diff --git a/docker/dev.Dockerfile b/docker/dev.Dockerfile
index 8e65a7e..b62e3ce 100644
--- a/docker/dev.Dockerfile
+++ b/docker/dev.Dockerfile
@@ -5,4 +5,4 @@ RUN apk add git python3 make
 RUN go get -d -v .
 RUN make deps
 
-CMD ["sh"]
\ No newline at end of file
+CMD ["sh"]
diff --git a/main.go b/main.go
index e34f2f1..eaca5ff 100644
--- a/main.go
+++ b/main.go
@@ -27,14 +27,15 @@ import (
 )
 
 type ShardIDType = int64
+type PBInt = int64
 
 const numShards ShardIDType = 100
 
-func makeKey(seed int64) (ic.PrivKey, peer.ID, error) {
+func makeKey(seed int) (ic.PrivKey, peer.ID, error) {
 	// If the seed is zero, use real cryptographic randomness. Otherwise, use a
 	// deterministic randomness source to make generated keys stay the same
 	// across multiple runs
-	r := mrand.New(mrand.NewSource(seed))
+	r := mrand.New(mrand.NewSource(int64(seed)))
 	// r := rand.Reader
 
 	// Generate a key pair for this host. We will use it at least
@@ -57,7 +58,7 @@ func makeKey(seed int64) (ic.PrivKey, peer.ID, error) {
 func makeNode(
 	ctx context.Context,
 	listenPort int,
-	randseed int64,
+	randseed int,
 	doBootstrapping bool,
 	bootstrapPeers []pstore.PeerInfo) (*Node, error) {
 	// FIXME: should be set to localhost if we don't want to expose it to outside
@@ -117,7 +118,7 @@ func main() {
 
 	// Parse options from the command line
 
-	seed := flag.Int64("seed", 0, "set random seed for id generation")
+	seed := flag.Int("seed", 0, "set random seed for id generation")
 	listenPort := flag.Int(
 		"port",
 		defaultListenPort,
@@ -146,7 +147,7 @@ func main() {
 
 func runServer(
 	listenPort int,
-	seed int64,
+	seed int,
 	doBootstrapping bool,
 	bootnodes []pstore.PeerInfo,
 	rpcAddr string) {
@@ -178,7 +179,7 @@ func runClient(rpcAddr string, cliArgs []string) {
 		}
 		targetIP := rpcArgs[0]
 		targetPort, err := strconv.Atoi(rpcArgs[1])
-		targetSeed, err := strconv.ParseInt(rpcArgs[2], 10, 64)
+		targetSeed, err := strconv.Atoi(rpcArgs[2])
 		if err != nil {
 			panic(err)
 		}
diff --git a/main_test.go b/main_test.go
index 5ae76a8..f8c3e26 100644
--- a/main_test.go
+++ b/main_test.go
@@ -12,6 +12,8 @@ import (
 	// gologging "github.com/whyrusleeping/go-logging"
 )
 
+var nodeCount int
+
 func makeUnbootstrappedNode(t *testing.T, ctx context.Context, number int) *Node {
 	return makeTestingNode(t, ctx, number, false, nil)
 }
@@ -22,8 +24,12 @@ func makeTestingNode(
 	number int,
 	doBootstrapping bool,
 	bootstrapPeers []pstore.PeerInfo) *Node {
-	listeningPort := number + 10000
-	node, err := makeNode(ctx, listeningPort, int64(number), doBootstrapping, bootstrapPeers)
+	// FIXME:
+	//		1. Use 20000 to avoid conflitcs with the running nodes in the environment
+	//		2. Avoid reuse of listeningPort in the entire test, to avoid `dial error`s
+	listeningPort := 20000 + nodeCount
+	nodeCount++
+	node, err := makeNode(ctx, listeningPort, number, doBootstrapping, bootstrapPeers)
 	if err != nil {
 		t.Error("Failed to create node")
 	}
@@ -253,12 +259,12 @@ func TestRequestCollation(t *testing.T) {
 	defer cancel()
 	node0, node1 := makePeerNodes(t, ctx)
 	shardID := ShardIDType(1)
-	period := int64(42)
+	period := 42
 	collation, err := node0.requestCollation(ctx, node1.ID(), shardID, period, "2")
 	if err != nil {
 		t.Error("request collation failed")
 	}
-	if collation.ShardID != shardID || collation.Period != period {
+	if collation.ShardID != shardID || collation.Period != PBInt(period) {
 		t.Errorf(
 			"responded collation does not correspond to the request: collation.ShardID=%v, request.shardID=%v, collation.Period=%v, request.period=%v",
 			collation.ShardID,
diff --git a/node.go b/node.go
index 1e7649d..a6dc9e9 100644
--- a/node.go
+++ b/node.go
@@ -10,7 +10,7 @@ import (
 )
 
 // node client version
-const clientVersion = "go-p2p-node/0.0.1"
+const clientVersion = "sharding-p2p-node/0.0.1"
 
 // Node type - a p2p host implementing one or more p2p protocols
 type Node struct {
diff --git a/pb/rpc/rpc.pb.go b/pb/rpc/rpc.pb.go
index 2e27b59..287dabc 100644
--- a/pb/rpc/rpc.pb.go
+++ b/pb/rpc/rpc.pb.go
@@ -26,7 +26,7 @@ const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
 // AddPeer
 type RPCAddPeerReq struct {
 	Ip                   string   `protobuf:"bytes,1,opt,name=ip,proto3" json:"ip,omitempty"`
-	Port                 int32    `protobuf:"varint,2,opt,name=port,proto3" json:"port,omitempty"`
+	Port                 int64    `protobuf:"varint,2,opt,name=port,proto3" json:"port,omitempty"`
 	Seed                 int64    `protobuf:"varint,3,opt,name=seed,proto3" json:"seed,omitempty"`
 	XXX_NoUnkeyedLiteral struct{} `json:"-"`
 	XXX_unrecognized     []byte   `json:"-"`
@@ -37,7 +37,7 @@ func (m *RPCAddPeerReq) Reset()         { *m = RPCAddPeerReq{} }
 func (m *RPCAddPeerReq) String() string { return proto.CompactTextString(m) }
 func (*RPCAddPeerReq) ProtoMessage()    {}
 func (*RPCAddPeerReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_rpc_71a1ae02a48c7975, []int{0}
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{0}
 }
 func (m *RPCAddPeerReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RPCAddPeerReq.Unmarshal(m, b)
@@ -64,7 +64,7 @@ func (m *RPCAddPeerReq) GetIp() string {
 	return ""
 }
 
-func (m *RPCAddPeerReq) GetPort() int32 {
+func (m *RPCAddPeerReq) GetPort() int64 {
 	if m != nil {
 		return m.Port
 	}
@@ -90,7 +90,7 @@ func (m *RPCSubscribeShardReq) Reset()         { *m = RPCSubscribeShardReq{} }
 func (m *RPCSubscribeShardReq) String() string { return proto.CompactTextString(m) }
 func (*RPCSubscribeShardReq) ProtoMessage()    {}
 func (*RPCSubscribeShardReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_rpc_71a1ae02a48c7975, []int{1}
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{1}
 }
 func (m *RPCSubscribeShardReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RPCSubscribeShardReq.Unmarshal(m, b)
@@ -129,7 +129,7 @@ func (m *RPCUnsubscribeShardReq) Reset()         { *m = RPCUnsubscribeShardReq{}
 func (m *RPCUnsubscribeShardReq) String() string { return proto.CompactTextString(m) }
 func (*RPCUnsubscribeShardReq) ProtoMessage()    {}
 func (*RPCUnsubscribeShardReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_rpc_71a1ae02a48c7975, []int{2}
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{2}
 }
 func (m *RPCUnsubscribeShardReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RPCUnsubscribeShardReq.Unmarshal(m, b)
@@ -167,7 +167,7 @@ func (m *RPCGetSubscribedShardReq) Reset()         { *m = RPCGetSubscribedShardR
 func (m *RPCGetSubscribedShardReq) String() string { return proto.CompactTextString(m) }
 func (*RPCGetSubscribedShardReq) ProtoMessage()    {}
 func (*RPCGetSubscribedShardReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_rpc_71a1ae02a48c7975, []int{3}
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{3}
 }
 func (m *RPCGetSubscribedShardReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RPCGetSubscribedShardReq.Unmarshal(m, b)
@@ -199,7 +199,7 @@ func (m *RPCGetSubscribedShardReply) Reset()         { *m = RPCGetSubscribedShar
 func (m *RPCGetSubscribedShardReply) String() string { return proto.CompactTextString(m) }
 func (*RPCGetSubscribedShardReply) ProtoMessage()    {}
 func (*RPCGetSubscribedShardReply) Descriptor() ([]byte, []int) {
-	return fileDescriptor_rpc_71a1ae02a48c7975, []int{4}
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{4}
 }
 func (m *RPCGetSubscribedShardReply) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RPCGetSubscribedShardReply.Unmarshal(m, b)
@@ -236,9 +236,9 @@ func (m *RPCGetSubscribedShardReply) GetStatus() bool {
 // BroadcastCollation
 type RPCBroadcastCollationReq struct {
 	ShardID              int64    `protobuf:"varint,1,opt,name=shardID,proto3" json:"shardID,omitempty"`
-	Number               int32    `protobuf:"varint,2,opt,name=number,proto3" json:"number,omitempty"`
-	Size                 int32    `protobuf:"varint,3,opt,name=size,proto3" json:"size,omitempty"`
-	Period               int32    `protobuf:"varint,4,opt,name=period,proto3" json:"period,omitempty"`
+	Number               int64    `protobuf:"varint,2,opt,name=number,proto3" json:"number,omitempty"`
+	Size                 int64    `protobuf:"varint,3,opt,name=size,proto3" json:"size,omitempty"`
+	Period               int64    `protobuf:"varint,4,opt,name=period,proto3" json:"period,omitempty"`
 	XXX_NoUnkeyedLiteral struct{} `json:"-"`
 	XXX_unrecognized     []byte   `json:"-"`
 	XXX_sizecache        int32    `json:"-"`
@@ -248,7 +248,7 @@ func (m *RPCBroadcastCollationReq) Reset()         { *m = RPCBroadcastCollationR
 func (m *RPCBroadcastCollationReq) String() string { return proto.CompactTextString(m) }
 func (*RPCBroadcastCollationReq) ProtoMessage()    {}
 func (*RPCBroadcastCollationReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_rpc_71a1ae02a48c7975, []int{5}
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{5}
 }
 func (m *RPCBroadcastCollationReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RPCBroadcastCollationReq.Unmarshal(m, b)
@@ -275,21 +275,68 @@ func (m *RPCBroadcastCollationReq) GetShardID() int64 {
 	return 0
 }
 
-func (m *RPCBroadcastCollationReq) GetNumber() int32 {
+func (m *RPCBroadcastCollationReq) GetNumber() int64 {
 	if m != nil {
 		return m.Number
 	}
 	return 0
 }
 
-func (m *RPCBroadcastCollationReq) GetSize() int32 {
+func (m *RPCBroadcastCollationReq) GetSize() int64 {
 	if m != nil {
 		return m.Size
 	}
 	return 0
 }
 
-func (m *RPCBroadcastCollationReq) GetPeriod() int32 {
+func (m *RPCBroadcastCollationReq) GetPeriod() int64 {
+	if m != nil {
+		return m.Period
+	}
+	return 0
+}
+
+// RequestCollation
+type RPCRequestCollationReq struct {
+	ShardID              int64    `protobuf:"varint,1,opt,name=shardID,proto3" json:"shardID,omitempty"`
+	Period               int64    `protobuf:"varint,4,opt,name=period,proto3" json:"period,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *RPCRequestCollationReq) Reset()         { *m = RPCRequestCollationReq{} }
+func (m *RPCRequestCollationReq) String() string { return proto.CompactTextString(m) }
+func (*RPCRequestCollationReq) ProtoMessage()    {}
+func (*RPCRequestCollationReq) Descriptor() ([]byte, []int) {
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{6}
+}
+func (m *RPCRequestCollationReq) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_RPCRequestCollationReq.Unmarshal(m, b)
+}
+func (m *RPCRequestCollationReq) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_RPCRequestCollationReq.Marshal(b, m, deterministic)
+}
+func (dst *RPCRequestCollationReq) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_RPCRequestCollationReq.Merge(dst, src)
+}
+func (m *RPCRequestCollationReq) XXX_Size() int {
+	return xxx_messageInfo_RPCRequestCollationReq.Size(m)
+}
+func (m *RPCRequestCollationReq) XXX_DiscardUnknown() {
+	xxx_messageInfo_RPCRequestCollationReq.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_RPCRequestCollationReq proto.InternalMessageInfo
+
+func (m *RPCRequestCollationReq) GetShardID() int64 {
+	if m != nil {
+		return m.ShardID
+	}
+	return 0
+}
+
+func (m *RPCRequestCollationReq) GetPeriod() int64 {
 	if m != nil {
 		return m.Period
 	}
@@ -307,7 +354,7 @@ func (m *RPCStopServerReq) Reset()         { *m = RPCStopServerReq{} }
 func (m *RPCStopServerReq) String() string { return proto.CompactTextString(m) }
 func (*RPCStopServerReq) ProtoMessage()    {}
 func (*RPCStopServerReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_rpc_71a1ae02a48c7975, []int{6}
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{7}
 }
 func (m *RPCStopServerReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RPCStopServerReq.Unmarshal(m, b)
@@ -339,7 +386,7 @@ func (m *RPCReply) Reset()         { *m = RPCReply{} }
 func (m *RPCReply) String() string { return proto.CompactTextString(m) }
 func (*RPCReply) ProtoMessage()    {}
 func (*RPCReply) Descriptor() ([]byte, []int) {
-	return fileDescriptor_rpc_71a1ae02a48c7975, []int{7}
+	return fileDescriptor_rpc_5bc1ae5500c393c6, []int{8}
 }
 func (m *RPCReply) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RPCReply.Unmarshal(m, b)
@@ -380,6 +427,7 @@ func init() {
 	proto.RegisterType((*RPCGetSubscribedShardReq)(nil), "proto.rpc.RPCGetSubscribedShardReq")
 	proto.RegisterType((*RPCGetSubscribedShardReply)(nil), "proto.rpc.RPCGetSubscribedShardReply")
 	proto.RegisterType((*RPCBroadcastCollationReq)(nil), "proto.rpc.RPCBroadcastCollationReq")
+	proto.RegisterType((*RPCRequestCollationReq)(nil), "proto.rpc.RPCRequestCollationReq")
 	proto.RegisterType((*RPCStopServerReq)(nil), "proto.rpc.RPCStopServerReq")
 	proto.RegisterType((*RPCReply)(nil), "proto.rpc.RPCReply")
 }
@@ -623,34 +671,34 @@ var _Poc_serviceDesc = grpc.ServiceDesc{
 	Metadata: "rpc.proto",
 }
 
-func init() { proto.RegisterFile("rpc.proto", fileDescriptor_rpc_71a1ae02a48c7975) }
-
-var fileDescriptor_rpc_71a1ae02a48c7975 = []byte{
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-	0x00, 0x00,
+func init() { proto.RegisterFile("rpc.proto", fileDescriptor_rpc_5bc1ae5500c393c6) }
+
+var fileDescriptor_rpc_5bc1ae5500c393c6 = []byte{
+	// 410 bytes of a gzipped FileDescriptorProto
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+	0x37, 0xf7, 0x7d, 0x60, 0xa1, 0x38, 0x41, 0xa7, 0xb6, 0xaf, 0x76, 0x19, 0xea, 0x26, 0xb7, 0x06,
+	0xf9, 0xe4, 0xca, 0x23, 0xb6, 0xc9, 0x95, 0x47, 0x74, 0x5c, 0x85, 0xba, 0x94, 0x05, 0xbd, 0xa9,
+	0xb9, 0x35, 0x62, 0x9f, 0x7d, 0x3a, 0x02, 0x0f, 0x15, 0x5e, 0xe3, 0xdb, 0xab, 0x45, 0x60, 0xe6,
+	0xa6, 0x63, 0xa5, 0xda, 0xa0, 0xfe, 0xe1, 0x27, 0xcd, 0xde, 0xc0, 0xc4, 0xeb, 0xbb, 0x64, 0x28,
+	0x8c, 0x77, 0x68, 0x4c, 0xfa, 0x0d, 0x9b, 0xd1, 0x9f, 0xe0, 0x50, 0x2e, 0xab, 0xdf, 0x21, 0x84,
+	0x5c, 0xe6, 0xe4, 0x35, 0x8c, 0x9b, 0xf6, 0x10, 0x1a, 0xb7, 0xbd, 0x8a, 0x3b, 0xa5, 0x8a, 0x1e,
+	0x75, 0x4f, 0xbc, 0x27, 0x7b, 0x40, 0x3e, 0xc2, 0x5d, 0xb7, 0x30, 0xe4, 0x69, 0x97, 0x78, 0x51,
+	0xa7, 0x21, 0xa5, 0x2f, 0x30, 0x3b, 0xaf, 0x11, 0x79, 0xd6, 0xa5, 0xf6, 0xd4, 0x6c, 0x48, 0x2d,
+	0x03, 0x72, 0x59, 0x21, 0xf2, 0xbc, 0x4b, 0xee, 0x2d, 0x60, 0xf4, 0xe2, 0x7e, 0x52, 0xed, 0xc1,
+	0x81, 0x5c, 0x96, 0xea, 0xdc, 0xa3, 0xb7, 0x76, 0x43, 0xaf, 0x7e, 0x0b, 0xf0, 0x77, 0xc0, 0xe4,
+	0xc9, 0x59, 0x92, 0xff, 0x8e, 0x7e, 0x40, 0x21, 0xbb, 0xf5, 0xbb, 0x2f, 0xff, 0x04, 0x00, 0x00,
+	0xff, 0xff, 0xcc, 0xf1, 0x05, 0x94, 0x2b, 0x04, 0x00, 0x00,
 }
diff --git a/pb/rpc/rpc.proto b/pb/rpc/rpc.proto
index 51908b0..aad9cc0 100644
--- a/pb/rpc/rpc.proto
+++ b/pb/rpc/rpc.proto
@@ -15,7 +15,7 @@ service Poc {
 // AddPeer
 message RPCAddPeerReq {
   string ip = 1;
-  int32 port = 2;
+  int64 port = 2;
   int64 seed = 3;
 }
 
@@ -37,14 +37,20 @@ message RPCGetSubscribedShardReply {
 // BroadcastCollation
 message RPCBroadcastCollationReq {
   int64 shardID = 1;
-  int32 number = 2;
-  int32 size = 3;
-  int32 period = 4;
+  int64 number = 2;
+  int64 size = 3;
+  int64 period = 4;
+}
+// RequestCollation
+message RPCRequestCollationReq {
+  int64 shardID = 1;
+  int64 period = 4;
 }
 // StopServer
 message RPCStopServerReq {
 }
 
+
 message RPCReply {
   string message = 1;
   bool status = 2;
diff --git a/requests.go b/requests.go
index 0adfc43..38a7324 100644
--- a/requests.go
+++ b/requests.go
@@ -36,15 +36,15 @@ func NewRequestProtocol(node *Node) *RequestProtocol {
 
 func getCollation(
 	shardID ShardIDType,
-	period int64,
+	period int,
 	collationHash string) (*pbmsg.Collation, error) {
 	// FIXME: fake response for now. Shuld query from the saved data.
 	//	with
 	//    	case specifies `shardID`, `period`
 	//  and case specifies `collationHash`
 	return &pbmsg.Collation{
-		ShardID: shardID,
-		Period:  period,
+		ShardID: PBInt(shardID),
+		Period:  PBInt(period),
 		Blobs:   []byte{},
 	}, nil
 }
@@ -155,8 +155,8 @@ func (p *RequestProtocol) onCollationRequest(s inet.Stream) {
 	// FIXME: add checks
 	var collation *pbmsg.Collation
 	collation, err := getCollation(
-		data.GetShardID(),
-		data.GetPeriod(),
+		ShardIDType(data.GetShardID()),
+		int(data.GetPeriod()),
 		data.GetHash(),
 	)
 	var collationResp *pbmsg.CollationResponse
@@ -187,7 +187,7 @@ func (p *RequestProtocol) requestCollation(
 	ctx context.Context,
 	peerID peer.ID,
 	shardID ShardIDType,
-	period int64,
+	period int,
 	blobs string) (*pbmsg.Collation, error) {
 	s, err := p.node.NewStream(
 		ctx,
@@ -198,8 +198,8 @@ func (p *RequestProtocol) requestCollation(
 		return nil, fmt.Errorf("failed to open new stream %v", err)
 	}
 	req := &pbmsg.CollationRequest{
-		ShardID: shardID,
-		Period:  period,
+		ShardID: PBInt(shardID),
+		Period:  PBInt(period),
 	}
 	if !sendProtoMessage(req, s) {
 		return nil, fmt.Errorf("failed to send request")
diff --git a/rpcclient.go b/rpcclient.go
index beafc5f..f76133f 100644
--- a/rpcclient.go
+++ b/rpcclient.go
@@ -9,7 +9,7 @@ import (
 	"google.golang.org/grpc"
 )
 
-func callRPCAddPeer(rpcAddr string, ipAddr string, port int, seed int64) {
+func callRPCAddPeer(rpcAddr string, ipAddr string, port int, seed int) {
 	conn, err := grpc.Dial(rpcAddr, grpc.WithInsecure())
 	if err != nil {
 		log.Fatalf("did not connect: %v", err)
@@ -18,8 +18,8 @@ func callRPCAddPeer(rpcAddr string, ipAddr string, port int, seed int64) {
 	client := pbrpc.NewPocClient(conn)
 	addPeerReq := &pbrpc.RPCAddPeerReq{
 		Ip:   ipAddr,
-		Port: int32(port),
-		Seed: seed,
+		Port: PBInt(port),
+		Seed: PBInt(seed),
 	}
 	log.Printf("rpcclient:AddPeer: sending=%v", addPeerReq)
 	res, err := client.AddPeer(context.Background(), addPeerReq)
@@ -95,9 +95,9 @@ func callRPCBroadcastCollation(
 	client := pbrpc.NewPocClient(conn)
 	broadcastCollationReq := &pbrpc.RPCBroadcastCollationReq{
 		ShardID: shardID,
-		Number:  int32(numCollations),
-		Size:    int32(collationSize),
-		Period:  int32(period),
+		Number:  PBInt(numCollations),
+		Size:    PBInt(collationSize),
+		Period:  PBInt(period),
 	}
 	log.Printf("rpcclient:BroadcastCollation: sending=%v", broadcastCollationReq)
 	res, err := client.BroadcastCollation(context.Background(), broadcastCollationReq)
diff --git a/rpcserver.go b/rpcserver.go
index abe1fff..7651bfd 100644
--- a/rpcserver.go
+++ b/rpcserver.go
@@ -30,7 +30,7 @@ func (s *server) AddPeer(ctx context.Context, req *pbrpc.RPCAddPeerReq) (*pbrpc.
 	defer span.Finish()
 
 	log.Printf("rpcserver:AddPeer: receive=%v", req)
-	_, targetPID, err := makeKey(req.Seed)
+	_, targetPID, err := makeKey(int(req.Seed))
 	mAddr := fmt.Sprintf(
 		"/ip4/%s/tcp/%d/ipfs/%s",
 		req.Ip,
@@ -151,7 +151,7 @@ func (s *server) BroadcastCollation(
 		// TODO: catching error
 		s.node.broadcastCollation(
 			ShardIDType(shardID),
-			int64(i),
+			i,
 			randBytes,
 		)
 	}
diff --git a/shardmanager.go b/shardmanager.go
index ba7e2b3..02604d2 100644
--- a/shardmanager.go
+++ b/shardmanager.go
@@ -333,11 +333,11 @@ func (n *ShardManager) SubscribeShardCollations(shardID ShardIDType) {
 	n.shardCollationsSubs[shardID] = collationsSub
 }
 
-func (n *ShardManager) broadcastCollation(shardID ShardIDType, period int64, blobs []byte) bool {
+func (n *ShardManager) broadcastCollation(shardID ShardIDType, period int, blobs []byte) bool {
 	// create message data
 	data := &pbmsg.Collation{
 		ShardID: shardID,
-		Period:  period,
+		Period:  PBInt(period),
 		Blobs:   blobs,
 	}
 	return n.broadcastCollationMessage(data)