diff --git a/cmd/dev-server/main.go b/cmd/dev-server/main.go
index fc624f3..eca8062 100644
--- a/cmd/dev-server/main.go
+++ b/cmd/dev-server/main.go
@@ -1,10 +1,13 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"gitea.unprism.ru/KRBL/n9m"
+	"io"
 	"net"
 	"os"
+	"syscall"
 )
 
 func main() {
@@ -27,147 +30,139 @@ func main() {
 	}
 }
 
-func handle(conn net.Conn) {
-	var err error
-	var rn int
+func handleSpecialPackages(_ *n9m.SmartPackage, pack n9m.Package) error {
+	switch pack.SSRC {
+	case n9m.SpecialPayloadTypeGPS:
+		fmt.Printf("%+v\n", pack.GPS)
+		return nil
+	default:
+		return fmt.Errorf("unhandled special operation: %d", pack.SSRC)
+	}
+}
 
-	var serial string
+func handleCertificateConnect(sPack *n9m.SmartPackage, pack n9m.Package) (err error) {
+	var params n9m.CertificateConnectRequest
 
-	packS := n9m.Package{}
-	tmp := make([]byte, 1024)
+	if err = pack.GetParametersAs(&params); err != nil {
+		return fmt.Errorf("failed to get parameters: %w", err)
+	}
 
-	for {
-		rn, err = conn.Read(tmp)
+	var response = n9m.CertificateConnectResponse{
+		ErrorCode:   0,
+		CommandMask: n9m.CommandMaskAll,
+	}
 
-		if err != nil {
-			fmt.Println(err)
-			return
+	pack.SetResponse(response)
+
+	if _, err = sPack.Write(pack.PackPackage()); err != nil {
+		return fmt.Errorf("failed to write package: %w", err)
+	}
+
+	fmt.Println("Connected:", params.SerialNumber)
+	sPack.Storage["serial"] = params.SerialNumber
+
+	var request n9m.ConfigModelGetRequest
+	request.MDVR = "?"
+
+	pack.Payload.Module = "CONFIGMODEL"
+	pack.Payload.Operation = "GET"
+	pack.SetParameters(request)
+
+	sPack.Write(pack.PackPackage())
+
+	return
+}
+
+func handleKeepAlive(sPack *n9m.SmartPackage, pack n9m.Package) (err error) {
+	serial := sPack.Storage["serial"]
+	fmt.Println(serial, "still alive!")
+
+	pack.SetResponse(nil)
+	sPack.Write(pack.PackPackage())
+
+	return
+}
+
+func handleGetConfig(sPack *n9m.SmartPackage, pack n9m.Package) (err error) {
+	serial := sPack.Storage["serial"]
+
+	os.WriteFile(fmt.Sprintf("./%s.json", serial), pack.RawPayload, 0644)
+
+	return
+}
+
+func handleUselessAlarms(sPack *n9m.SmartPackage, pack n9m.Package, response n9m.SendAlarmInfoResponse) (err error) {
+	return nil
+}
+
+func handleVideoLossAlarm(sPack *n9m.SmartPackage, pack n9m.Package, response n9m.SendAlarmInfoResponse) (err error) {
+	fmt.Println("Video loss alarm!")
+	return nil
+}
+
+func handleCameraCoveredAlarm(sPack *n9m.SmartPackage, pack n9m.Package, response n9m.SendAlarmInfoResponse) (err error) {
+	fmt.Println("Camera covered alarm!")
+	return nil
+}
+
+func createSmartPackage(conn net.Conn) (pack *n9m.SmartPackage) {
+	pack = n9m.NewSmartPackage(conn)
+
+	pack.AddPayloadHandler(n9m.PayloadTypeSpecial, handleSpecialPackages)
+
+	pack.AddJSONHandler("CERTIFICATE", "CONNECT", handleCertificateConnect)
+	pack.AddJSONHandler("CERTIFICATE", "KEEPALIVE", handleKeepAlive)
+	pack.AddJSONHandler("CONFIGMODEL", "GET", handleGetConfig)
+
+	pack.AddAlarmHandler(n9m.AlarmTypeMotionDetection, handleUselessAlarms)
+
+	pack.AddAlarmHandler(n9m.AlarmTypeVideoLoss, handleVideoLossAlarm)
+	pack.AddAlarmHandler(n9m.AlarmTypeCameraCovered, handleCameraCoveredAlarm)
+
+	return
+}
+
+/*
+	go func() {
+		pack := packS
+		pack.Payload.Module = "EVEM"
+		pack.Payload.Operation = "GALARMING"
+
+		ticker := time.NewTicker(5 * time.Second)
+		defer ticker.Stop()
+
+		for range ticker.C {
+			fmt.Println("Sent!")
+			if _, err := conn.Write(pack.PackPackage()); err != nil {
+				fmt.Println("Failed to send GALARMING:", err)
+				return
+			}
 		}
+	}()
+*/
 
-		packS.AddToAccum(tmp[:rn])
+func isNetConnClosedErr(err error) bool {
+	switch {
+	case
+		errors.Is(err, net.ErrClosed),
+		errors.Is(err, io.EOF),
+		errors.Is(err, syscall.EPIPE):
+		return true
+	default:
+		return false
+	}
+}
 
-		for packS.ReadPackage() {
-			switch packS.PayloadType {
-			case n9m.PayloadTypeData:
-				combined := packS.Payload.Module + ":" + packS.Payload.Operation
+func handle(conn net.Conn) {
+	pack := createSmartPackage(conn)
 
-				switch combined {
-				case "CERTIFICATE:CONNECT":
-					var params n9m.CertificateConnectRequest
+	var err error
+	for {
+		if err = pack.Handle(); err != nil {
+			fmt.Println("Error:", err)
 
-					if err = packS.GetParametersAs(&params); err != nil {
-						fmt.Println(combined, err)
-						return
-					}
-
-					var response = n9m.CertificateConnectResponse{
-						ErrorCode:   0,
-						CommandMask: n9m.CommandMaskAll,
-					}
-
-					packS.SetResponse(response)
-
-					if _, err = conn.Write(packS.PackPackage()); err != nil {
-						fmt.Println(combined, err)
-						return
-					}
-
-					fmt.Println("Connected:", params.SerialNumber)
-					serial = params.SerialNumber
-
-					var request n9m.ConfigModelGetRequest
-					request.MDVR = "?"
-					packS.Payload.Module = "CONFIGMODEL"
-					packS.Payload.Operation = "GET"
-					packS.SetParameters(request)
-
-					conn.Write(packS.PackPackage())
-
-					/*
-						go func() {
-							pack := packS
-							pack.Payload.Module = "EVEM"
-							pack.Payload.Operation = "GALARMING"
-
-							ticker := time.NewTicker(5 * time.Second)
-							defer ticker.Stop()
-
-							for range ticker.C {
-								fmt.Println("Sent!")
-								if _, err := conn.Write(pack.PackPackage()); err != nil {
-									fmt.Println("Failed to send GALARMING:", err)
-									return
-								}
-							}
-						}()
-					*/
-				case "CERTIFICATE:KEEPALIVE":
-					packS.SetResponse(nil)
-					if _, err = conn.Write(packS.PackPackage()); err != nil {
-						fmt.Println(combined, err)
-						return
-					}
-
-					fmt.Println("Connection is still alive!")
-				case "EVEM:GGALARMING":
-					fmt.Println(string(packS.RawPayload))
-
-					var response n9m.EventModelGetAlarmingResponse
-					if err = packS.GetResponseAs(&response); err != nil {
-						fmt.Println(combined, err)
-						continue
-					}
-
-					fmt.Printf("%+v\n", response)
-				case "CONFIGMODEL:GET":
-					os.WriteFile(fmt.Sprintf("./%s.json", serial), packS.RawPayload, 0644)
-				case "EVEM:SENDALARMINFO":
-					var params n9m.SendAlarmInfoParameters
-					var response n9m.SendAlarmInfoResponse
-
-					if err = packS.GetParametersAs(&params); err != nil {
-						fmt.Printf("Error: %s\nData: %s", err, packS.RawPayload)
-						continue
-					}
-
-					response.ErrorCode = 0
-					response.AlarmType = params.AlarmType
-					response.CommandType = params.CommandType
-					response.AlarmUID = params.AlarmUID
-					response.NumberOfRestarts = params.NumberOfRestarts
-					response.InstructionSerial = params.InstructionSerial
-
-					switch params.AlarmType {
-					case n9m.AlarmTypeMotionDetection:
-						break
-					case n9m.AlarmTypeVideoLoss, n9m.AlarmTypeCameraCovered:
-						var cameraParams n9m.SendAlarmInfoCameraParameters
-
-						if err = packS.GetParametersAs(&cameraParams); err != nil {
-							fmt.Printf("Error: %s\nData: %s", err, packS.RawPayload)
-							continue
-						}
-
-						fmt.Printf("%+v\n", cameraParams)
-
-						packS.SetResponse(response)
-						conn.Write(packS.PackPackage())
-					default:
-						fmt.Println("Unknown alarm type:", params.AlarmType)
-					}
-				default:
-					fmt.Println("Strange operation:", combined)
-				}
-
-			case n9m.PayloadTypeSpecial:
-				switch packS.SSRC {
-				case n9m.SpecialPayloadTypeGPS:
-					fmt.Printf("%+v\n", packS.GPS)
-				default:
-					fmt.Println("Unhandled special operation:", packS.SSRC)
-				}
-			default:
-				fmt.Println("Unhandled operation:", packS.PayloadType)
+			if isNetConnClosedErr(err) {
+				return
 			}
 		}
 	}
diff --git a/scheme.go b/scheme.go
index 4f4922c..e82c72e 100644
--- a/scheme.go
+++ b/scheme.go
@@ -3,6 +3,7 @@ package n9m
 import (
 	"encoding/json"
 	"fmt"
+	"net"
 	"strconv"
 	"time"
 )
@@ -137,3 +138,18 @@ type Package struct {
 
 	Accum []byte
 }
+
+type ProcessFunc func(*SmartPackage, Package) error
+type AlarmProcessFunc func(*SmartPackage, Package, SendAlarmInfoResponse) error
+
+type SmartPackage struct {
+	pack Package
+
+	conn net.Conn
+	buff []byte
+
+	payloadProcess map[PayloadType]ProcessFunc
+	jsonProcess    map[string]ProcessFunc
+	alarmProcess   map[AlarmType]AlarmProcessFunc
+	Storage        map[string]interface{}
+}
diff --git a/smart.go b/smart.go
new file mode 100644
index 0000000..401880f
--- /dev/null
+++ b/smart.go
@@ -0,0 +1,124 @@
+package n9m
+
+import (
+	"fmt"
+	"net"
+)
+
+func NewSmartPackage(conn net.Conn) *SmartPackage {
+	return &SmartPackage{
+		pack:           Package{},
+		conn:           conn,
+		buff:           make([]byte, 1024),
+		payloadProcess: make(map[PayloadType]ProcessFunc),
+		jsonProcess:    make(map[string]ProcessFunc),
+		alarmProcess:   make(map[AlarmType]AlarmProcessFunc),
+		Storage:        make(map[string]interface{}),
+	}
+}
+
+func (pack *SmartPackage) AddPayloadHandler(payloadType PayloadType, processFunc ProcessFunc) {
+	pack.payloadProcess[payloadType] = processFunc
+}
+
+func (pack *SmartPackage) AddJSONHandler(module, operation string, processFunc ProcessFunc) {
+	pack.jsonProcess[fmt.Sprintf("%s:%s", module, operation)] = processFunc
+}
+
+func (pack *SmartPackage) AddAlarmHandler(alarmType AlarmType, processFunc AlarmProcessFunc) {
+	pack.alarmProcess[alarmType] = processFunc
+}
+
+func (pack *SmartPackage) handleAlarm() (err error) {
+	if !(pack.pack.PayloadType == PayloadTypeData && pack.pack.Payload.Module == "EVEM" && pack.pack.Payload.Operation == "SENDALARMINFO") {
+		return fmt.Errorf("invalid payload type or operation for alarm handling")
+	}
+
+	var params SendAlarmInfoParameters
+	if err = pack.pack.GetParametersAs(&params); err != nil {
+		return fmt.Errorf("invalid payload")
+	}
+
+	var processFunc AlarmProcessFunc
+	var ok bool
+	if processFunc, ok = pack.alarmProcess[params.AlarmType]; !ok {
+		return fmt.Errorf("unhanled alarm")
+	}
+
+	var response SendAlarmInfoResponse
+
+	response.ErrorCode = 0
+	response.AlarmType = params.AlarmType
+	response.CommandType = params.CommandType
+	response.AlarmUID = params.AlarmUID
+	response.NumberOfRestarts = params.NumberOfRestarts
+	response.InstructionSerial = params.InstructionSerial
+
+	return processFunc(pack, pack.pack, response)
+}
+
+func (pack *SmartPackage) handleJson() (err error) {
+	if pack.pack.PayloadType != PayloadTypeData {
+		return fmt.Errorf("invalid json payload type")
+	}
+
+	if err = pack.handleAlarm(); err == nil {
+		return
+	}
+
+	var processFunc ProcessFunc
+	var ok bool
+	if processFunc, ok = pack.jsonProcess[fmt.Sprintf("%s:%s", pack.pack.Payload.Module, pack.pack.Payload.Operation)]; !ok {
+		return fmt.Errorf("unhanled operation")
+	}
+
+	return processFunc(pack, pack.pack)
+}
+
+func (pack *SmartPackage) handle() (err error) {
+	if err = pack.handleJson(); err == nil {
+		return
+	}
+
+	var processFunc ProcessFunc
+	var ok bool
+	if processFunc, ok = pack.payloadProcess[pack.pack.PayloadType]; !ok {
+		return fmt.Errorf("unhanled payload type")
+	}
+
+	return processFunc(pack, pack.pack)
+}
+
+func (pack *SmartPackage) handleLoop() (err error) {
+	for pack.pack.ReadPackage() {
+		if err = pack.handle(); err != nil {
+			return err
+		}
+	}
+
+	return
+}
+
+func (pack *SmartPackage) Handle() (err error) {
+	if err = pack.handleLoop(); err != nil {
+		return err
+	}
+
+	var rn int
+
+	if rn, err = pack.conn.Read(pack.buff); err != nil {
+		return
+	}
+
+	pack.pack.AddToAccum(pack.buff[:rn])
+
+	return pack.handleLoop()
+}
+
+func (pack *SmartPackage) GetPackage() Package {
+	return pack.pack
+}
+
+func (pack *SmartPackage) Write(data []byte) (int, error) {
+	return pack.conn.Write(data)
+}