diff --git a/pkg/authReg/handler.go b/pkg/authReg/handler.go
new file mode 100644
index 0000000..735525b
--- /dev/null
+++ b/pkg/authReg/handler.go
@@ -0,0 +1,40 @@
+package authReg
+
+import (
+	log "github.com/sirupsen/logrus"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+	er "merch-api/pkg/externalRegistration/v1"
+	"time"
+)
+
+const pkgLogHeader string = "External service registration |"
+
+type Handler struct {
+	client er.ExternalRegistrationClient
+	*service
+}
+
+type Deps struct {
+	Addr    string
+	Timeout time.Duration
+}
+
+func New(deps Deps) *Handler {
+	var opts []grpc.DialOption
+	insec := grpc.WithTransportCredentials(insecure.NewCredentials())
+	opts = append(opts, insec)
+
+	conn, err := grpc.NewClient(deps.Addr, opts...)
+	if err != nil {
+		log.WithError(err).Fatalf("%v grpc connection failed", pkgLogHeader)
+	}
+
+	client := er.NewExternalRegistrationClient(conn)
+	log.WithField("address", deps.Addr).Debugf("%v client", pkgLogHeader)
+
+	return &Handler{
+		client:  client,
+		service: newService(client, deps.Timeout),
+	}
+}
diff --git a/pkg/authReg/interface.go b/pkg/authReg/interface.go
new file mode 100644
index 0000000..f75f126
--- /dev/null
+++ b/pkg/authReg/interface.go
@@ -0,0 +1,9 @@
+package authReg
+
+import (
+	"context"
+)
+
+type ServiceRegistrar interface {
+	AuthenticateOrRegister(ctx context.Context, req *RegRequest) (*RegResponse, error)
+}
diff --git a/pkg/authReg/service.go b/pkg/authReg/service.go
new file mode 100644
index 0000000..5b1a6b7
--- /dev/null
+++ b/pkg/authReg/service.go
@@ -0,0 +1,43 @@
+package authReg
+
+import (
+	"context"
+	er "merch-api/pkg/externalRegistration/v1"
+	"time"
+)
+
+type service struct {
+	client  er.ExternalRegistrationClient
+	timeout time.Duration
+}
+
+func newService(c er.ExternalRegistrationClient, timeout time.Duration) *service {
+	return &service{
+		client:  c,
+		timeout: timeout,
+	}
+}
+
+func (s *service) AuthenticateOrRegister(ctx context.Context, req *RegRequest) (*RegResponse, error) {
+	authCtx, cancel := context.WithTimeout(ctx, s.timeout)
+	defer cancel()
+
+	request := er.RegistrationRequest{
+		Name:           req.Name,
+		Description:    req.Description,
+		ServiceCode:    int32(req.BaseCode),
+		ServiceEndCode: int32(req.EndCode),
+		Secret:         req.SecretHash,
+		Status:         req.Status,
+	}
+
+	response, err := s.client.AuthenticateOrRegister(authCtx, &request)
+	if err != nil {
+		return nil, err
+	}
+
+	return &RegResponse{
+		ServiceId:         response.ServiceId,
+		AlreadyRegistered: response.AlreadyRegistered,
+	}, nil
+}
diff --git a/pkg/authReg/struct.go b/pkg/authReg/struct.go
new file mode 100644
index 0000000..f10b89a
--- /dev/null
+++ b/pkg/authReg/struct.go
@@ -0,0 +1,15 @@
+package authReg
+
+type RegRequest struct {
+	Name        string
+	Description string
+	BaseCode    int
+	EndCode     int
+	SecretHash  string
+	Status      string
+}
+
+type RegResponse struct {
+	ServiceId         int32
+	AlreadyRegistered bool
+}
diff --git a/pkg/externalRegistration/v1/serviceRegistration.pb.go b/pkg/externalRegistration/v1/serviceRegistration.pb.go
new file mode 100644
index 0000000..9f1da73
--- /dev/null
+++ b/pkg/externalRegistration/v1/serviceRegistration.pb.go
@@ -0,0 +1,228 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.36.8
+// 	protoc        v6.33.1
+// source: proto/serviceRegistration.proto
+
+package externalRegV1
+
+import (
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+	unsafe "unsafe"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+type RegistrationRequest struct {
+	state          protoimpl.MessageState `protogen:"open.v1"`
+	Name           string                 `protobuf:"bytes,1,opt,name=name,proto3" json:"name,omitempty"`
+	Description    string                 `protobuf:"bytes,2,opt,name=description,proto3" json:"description,omitempty"`
+	ServiceCode    int32                  `protobuf:"varint,3,opt,name=service_code,json=serviceCode,proto3" json:"service_code,omitempty"`
+	ServiceEndCode int32                  `protobuf:"varint,4,opt,name=service_end_code,json=serviceEndCode,proto3" json:"service_end_code,omitempty"`
+	Secret         string                 `protobuf:"bytes,5,opt,name=secret,proto3" json:"secret,omitempty"`
+	Status         string                 `protobuf:"bytes,6,opt,name=status,proto3" json:"status,omitempty"`
+	unknownFields  protoimpl.UnknownFields
+	sizeCache      protoimpl.SizeCache
+}
+
+func (x *RegistrationRequest) Reset() {
+	*x = RegistrationRequest{}
+	mi := &file_proto_serviceRegistration_proto_msgTypes[0]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *RegistrationRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*RegistrationRequest) ProtoMessage() {}
+
+func (x *RegistrationRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_serviceRegistration_proto_msgTypes[0]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use RegistrationRequest.ProtoReflect.Descriptor instead.
+func (*RegistrationRequest) Descriptor() ([]byte, []int) {
+	return file_proto_serviceRegistration_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *RegistrationRequest) GetName() string {
+	if x != nil {
+		return x.Name
+	}
+	return ""
+}
+
+func (x *RegistrationRequest) GetDescription() string {
+	if x != nil {
+		return x.Description
+	}
+	return ""
+}
+
+func (x *RegistrationRequest) GetServiceCode() int32 {
+	if x != nil {
+		return x.ServiceCode
+	}
+	return 0
+}
+
+func (x *RegistrationRequest) GetServiceEndCode() int32 {
+	if x != nil {
+		return x.ServiceEndCode
+	}
+	return 0
+}
+
+func (x *RegistrationRequest) GetSecret() string {
+	if x != nil {
+		return x.Secret
+	}
+	return ""
+}
+
+func (x *RegistrationRequest) GetStatus() string {
+	if x != nil {
+		return x.Status
+	}
+	return ""
+}
+
+type RegistrationResponse struct {
+	state             protoimpl.MessageState `protogen:"open.v1"`
+	ServiceId         int32                  `protobuf:"varint,1,opt,name=service_id,json=serviceId,proto3" json:"service_id,omitempty"`
+	AlreadyRegistered bool                   `protobuf:"varint,2,opt,name=already_registered,json=alreadyRegistered,proto3" json:"already_registered,omitempty"`
+	unknownFields     protoimpl.UnknownFields
+	sizeCache         protoimpl.SizeCache
+}
+
+func (x *RegistrationResponse) Reset() {
+	*x = RegistrationResponse{}
+	mi := &file_proto_serviceRegistration_proto_msgTypes[1]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *RegistrationResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*RegistrationResponse) ProtoMessage() {}
+
+func (x *RegistrationResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_serviceRegistration_proto_msgTypes[1]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use RegistrationResponse.ProtoReflect.Descriptor instead.
+func (*RegistrationResponse) Descriptor() ([]byte, []int) {
+	return file_proto_serviceRegistration_proto_rawDescGZIP(), []int{1}
+}
+
+func (x *RegistrationResponse) GetServiceId() int32 {
+	if x != nil {
+		return x.ServiceId
+	}
+	return 0
+}
+
+func (x *RegistrationResponse) GetAlreadyRegistered() bool {
+	if x != nil {
+		return x.AlreadyRegistered
+	}
+	return false
+}
+
+var File_proto_serviceRegistration_proto protoreflect.FileDescriptor
+
+const file_proto_serviceRegistration_proto_rawDesc = "" +
+	"\n" +
+	"\x1fproto/serviceRegistration.proto\x12\x11auth.registration\"\xc8\x01\n" +
+	"\x13RegistrationRequest\x12\x12\n" +
+	"\x04name\x18\x01 \x01(\tR\x04name\x12 \n" +
+	"\vdescription\x18\x02 \x01(\tR\vdescription\x12!\n" +
+	"\fservice_code\x18\x03 \x01(\x05R\vserviceCode\x12(\n" +
+	"\x10service_end_code\x18\x04 \x01(\x05R\x0eserviceEndCode\x12\x16\n" +
+	"\x06secret\x18\x05 \x01(\tR\x06secret\x12\x16\n" +
+	"\x06status\x18\x06 \x01(\tR\x06status\"d\n" +
+	"\x14RegistrationResponse\x12\x1d\n" +
+	"\n" +
+	"service_id\x18\x01 \x01(\x05R\tserviceId\x12-\n" +
+	"\x12already_registered\x18\x02 \x01(\bR\x11alreadyRegistered2\x81\x01\n" +
+	"\x14ExternalRegistration\x12i\n" +
+	"\x16AuthenticateOrRegister\x12&.auth.registration.RegistrationRequest\x1a'.auth.registration.RegistrationResponseB,Z*/pkg/externalRegistration/v1;externalRegV1b\x06proto3"
+
+var (
+	file_proto_serviceRegistration_proto_rawDescOnce sync.Once
+	file_proto_serviceRegistration_proto_rawDescData []byte
+)
+
+func file_proto_serviceRegistration_proto_rawDescGZIP() []byte {
+	file_proto_serviceRegistration_proto_rawDescOnce.Do(func() {
+		file_proto_serviceRegistration_proto_rawDescData = protoimpl.X.CompressGZIP(unsafe.Slice(unsafe.StringData(file_proto_serviceRegistration_proto_rawDesc), len(file_proto_serviceRegistration_proto_rawDesc)))
+	})
+	return file_proto_serviceRegistration_proto_rawDescData
+}
+
+var file_proto_serviceRegistration_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
+var file_proto_serviceRegistration_proto_goTypes = []any{
+	(*RegistrationRequest)(nil),  // 0: auth.registration.RegistrationRequest
+	(*RegistrationResponse)(nil), // 1: auth.registration.RegistrationResponse
+}
+var file_proto_serviceRegistration_proto_depIdxs = []int32{
+	0, // 0: auth.registration.ExternalRegistration.AuthenticateOrRegister:input_type -> auth.registration.RegistrationRequest
+	1, // 1: auth.registration.ExternalRegistration.AuthenticateOrRegister:output_type -> auth.registration.RegistrationResponse
+	1, // [1:2] is the sub-list for method output_type
+	0, // [0:1] is the sub-list for method input_type
+	0, // [0:0] is the sub-list for extension type_name
+	0, // [0:0] is the sub-list for extension extendee
+	0, // [0:0] is the sub-list for field type_name
+}
+
+func init() { file_proto_serviceRegistration_proto_init() }
+func file_proto_serviceRegistration_proto_init() {
+	if File_proto_serviceRegistration_proto != nil {
+		return
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: unsafe.Slice(unsafe.StringData(file_proto_serviceRegistration_proto_rawDesc), len(file_proto_serviceRegistration_proto_rawDesc)),
+			NumEnums:      0,
+			NumMessages:   2,
+			NumExtensions: 0,
+			NumServices:   1,
+		},
+		GoTypes:           file_proto_serviceRegistration_proto_goTypes,
+		DependencyIndexes: file_proto_serviceRegistration_proto_depIdxs,
+		MessageInfos:      file_proto_serviceRegistration_proto_msgTypes,
+	}.Build()
+	File_proto_serviceRegistration_proto = out.File
+	file_proto_serviceRegistration_proto_goTypes = nil
+	file_proto_serviceRegistration_proto_depIdxs = nil
+}
diff --git a/pkg/externalRegistration/v1/serviceRegistration_grpc.pb.go b/pkg/externalRegistration/v1/serviceRegistration_grpc.pb.go
new file mode 100644
index 0000000..d516302
--- /dev/null
+++ b/pkg/externalRegistration/v1/serviceRegistration_grpc.pb.go
@@ -0,0 +1,121 @@
+// Code generated by protoc-gen-go-grpc. DO NOT EDIT.
+// versions:
+// - protoc-gen-go-grpc v1.5.1
+// - protoc             v6.33.1
+// source: proto/serviceRegistration.proto
+
+package externalRegV1
+
+import (
+	context "context"
+	grpc "google.golang.org/grpc"
+	codes "google.golang.org/grpc/codes"
+	status "google.golang.org/grpc/status"
+)
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+// Requires gRPC-Go v1.64.0 or later.
+const _ = grpc.SupportPackageIsVersion9
+
+const (
+	ExternalRegistration_AuthenticateOrRegister_FullMethodName = "/auth.registration.ExternalRegistration/AuthenticateOrRegister"
+)
+
+// ExternalRegistrationClient is the client API for ExternalRegistration service.
+//
+// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream.
+type ExternalRegistrationClient interface {
+	AuthenticateOrRegister(ctx context.Context, in *RegistrationRequest, opts ...grpc.CallOption) (*RegistrationResponse, error)
+}
+
+type externalRegistrationClient struct {
+	cc grpc.ClientConnInterface
+}
+
+func NewExternalRegistrationClient(cc grpc.ClientConnInterface) ExternalRegistrationClient {
+	return &externalRegistrationClient{cc}
+}
+
+func (c *externalRegistrationClient) AuthenticateOrRegister(ctx context.Context, in *RegistrationRequest, opts ...grpc.CallOption) (*RegistrationResponse, error) {
+	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
+	out := new(RegistrationResponse)
+	err := c.cc.Invoke(ctx, ExternalRegistration_AuthenticateOrRegister_FullMethodName, in, out, cOpts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+// ExternalRegistrationServer is the server API for ExternalRegistration service.
+// All implementations must embed UnimplementedExternalRegistrationServer
+// for forward compatibility.
+type ExternalRegistrationServer interface {
+	AuthenticateOrRegister(context.Context, *RegistrationRequest) (*RegistrationResponse, error)
+	mustEmbedUnimplementedExternalRegistrationServer()
+}
+
+// UnimplementedExternalRegistrationServer must be embedded to have
+// forward compatible implementations.
+//
+// NOTE: this should be embedded by value instead of pointer to avoid a nil
+// pointer dereference when methods are called.
+type UnimplementedExternalRegistrationServer struct{}
+
+func (UnimplementedExternalRegistrationServer) AuthenticateOrRegister(context.Context, *RegistrationRequest) (*RegistrationResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method AuthenticateOrRegister not implemented")
+}
+func (UnimplementedExternalRegistrationServer) mustEmbedUnimplementedExternalRegistrationServer() {}
+func (UnimplementedExternalRegistrationServer) testEmbeddedByValue()                              {}
+
+// UnsafeExternalRegistrationServer may be embedded to opt out of forward compatibility for this service.
+// Use of this interface is not recommended, as added methods to ExternalRegistrationServer will
+// result in compilation errors.
+type UnsafeExternalRegistrationServer interface {
+	mustEmbedUnimplementedExternalRegistrationServer()
+}
+
+func RegisterExternalRegistrationServer(s grpc.ServiceRegistrar, srv ExternalRegistrationServer) {
+	// If the following call pancis, it indicates UnimplementedExternalRegistrationServer was
+	// embedded by pointer and is nil.  This will cause panics if an
+	// unimplemented method is ever invoked, so we test this at initialization
+	// time to prevent it from happening at runtime later due to I/O.
+	if t, ok := srv.(interface{ testEmbeddedByValue() }); ok {
+		t.testEmbeddedByValue()
+	}
+	s.RegisterService(&ExternalRegistration_ServiceDesc, srv)
+}
+
+func _ExternalRegistration_AuthenticateOrRegister_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(RegistrationRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(ExternalRegistrationServer).AuthenticateOrRegister(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: ExternalRegistration_AuthenticateOrRegister_FullMethodName,
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(ExternalRegistrationServer).AuthenticateOrRegister(ctx, req.(*RegistrationRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
+// ExternalRegistration_ServiceDesc is the grpc.ServiceDesc for ExternalRegistration service.
+// It's only intended for direct use with grpc.RegisterService,
+// and not to be introspected or modified (even as a copy)
+var ExternalRegistration_ServiceDesc = grpc.ServiceDesc{
+	ServiceName: "auth.registration.ExternalRegistration",
+	HandlerType: (*ExternalRegistrationServer)(nil),
+	Methods: []grpc.MethodDesc{
+		{
+			MethodName: "AuthenticateOrRegister",
+			Handler:    _ExternalRegistration_AuthenticateOrRegister_Handler,
+		},
+	},
+	Streams:  []grpc.StreamDesc{},
+	Metadata: "proto/serviceRegistration.proto",
+}
diff --git a/proto/serviceRegistration.proto b/proto/serviceRegistration.proto
new file mode 100644
index 0000000..1228ea8
--- /dev/null
+++ b/proto/serviceRegistration.proto
@@ -0,0 +1,22 @@
+syntax = "proto3";
+
+package auth.registration;
+option go_package = "/pkg/externalRegistration/v1;externalRegV1";
+
+message RegistrationRequest {
+  string name = 1;
+  string description = 2;
+  int32 service_code = 3;
+  int32 service_end_code = 4;
+  string secret = 5;
+  string status = 6;
+}
+
+message RegistrationResponse {
+  int32 service_id = 1;
+  bool already_registered = 2;
+}
+
+service ExternalRegistration {
+  rpc AuthenticateOrRegister (RegistrationRequest) returns (RegistrationResponse);
+}
\ No newline at end of file