInt16Exp(),
+			Type:      VoteTypeBare,
+			BlockHash: RandBytes(32),
 			Signature: randSig(),
 		},
-		VoteB: BlockVote{
-			Height:    randUInt64(),
-			BlockHash: randBytes(32),
+		VoteB: Vote{
+			Height:    RandUInt32Exp(),
+			Round:     RandUInt16Exp(),
+			Type:      VoteTypeBare,
+			BlockHash: RandBytes(32),
 			Signature: randSig(),
 		},
 	}
@@ -100,30 +74,34 @@ func TestBlock(t *testing.T) {
 
 	block := &Block{
 		Header: Header{
-			Network:        "Tendermint",
-			Height:         randUInt32(),
-			Fees:           randUInt64(),
-			Time:           randTime(),
-			LastBlockHash:  randBytes(32),
-			ValidationHash: randBytes(32),
-			DataHash:       randBytes(32),
+			Network:             "Tendermint",
+			Height:              RandUInt32Exp(),
+			Fees:                RandUInt64Exp(),
+			Time:                RandTime(),
+			LastBlockHash:       RandBytes(32),
+			ValidationStateHash: RandBytes(32),
+			AccountStateHash:    RandBytes(32),
 		},
 		Validation: Validation{
 			Signatures: []Signature{randSig(), randSig()},
-			Txs:        []Txs{bond, unbond, timeout, dupeout},
 		},
 		Data: Data{
-			Txs: []Tx{sendTx, nameTx},
+			Txs: []Tx{sendTx, nameTx, bondTx, unbondTx, timeoutTx, dupeoutTx},
 		},
 	}
 
 	// Write the block, read it in again, write it again.
 	// Then, compare.
+	// TODO We should compute the hash instead, so Block -> Bytes -> Block and compare hashes.
 
 	blockBytes := BinaryBytes(block)
 	var n int64
 	var err error
 	block2 := ReadBlock(bytes.NewReader(blockBytes), &n, &err)
+	if err != nil {
+		t.Errorf("Reading block failed: %v", err)
+	}
+
 	blockBytes2 := BinaryBytes(block2)
 
 	if !bytes.Equal(blockBytes, blockBytes2) {
diff --git a/blocks/codec_test.go b/blocks/codec_test.go
index 8f5482754..1339f1b19 100644
--- a/blocks/codec_test.go
+++ b/blocks/codec_test.go
@@ -15,13 +15,13 @@ func BenchmarkTestCustom(b *testing.B) {
 	b.StopTimer()
 
 	h := &Header{
-		Network:        "Header",
-		Height:         123,
-		Fees:           123,
-		Time:           time.Unix(123, 0),
-		LastBlockHash:  []byte("prevhash"),
-		ValidationHash: []byte("validationhash"),
-		DataHash:       []byte("datahash"),
+		Network:             "Header",
+		Height:              123,
+		Fees:                123,
+		Time:                time.Unix(123, 0),
+		LastBlockHash:       []byte("prevhash"),
+		ValidationStateHash: []byte("validationhash"),
+		AccountStateHash:    []byte("accounthash"),
 	}
 
 	buf := bytes.NewBuffer(nil)
@@ -40,26 +40,26 @@ func BenchmarkTestCustom(b *testing.B) {
 }
 
 type HHeader struct {
-	Network        string `json:"N"`
-	Height         uint64 `json:"H"`
-	Fees           uint64 `json:"F"`
-	Time           uint64 `json:"T"`
-	LastBlockHash  []byte `json:"PH"`
-	ValidationHash []byte `json:"VH"`
-	DataHash       []byte `json:"DH"`
+	Network             string `json:"N"`
+	Height              uint64 `json:"H"`
+	Fees                uint64 `json:"F"`
+	Time                uint64 `json:"T"`
+	LastBlockHash       []byte `json:"PH"`
+	ValidationStateHash []byte `json:"VH"`
+	AccountStateHash    []byte `json:"DH"`
 }
 
 func BenchmarkTestJSON(b *testing.B) {
 	b.StopTimer()
 
 	h := &HHeader{
-		Network:        "Header",
-		Height:         123,
-		Fees:           123,
-		Time:           123,
-		LastBlockHash:  []byte("prevhash"),
-		ValidationHash: []byte("validationhash"),
-		DataHash:       []byte("datahash"),
+		Network:             "Header",
+		Height:              123,
+		Fees:                123,
+		Time:                123,
+		LastBlockHash:       []byte("prevhash"),
+		ValidationStateHash: []byte("validationhash"),
+		AccountStateHash:    []byte("accounthash"),
 	}
 	h2 := &HHeader{}
 
@@ -82,13 +82,13 @@ func BenchmarkTestGob(b *testing.B) {
 	b.StopTimer()
 
 	h := &Header{
-		Network:        "Header",
-		Height:         123,
-		Fees:           123,
-		Time:           time.Unix(123, 0),
-		LastBlockHash:  []byte("prevhash"),
-		ValidationHash: []byte("validationhash"),
-		DataHash:       []byte("datahash"),
+		Network:             "Header",
+		Height:              123,
+		Fees:                123,
+		Time:                time.Unix(123, 0),
+		LastBlockHash:       []byte("prevhash"),
+		ValidationStateHash: []byte("validationhash"),
+		AccountStateHash:    []byte("datahash"),
 	}
 	h2 := &Header{}
 
@@ -111,13 +111,13 @@ func BenchmarkTestMsgPack(b *testing.B) {
 	b.StopTimer()
 
 	h := &Header{
-		Network:        "Header",
-		Height:         123,
-		Fees:           123,
-		Time:           time.Unix(123, 0),
-		LastBlockHash:  []byte("prevhash"),
-		ValidationHash: []byte("validationhash"),
-		DataHash:       []byte("datahash"),
+		Network:             "Header",
+		Height:              123,
+		Fees:                123,
+		Time:                time.Unix(123, 0),
+		LastBlockHash:       []byte("prevhash"),
+		ValidationStateHash: []byte("validationhash"),
+		AccountStateHash:    []byte("datahash"),
 	}
 	h2 := &Header{}
 
@@ -140,13 +140,13 @@ func BenchmarkTestMsgPack2(b *testing.B) {
 	b.StopTimer()
 
 	h := &Header{
-		Network:        "Header",
-		Height:         123,
-		Fees:           123,
-		Time:           time.Unix(123, 0),
-		LastBlockHash:  []byte("prevhash"),
-		ValidationHash: []byte("validationhash"),
-		DataHash:       []byte("datahash"),
+		Network:             "Header",
+		Height:              123,
+		Fees:                123,
+		Time:                time.Unix(123, 0),
+		LastBlockHash:       []byte("prevhash"),
+		ValidationStateHash: []byte("validationhash"),
+		AccountStateHash:    []byte("accounthash"),
 	}
 	h2 := &Header{}
 	var mh codec.MsgpackHandle
diff --git a/blocks/tx.go b/blocks/tx.go
index 2df41b428..bd69cadc8 100644
--- a/blocks/tx.go
+++ b/blocks/tx.go
@@ -28,59 +28,59 @@ type Tx interface {
 
 const (
 	// Account transactions
-	TX_TYPE_SEND = byte(0x01)
-	TX_TYPE_NAME = byte(0x02)
+	txTypeSend = byte(0x01)
+	txTypeName = byte(0x02)
 
 	// Validation transactions
-	TX_TYPE_BOND    = byte(0x11)
-	TX_TYPE_UNBOND  = byte(0x12)
-	TX_TYPE_TIMEOUT = byte(0x13)
-	TX_TYPE_DUPEOUT = byte(0x14)
+	txTypeBond    = byte(0x11)
+	txTypeUnbond  = byte(0x12)
+	txTypeTimeout = byte(0x13)
+	txTypeDupeout = byte(0x14)
 )
 
 func ReadTx(r io.Reader, n *int64, err *error) Tx {
 	switch t := ReadByte(r, n, err); t {
-	case TX_TYPE_SEND:
+	case txTypeSend:
 		return &SendTx{
 			BaseTx: ReadBaseTx(r, n, err),
 			Fee:    ReadUInt64(r, n, err),
 			To:     ReadUInt64(r, n, err),
 			Amount: ReadUInt64(r, n, err),
 		}
-	case TX_TYPE_NAME:
+	case txTypeName:
 		return &NameTx{
 			BaseTx: ReadBaseTx(r, n, err),
 			Fee:    ReadUInt64(r, n, err),
 			Name:   ReadString(r, n, err),
 			PubKey: ReadByteSlice(r, n, err),
 		}
-	case TX_TYPE_BOND:
+	case txTypeBond:
 		return &BondTx{
 			BaseTx:   ReadBaseTx(r, n, err),
 			Fee:      ReadUInt64(r, n, err),
 			UnbondTo: ReadUInt64(r, n, err),
 			Amount:   ReadUInt64(r, n, err),
 		}
-	case TX_TYPE_UNBOND:
+	case txTypeUnbond:
 		return &UnbondTx{
 			BaseTx: ReadBaseTx(r, n, err),
 			Fee:    ReadUInt64(r, n, err),
 			Amount: ReadUInt64(r, n, err),
 		}
-	case TX_TYPE_TIMEOUT:
+	case txTypeTimeout:
 		return &TimeoutTx{
 			BaseTx:    ReadBaseTx(r, n, err),
 			AccountId: ReadUInt64(r, n, err),
 			Penalty:   ReadUInt64(r, n, err),
 		}
-	case TX_TYPE_DUPEOUT:
+	case txTypeDupeout:
 		return &DupeoutTx{
 			BaseTx: ReadBaseTx(r, n, err),
 			VoteA:  *ReadVote(r, n, err),
 			VoteB:  *ReadVote(r, n, err),
 		}
 	default:
-		Panicf("Unknown Tx type %x", t)
+		*err = Errorf("Unknown Tx type %X", t)
 		return nil
 	}
 }
@@ -123,7 +123,7 @@ type SendTx struct {
 }
 
 func (tx *SendTx) Type() byte {
-	return TX_TYPE_SEND
+	return txTypeSend
 }
 
 func (tx *SendTx) WriteTo(w io.Writer) (n int64, err error) {
@@ -145,7 +145,7 @@ type NameTx struct {
 }
 
 func (tx *NameTx) Type() byte {
-	return TX_TYPE_NAME
+	return txTypeName
 }
 
 func (tx *NameTx) WriteTo(w io.Writer) (n int64, err error) {
@@ -167,7 +167,7 @@ type BondTx struct {
 }
 
 func (tx *BondTx) Type() byte {
-	return TX_TYPE_BOND
+	return txTypeBond
 }
 
 func (tx *BondTx) WriteTo(w io.Writer) (n int64, err error) {
@@ -188,7 +188,7 @@ type UnbondTx struct {
 }
 
 func (tx *UnbondTx) Type() byte {
-	return TX_TYPE_UNBOND
+	return txTypeUnbond
 }
 
 func (tx *UnbondTx) WriteTo(w io.Writer) (n int64, err error) {
@@ -208,7 +208,7 @@ type TimeoutTx struct {
 }
 
 func (tx *TimeoutTx) Type() byte {
-	return TX_TYPE_TIMEOUT
+	return txTypeTimeout
 }
 
 func (tx *TimeoutTx) WriteTo(w io.Writer) (n int64, err error) {
@@ -228,7 +228,7 @@ type DupeoutTx struct {
 }
 
 func (tx *DupeoutTx) Type() byte {
-	return TX_TYPE_DUPEOUT
+	return txTypeDupeout
 }
 
 func (tx *DupeoutTx) WriteTo(w io.Writer) (n int64, err error) {
diff --git a/common/random.go b/common/random.go
index d68ac6da5..2588db623 100644
--- a/common/random.go
+++ b/common/random.go
@@ -4,6 +4,7 @@ import (
 	crand "crypto/rand"
 	"encoding/hex"
 	"math/rand"
+	"time"
 )
 
 const (
@@ -12,7 +13,7 @@ const (
 
 func init() {
 	// Seed math/rand with "secure" int64
-	b := RandBytes(8)
+	b := CRandBytes(8)
 	var seed uint64
 	for i := 0; i < 8; i++ {
 		seed |= uint64(b[i])
@@ -22,7 +23,6 @@ func init() {
 }
 
 // Constructs an alphanumeric string of given length.
-// Not crypto safe
 func RandStr(length int) string {
 	chars := []byte{}
 MAIN_LOOP:
@@ -46,8 +46,67 @@ MAIN_LOOP:
 	return string(chars)
 }
 
-// Crypto safe
-func RandBytes(numBytes int) []byte {
+func RandUInt16() uint16 {
+	return uint16(rand.Uint32() & (1<<16 - 1))
+}
+
+func RandUInt32() uint32 {
+	return rand.Uint32()
+}
+
+func RandUInt64() uint64 {
+	return uint64(rand.Uint32())<<32 + uint64(rand.Uint32())
+}
+
+// Distributed pseudo-exponentially to test for various cases
+func RandUInt16Exp() uint16 {
+	bits := rand.Uint32() % 16
+	if bits == 0 {
+		return 0
+	}
+	n := uint16(1 << (bits - 1))
+	n += uint16(rand.Int31()) & ((1 << (bits - 1)) - 1)
+	return n
+}
+
+// Distributed pseudo-exponentially to test for various cases
+func RandUInt32Exp() uint32 {
+	bits := rand.Uint32() % 32
+	if bits == 0 {
+		return 0
+	}
+	n := uint32(1 << (bits - 1))
+	n += uint32(rand.Int31()) & ((1 << (bits - 1)) - 1)
+	return n
+}
+
+// Distributed pseudo-exponentially to test for various cases
+func RandUInt64Exp() uint64 {
+	bits := rand.Uint32() % 64
+	if bits == 0 {
+		return 0
+	}
+	n := uint64(1 << (bits - 1))
+	n += uint64(rand.Int63()) & ((1 << (bits - 1)) - 1)
+	return n
+}
+
+func RandTime() time.Time {
+	return time.Unix(int64(RandUInt64Exp()), 0)
+}
+
+func RandBytes(n int) []byte {
+	bs := make([]byte, n)
+	for i := 0; i < n; i++ {
+		bs[i] = byte(rand.Intn(256))
+	}
+	return bs
+}
+
+//-----------------------------------------------------------------------------
+// CRand* methods are crypto safe.
+
+func CRandBytes(numBytes int) []byte {
 	b := make([]byte, numBytes)
 	_, err := crand.Read(b)
 	if err != nil {
@@ -56,8 +115,7 @@ func RandBytes(numBytes int) []byte {
 	return b
 }
 
-// Crypto safe
 // RandHex(24) gives 96 bits of randomness, strong enough for most purposes.
-func RandHex(numDigits int) string {
-	return hex.EncodeToString(RandBytes(numDigits / 2))
+func CRandHex(numDigits int) string {
+	return hex.EncodeToString(CRandBytes(numDigits / 2))
 }
diff --git a/consensus/consensus.go b/consensus/consensus.go
index 1205ba490..0d3ffdf3b 100644
--- a/consensus/consensus.go
+++ b/consensus/consensus.go
@@ -142,25 +142,16 @@ func (conR *ConsensusReactor) GetChannels() []*p2p.ChannelDescriptor {
 	// TODO optimize
 	return []*p2p.ChannelDescriptor{
 		&p2p.ChannelDescriptor{
-			Id:                StateCh,
-			SendQueueCapacity: 1,
-			RecvQueueCapacity: 10,
-			RecvBufferSize:    10240,
-			DefaultPriority:   5,
+			Id:       StateCh,
+			Priority: 5,
 		},
 		&p2p.ChannelDescriptor{
-			Id:                DataCh,
-			SendQueueCapacity: 1,
-			RecvQueueCapacity: 10,
-			RecvBufferSize:    10240,
-			DefaultPriority:   5,
+			Id:       DataCh,
+			Priority: 5,
 		},
 		&p2p.ChannelDescriptor{
-			Id:                VoteCh,
-			SendQueueCapacity: 1,
-			RecvQueueCapacity: 1000,
-			RecvBufferSize:    10240,
-			DefaultPriority:   5,
+			Id:       VoteCh,
+			Priority: 5,
 		},
 	}
 }
diff --git a/db/db.go b/db/db.go
index 84122d049..d44f4078d 100644
--- a/db/db.go
+++ b/db/db.go
@@ -1,6 +1,6 @@
 package db
 
-type Db interface {
+type DB interface {
 	Get([]byte) []byte
 	Set([]byte, []byte)
 }
diff --git a/p2p/addrbook.go b/p2p/addrbook.go
index 493fb0f38..44e2538fd 100644
--- a/p2p/addrbook.go
+++ b/p2p/addrbook.go
@@ -112,7 +112,7 @@ func NewAddrBook(filePath string) *AddrBook {
 
 // When modifying this, don't forget to update loadFromFile()
 func (a *AddrBook) init() {
-	a.key = RandHex(24) // 24/2 * 8 = 96 bits
+	a.key = CRandHex(24) // 24/2 * 8 = 96 bits
 	// New addr buckets
 	a.addrNew = make([]map[string]*knownAddress, newBucketCount)
 	for i := range a.addrNew {
diff --git a/p2p/connection.go b/p2p/connection.go
index 6f35eff42..f9aabf554 100644
--- a/p2p/connection.go
+++ b/p2p/connection.go
@@ -16,15 +16,17 @@ import (
 )
 
 const (
-	numBatchPackets    = 10
-	minReadBufferSize  = 1024
-	minWriteBufferSize = 1024
-	flushThrottleMS    = 50
-	idleTimeoutMinutes = 5
-	updateStatsSeconds = 2
-	pingTimeoutMinutes = 2
-	defaultSendRate    = 51200 // 5Kb/s
-	defaultRecvRate    = 51200 // 5Kb/s
+	numBatchPackets           = 10
+	minReadBufferSize         = 1024
+	minWriteBufferSize        = 1024
+	flushThrottleMS           = 50
+	idleTimeoutMinutes        = 5
+	updateStatsSeconds        = 2
+	pingTimeoutMinutes        = 2
+	defaultSendRate           = 51200 // 5Kb/s
+	defaultRecvRate           = 51200 // 5Kb/s
+	defaultSendQueueCapacity  = 1
+	defaultRecvBufferCapacity = 4096
 )
 
 type receiveCbFunc func(chId byte, msgBytes []byte)
@@ -399,11 +401,8 @@ FOR_LOOP:
 //-----------------------------------------------------------------------------
 
 type ChannelDescriptor struct {
-	Id                byte
-	SendQueueCapacity int // One per MConnection.
-	RecvQueueCapacity int // Global for this channel.
-	RecvBufferSize    int
-	DefaultPriority   uint
+	Id       byte
+	Priority uint
 }
 
 // TODO: lowercase.
@@ -421,16 +420,16 @@ type Channel struct {
 }
 
 func newChannel(conn *MConnection, desc *ChannelDescriptor) *Channel {
-	if desc.DefaultPriority <= 0 {
+	if desc.Priority <= 0 {
 		panic("Channel default priority must be a postive integer")
 	}
 	return &Channel{
 		conn:      conn,
 		desc:      desc,
 		id:        desc.Id,
-		sendQueue: make(chan []byte, desc.SendQueueCapacity),
-		recving:   make([]byte, 0, desc.RecvBufferSize),
-		priority:  desc.DefaultPriority,
+		sendQueue: make(chan []byte, defaultSendQueueCapacity),
+		recving:   make([]byte, 0, defaultRecvBufferCapacity),
+		priority:  desc.Priority,
 	}
 }
 
@@ -462,7 +461,7 @@ func (ch *Channel) loadSendQueueSize() (size int) {
 // Goroutine-safe
 // Use only as a heuristic.
 func (ch *Channel) canSend() bool {
-	return ch.loadSendQueueSize() < ch.desc.SendQueueCapacity
+	return ch.loadSendQueueSize() < defaultSendQueueCapacity
 }
 
 // Returns true if any packets are pending to be sent.
@@ -513,7 +512,7 @@ func (ch *Channel) recvPacket(pkt packet) []byte {
 	ch.recving = append(ch.recving, pkt.Bytes...)
 	if pkt.EOF == byte(0x01) {
 		msgBytes := ch.recving
-		ch.recving = make([]byte, 0, ch.desc.RecvBufferSize)
+		ch.recving = make([]byte, 0, defaultRecvBufferCapacity)
 		return msgBytes
 	}
 	return nil
diff --git a/p2p/pex_reactor.go b/p2p/pex_reactor.go
index da86f20bf..e0c0713ba 100644
--- a/p2p/pex_reactor.go
+++ b/p2p/pex_reactor.go
@@ -68,14 +68,10 @@ func (pexR *PEXReactor) SendAddrs(peer *Peer, addrs []*NetAddress) {
 
 // Implements Reactor
 func (pexR *PEXReactor) GetChannels() []*ChannelDescriptor {
-	// TODO optimize
 	return []*ChannelDescriptor{
 		&ChannelDescriptor{
-			Id:                PexCh,
-			SendQueueCapacity: 1,
-			RecvQueueCapacity: 2,
-			RecvBufferSize:    1024,
-			DefaultPriority:   1,
+			Id:       PexCh,
+			Priority: 1,
 		},
 	}
 }
diff --git a/p2p/switch.go b/p2p/switch.go
index 565d2c16d..9d55c1f49 100644
--- a/p2p/switch.go
+++ b/p2p/switch.go
@@ -105,6 +105,10 @@ func (s *Switch) Stop() {
 	}
 }
 
+func (s *Switch) Reactors() []Reactor {
+	return s.reactors
+}
+
 func (s *Switch) AddPeerWithConnection(conn net.Conn, outbound bool) (*Peer, error) {
 	if atomic.LoadUint32(&s.stopped) == 1 {
 		return nil, ErrSwitchStopped
diff --git a/p2p/switch_test.go b/p2p/switch_test.go
index 612ca3126..33745a9de 100644
--- a/p2p/switch_test.go
+++ b/p2p/switch_test.go
@@ -2,8 +2,8 @@ package p2p
 
 import (
 	"bytes"
-	"encoding/hex"
 	"io"
+	"sync"
 	"testing"
 	"time"
 
@@ -17,30 +17,66 @@ func (s String) WriteTo(w io.Writer) (n int64, err error) {
 	return
 }
 
-// convenience method for creating two switches connected to each other.
-func makeSwitchPair(t testing.TB, numChannels int, sendQueueCapacity int, recvBufferSize int, recvQueueCapacity int) (*Switch, *Switch, []*ChannelDescriptor) {
+//-----------------------------------------------------------------------------
+
+type PeerMessage struct {
+	PeerKey string
+	Bytes   []byte
+	Counter int
+}
 
-	// Make numChannels channels starting at byte(0x00)
-	chIds := []byte{}
-	for i := 0; i < numChannels; i++ {
-		chIds = append(chIds, byte(i))
+type TestReactor struct {
+	mtx          sync.Mutex
+	channels     []*ChannelDescriptor
+	peersAdded   []*Peer
+	peersRemoved []*Peer
+	logMessages  bool
+	msgsCounter  int
+	msgsReceived map[byte][]PeerMessage
+}
+
+func NewTestReactor(channels []*ChannelDescriptor, logMessages bool) *TestReactor {
+	return &TestReactor{
+		channels:     channels,
+		logMessages:  logMessages,
+		msgsReceived: make(map[byte][]PeerMessage),
 	}
+}
+
+func (tr *TestReactor) GetChannels() []*ChannelDescriptor {
+	return tr.channels
+}
+
+func (tr *TestReactor) AddPeer(peer *Peer) {
+	tr.mtx.Lock()
+	defer tr.mtx.Unlock()
+	tr.peersAdded = append(tr.peersAdded, peer)
+}
 
-	// Make some channel descriptors.
-	chDescs := []*ChannelDescriptor{}
-	for _, chId := range chIds {
-		chDescs = append(chDescs, &ChannelDescriptor{
-			Id:                chId,
-			SendQueueCapacity: sendQueueCapacity,
-			RecvBufferSize:    recvBufferSize,
-			RecvQueueCapacity: recvQueueCapacity,
-			DefaultPriority:   1,
-		})
+func (tr *TestReactor) RemovePeer(peer *Peer, reason interface{}) {
+	tr.mtx.Lock()
+	defer tr.mtx.Unlock()
+	tr.peersRemoved = append(tr.peersRemoved, peer)
+}
+
+func (tr *TestReactor) Receive(chId byte, peer *Peer, msgBytes []byte) {
+	if tr.logMessages {
+		tr.mtx.Lock()
+		defer tr.mtx.Unlock()
+		//fmt.Printf("Received: %X, %X\n", chId, msgBytes)
+		tr.msgsReceived[chId] = append(tr.msgsReceived[chId], PeerMessage{peer.Key, msgBytes, tr.msgsCounter})
+		tr.msgsCounter++
 	}
+}
+
+//-----------------------------------------------------------------------------
+
+// convenience method for creating two switches connected to each other.
+func makeSwitchPair(t testing.TB, reactorsGenerator func() []Reactor) (*Switch, *Switch) {
 
 	// Create two switches that will be interconnected.
-	s1 := NewSwitch(chDescs)
-	s2 := NewSwitch(chDescs)
+	s1 := NewSwitch(reactorsGenerator())
+	s2 := NewSwitch(reactorsGenerator())
 
 	// Create a listener for s1
 	l := NewDefaultListener("tcp", ":8001")
@@ -67,11 +103,23 @@ func makeSwitchPair(t testing.TB, numChannels int, sendQueueCapacity int, recvBu
 	// Close the server, no longer needed.
 	l.Stop()
 
-	return s1, s2, chDescs
+	return s1, s2
 }
 
 func TestSwitches(t *testing.T) {
-	s1, s2, _ := makeSwitchPair(t, 10, 10, 1024, 10)
+	s1, s2 := makeSwitchPair(t, func() []Reactor {
+		// Make two reactors of two channels each
+		reactors := make([]Reactor, 2)
+		reactors[0] = NewTestReactor([]*ChannelDescriptor{
+			&ChannelDescriptor{Id: byte(0x00), Priority: 10},
+			&ChannelDescriptor{Id: byte(0x01), Priority: 10},
+		}, true)
+		reactors[1] = NewTestReactor([]*ChannelDescriptor{
+			&ChannelDescriptor{Id: byte(0x02), Priority: 10},
+			&ChannelDescriptor{Id: byte(0x03), Priority: 10},
+		}, true)
+		return reactors
+	})
 	defer s1.Stop()
 	defer s2.Stop()
 
@@ -83,61 +131,66 @@ func TestSwitches(t *testing.T) {
 		t.Errorf("Expected exactly 1 peer in s2, got %v", s2.Peers().Size())
 	}
 
-	// Broadcast a message on ch0
-	s1.Broadcast(byte(0x00), String("channel zero"))
-	// Broadcast a message on ch1
-	s1.Broadcast(byte(0x01), String("channel one"))
-	// Broadcast a message on ch2
-	s1.Broadcast(byte(0x02), String("channel two"))
+	ch0Msg := String("channel zero")
+	ch1Msg := String("channel one")
+	ch2Msg := String("channel two")
+
+	s1.Broadcast(byte(0x00), ch0Msg)
+	s1.Broadcast(byte(0x01), ch1Msg)
+	s1.Broadcast(byte(0x02), ch2Msg)
 
 	// Wait for things to settle...
 	time.Sleep(100 * time.Millisecond)
 
-	// Receive message from channel 1 and check
-	inMsg, ok := s2.Receive(byte(0x01))
-	var n int64
-	var err error
-	if !ok {
-		t.Errorf("Failed to receive from channel one")
+	// Check message on ch0
+	ch0Msgs := s2.Reactors()[0].(*TestReactor).msgsReceived[byte(0x00)]
+	if len(ch0Msgs) != 1 {
+		t.Errorf("Expected to have received 1 message in ch0")
 	}
-	if ReadString(bytes.NewBuffer(inMsg.Bytes), &n, &err) != "channel one" {
-		t.Errorf("Unexpected received message bytes:\n%v", hex.Dump(inMsg.Bytes))
+	if !bytes.Equal(ch0Msgs[0].Bytes, BinaryBytes(ch0Msg)) {
+		t.Errorf("Unexpected message bytes. Wanted: %X, Got: %X", BinaryBytes(ch0Msg), ch0Msgs[0].Bytes)
 	}
 
-	// Receive message from channel 0 and check
-	inMsg, ok = s2.Receive(byte(0x00))
-	if !ok {
-		t.Errorf("Failed to receive from channel zero")
+	// Check message on ch1
+	ch1Msgs := s2.Reactors()[0].(*TestReactor).msgsReceived[byte(0x01)]
+	if len(ch1Msgs) != 1 {
+		t.Errorf("Expected to have received 1 message in ch1")
+	}
+	if !bytes.Equal(ch1Msgs[0].Bytes, BinaryBytes(ch1Msg)) {
+		t.Errorf("Unexpected message bytes. Wanted: %X, Got: %X", BinaryBytes(ch1Msg), ch1Msgs[0].Bytes)
 	}
-	if ReadString(bytes.NewBuffer(inMsg.Bytes), &n, &err) != "channel zero" {
-		t.Errorf("Unexpected received message bytes:\n%v", hex.Dump(inMsg.Bytes))
+
+	// Check message on ch2
+	ch2Msgs := s2.Reactors()[1].(*TestReactor).msgsReceived[byte(0x02)]
+	if len(ch2Msgs) != 1 {
+		t.Errorf("Expected to have received 1 message in ch2")
 	}
+	if !bytes.Equal(ch2Msgs[0].Bytes, BinaryBytes(ch2Msg)) {
+		t.Errorf("Unexpected message bytes. Wanted: %X, Got: %X", BinaryBytes(ch2Msg), ch2Msgs[0].Bytes)
+	}
+
 }
 
 func BenchmarkSwitches(b *testing.B) {
 
 	b.StopTimer()
 
-	s1, s2, chDescs := makeSwitchPair(b, 10, 10, 1024, 10)
+	s1, s2 := makeSwitchPair(b, func() []Reactor {
+		// Make two reactors of two channels each
+		reactors := make([]Reactor, 2)
+		reactors[0] = NewTestReactor([]*ChannelDescriptor{
+			&ChannelDescriptor{Id: byte(0x00), Priority: 10},
+			&ChannelDescriptor{Id: byte(0x01), Priority: 10},
+		}, false)
+		reactors[1] = NewTestReactor([]*ChannelDescriptor{
+			&ChannelDescriptor{Id: byte(0x02), Priority: 10},
+			&ChannelDescriptor{Id: byte(0x03), Priority: 10},
+		}, false)
+		return reactors
+	})
 	defer s1.Stop()
 	defer s2.Stop()
 
-	// Create a sink on either channel to just pop off messages.
-	recvRoutine := func(c *Switch, chId byte) {
-		for {
-			_, ok := c.Receive(chId)
-			if !ok {
-				break
-			}
-		}
-	}
-
-	// Create routines to consume from recvQueues.
-	for _, chDesc := range chDescs {
-		go recvRoutine(s1, chDesc.Id)
-		go recvRoutine(s2, chDesc.Id)
-	}
-
 	// Allow time for goroutines to boot up
 	time.Sleep(1000 * time.Millisecond)
 	b.StartTimer()
@@ -146,7 +199,7 @@ func BenchmarkSwitches(b *testing.B) {
 
 	// Send random message from one channel to another
 	for i := 0; i < b.N; i++ {
-		chId := chDescs[i%len(chDescs)].Id
+		chId := byte(i % 4)
 		nS, nF := s1.Broadcast(chId, String("test data"))
 		numSuccess += nS
 		numFailure += nF
diff --git a/state/account.go b/state/account.go
index 6a94b8b8a..707a4db7d 100644
--- a/state/account.go
+++ b/state/account.go
@@ -8,19 +8,30 @@ import (
 	"io"
 )
 
+const (
+	AccountBalanceStatusNominal = byte(0x00)
+	AccountBalanceStatusBonded  = byte(0x01)
+)
+
 type Account struct {
 	Id     uint64 // Numeric id of account, incrementing.
 	PubKey []byte
 }
 
-func ReadAccount(r io.Reader, n *int64, err *error) *Account {
-	return &Account{
+func ReadAccount(r io.Reader, n *int64, err *error) Account {
+	return Account{
 		Id:     ReadUInt64(r, n, err),
 		PubKey: ReadByteSlice(r, n, err),
 	}
 }
 
-func (account *Account) Verify(msg []byte, sig Signature) bool {
+func (account Account) WriteTo(w io.Writer) (n int64, err error) {
+	WriteUInt64(w, account.Id, &n, &err)
+	WriteByteSlice(w, account.PubKey, &n, &err)
+	return
+}
+
+func (account Account) Verify(msg []byte, sig Signature) bool {
 	if sig.SignerId != account.Id {
 		panic("Account.Id doesn't match sig.SignerId")
 	}
@@ -38,6 +49,22 @@ func (account *Account) Verify(msg []byte, sig Signature) bool {
 type AccountBalance struct {
 	Account
 	Balance uint64
+	Status  byte
+}
+
+func ReadAccountBalance(r io.Reader, n *int64, err *error) *AccountBalance {
+	return &AccountBalance{
+		Account: ReadAccount(r, n, err),
+		Balance: ReadUInt64(r, n, err),
+		Status:  ReadByte(r, n, err),
+	}
+}
+
+func (accBal AccountBalance) WriteTo(w io.Writer) (n int64, err error) {
+	WriteBinary(w, accBal.Account, &n, &err)
+	WriteUInt64(w, accBal.Balance, &n, &err)
+	WriteByte(w, accBal.Status, &n, &err)
+	return
 }
 
 //-----------------------------------------------------------------------------
@@ -50,7 +77,7 @@ type PrivAccount struct {
 // Generates a new account with private key.
 // The Account.Id is empty since it isn't in the blockchain.
 func GenPrivAccount() *PrivAccount {
-	privKey := RandBytes(32)
+	privKey := CRandBytes(32)
 	pubKey := crypto.MakePubKey(privKey)
 	return &PrivAccount{
 		Account: Account{
diff --git a/state/account_test.go b/state/account_test.go
index 78abec04d..528097052 100644
--- a/state/account_test.go
+++ b/state/account_test.go
@@ -10,7 +10,7 @@ func TestSignAndValidate(t *testing.T) {
 	privAccount := GenPrivAccount()
 	account := &privAccount.Account
 
-	msg := RandBytes(128)
+	msg := CRandBytes(128)
 	sig := privAccount.Sign(msg)
 	t.Logf("msg: %X, sig: %X", msg, sig)
 
diff --git a/state/state.go b/state/state.go
index 06d44ee35..1db32bb13 100644
--- a/state/state.go
+++ b/state/state.go
@@ -8,7 +8,7 @@ import (
 
 	. "github.com/tendermint/tendermint/binary"
 	. "github.com/tendermint/tendermint/blocks"
-	db_ "github.com/tendermint/tendermint/db"
+	. "github.com/tendermint/tendermint/db"
 	"github.com/tendermint/tendermint/merkle"
 )
 
@@ -20,7 +20,7 @@ var (
 
 type State struct {
 	mtx        sync.Mutex
-	db         db_.Db
+	db         DB
 	height     uint32 // Last known block height
 	blockHash  []byte // Last known block hash
 	commitTime time.Time
@@ -28,11 +28,35 @@ type State struct {
 	validators *ValidatorSet
 }
 
-func GenesisState(commitTime time.Time, accounts merkle.Tree, validators *ValidatorSet) *State {
+func GenesisState(db DB, genesisTime time.Time, accountBalances []*AccountBalance) *State {
+
+	accounts := merkle.NewIAVLTree(db)
+	validators := map[uint64]*Validator{}
+
+	for _, account := range accountBalances {
+		// XXX make codec merkle tree.
+		//accounts.Set(account.Id, BinaryBytes(account))
+		validators[account.Id] = &Validator{
+			Account:     account.Account,
+			BondHeight:  0,
+			VotingPower: account.Balance,
+			Accum:       0,
+		}
+	}
+	validatorSet := NewValidatorSet(validators)
+
+	return &State{
+		db:         db,
+		height:     0,
+		blockHash:  nil,
+		commitTime: genesisTime,
+		accounts:   accounts,
+		validators: validatorSet,
+	}
 }
 
-func LoadState(db db_.Db) *State {
-	s := &State{}
+func LoadState(db DB) *State {
+	s := &State{db: db}
 	buf := db.Get(stateKey)
 	if len(buf) == 0 {
 		return nil
@@ -160,7 +184,7 @@ func (s *State) Validators() *ValidatorSet {
 	return s.validators
 }
 
-func (s *State) Account(accountId uint64) (*Account, error) {
+func (s *State) AccountBalance(accountId uint64) (*AccountBalance, error) {
 	s.mtx.Lock()
 	defer s.mtx.Unlock()
 	idBytes, err := BasicCodec.Write(accountId)
@@ -172,6 +196,6 @@ func (s *State) Account(accountId uint64) (*Account, error) {
 		return nil, nil
 	}
 	n, err := int64(0), error(nil)
-	account := ReadAccount(bytes.NewBuffer(accountBytes), &n, &err)
-	return account, err
+	accountBalance := ReadAccountBalance(bytes.NewBuffer(accountBytes), &n, &err)
+	return accountBalance, err
 }
diff --git a/state/state_test.go b/state/state_test.go
new file mode 100644
index 000000000..3a0bd5f02
--- /dev/null
+++ b/state/state_test.go
@@ -0,0 +1,42 @@
+package state
+
+import (
+	. "github.com/tendermint/tendermint/common"
+	. "github.com/tendermint/tendermint/db"
+
+	"testing"
+	"time"
+)
+
+func randAccountBalance(id uint64, status byte) *AccountBalance {
+	return &AccountBalance{
+		Account: Account{
+			Id:     id,
+			PubKey: CRandBytes(32),
+		},
+		Balance: RandUInt64(),
+		Status:  status,
+	}
+}
+
+// The first numValidators accounts are validators.
+func randGenesisState(numAccounts int, numValidators int) *State {
+	db := NewMemDB()
+	accountBalances := make([]*AccountBalance, numAccounts)
+	for i := 0; i < numAccounts; i++ {
+		if i < numValidators {
+			accountBalances[i] = randAccountBalance(uint64(i), AccountBalanceStatusNominal)
+		} else {
+			accountBalances[i] = randAccountBalance(uint64(i), AccountBalanceStatusBonded)
+		}
+	}
+	s0 := GenesisState(db, time.Now(), accountBalances)
+	return s0
+}
+
+func TestGenesisSaveLoad(t *testing.T) {
+
+	s0 := randGenesisState(10, 5)
+	t.Log(s0)
+
+}
diff --git a/state/validator.go b/state/validator.go
index 9f493de69..8154795ef 100644
--- a/state/validator.go
+++ b/state/validator.go
@@ -12,7 +12,7 @@ import (
 // TODO consider moving this to another common types package.
 type Validator struct {
 	Account
-	BondHeight  uint32
+	BondHeight  uint32 // TODO: is this needed?
 	VotingPower uint64
 	Accum       int64
 }
@@ -20,10 +20,7 @@ type Validator struct {
 // Used to persist the state of ConsensusStateControl.
 func ReadValidator(r io.Reader, n *int64, err *error) *Validator {
 	return &Validator{
-		Account: Account{
-			Id:     ReadUInt64(r, n, err),
-			PubKey: ReadByteSlice(r, n, err),
-		},
+		Account:     ReadAccount(r, n, err),
 		BondHeight:  ReadUInt32(r, n, err),
 		VotingPower: ReadUInt64(r, n, err),
 		Accum:       ReadInt64(r, n, err),
@@ -42,8 +39,7 @@ func (v *Validator) Copy() *Validator {
 
 // Used to persist the state of ConsensusStateControl.
 func (v *Validator) WriteTo(w io.Writer) (n int64, err error) {
-	WriteUInt64(w, v.Id, &n, &err)
-	WriteByteSlice(w, v.PubKey, &n, &err)
+	WriteBinary(w, v.Account, &n, &err)
 	WriteUInt32(w, v.BondHeight, &n, &err)
 	WriteUInt64(w, v.VotingPower, &n, &err)
 	WriteInt64(w, v.Accum, &n, &err)