diff --git a/apps/sdlan/include/sdlan.hrl b/apps/sdlan/include/sdlan.hrl
index 89e43b1..c42021d 100644
--- a/apps/sdlan/include/sdlan.hrl
+++ b/apps/sdlan/include/sdlan.hrl
@@ -16,7 +16,6 @@
 -define(PACKET_EMPTY, 16#00).
 -define(PACKET_REGISTER_SUPER, 16#01).
 -define(PACKET_REGISTER_SUPER_ACK, 16#02).
--define(PACKET_REGISTER_SUPER_ACKNOWLEDGE, 16#03).
 -define(PACKET_REGISTER_SUPER_NAK, 16#04).
 -define(PACKET_UNREGISTER, 16#05).
 
@@ -24,10 +23,6 @@
 -define(PACKET_QUERY_INFO, 16#06).
 -define(PACKET_PEER_INFO, 16#07).
 
-%% 心跳机制
--define(PACKET_PING, 16#08).
--define(PACKET_PONG, 16#09).
-
 %% 推送的事件信息, 不需要返回值
 -define(PACKET_EVENT, 16#10).
 
@@ -41,17 +36,6 @@
 %% 网络关闭
 -define(PACKET_EVENT_NETWORK_SHUTDOWN, 16#FF).
 
-%% 推送命令信息, 需要等待返回值
--define(PACKET_COMMAND, 16#11).
--define(PACKET_COMMAND_ACK, 16#12).
-
-%% 网络发生变化
--define(PACKET_COMMAND_CHANGE_NETWORK, 16#01).
--define(PACKET_COMMAND_UPGRADE, 16#02).
-
-%% 网络流量统计
--define(PACKET_FLOW_TRACER, 16#15).
-
 -define(PACKET_REGISTER, 16#20).
 -define(PACKET_REGISTER_ACK, 16#21).
 
diff --git a/apps/sdlan/include/sdlan_pb.hrl b/apps/sdlan/include/sdlan_pb.hrl
index 92b4af8..84d7f80 100644
--- a/apps/sdlan/include/sdlan_pb.hrl
+++ b/apps/sdlan/include/sdlan_pb.hrl
@@ -25,6 +25,13 @@
         }).
 -endif.
 
+-ifndef('SDL_EMPTY_PB_H').
+-define('SDL_EMPTY_PB_H', true).
+-record(sdl_empty,
+        {pkt_id = 0             :: non_neg_integer() | undefined % = 1, optional, 32 bits
+        }).
+-endif.
+
 -ifndef('SDL_REGISTER_SUPER_PB_H').
 -define('SDL_REGISTER_SUPER_PB_H', true).
 -record(sdl_register_super,
diff --git a/apps/sdlan/src/sdlan_pb.erl b/apps/sdlan/src/sdlan_pb.erl
index a5ca60c..00dca84 100644
--- a/apps/sdlan/src/sdlan_pb.erl
+++ b/apps/sdlan/src/sdlan_pb.erl
@@ -59,6 +59,8 @@
 
 -type sdl_v6_info() :: #sdl_v6_info{}.
 
+-type sdl_empty() :: #sdl_empty{}.
+
 -type sdl_register_super() :: #sdl_register_super{}.
 
 -type sdl_register_super_ack() :: #sdl_register_super_ack{}.
@@ -97,9 +99,9 @@
 
 -type sdl_arp_response() :: #sdl_arp_response{}.
 
--export_type(['sdl_v4_info'/0, 'sdl_v6_info'/0, 'sdl_register_super'/0, 'sdl_register_super_ack'/0, 'sdl_register_super_nak'/0, 'sdl_query_info'/0, 'sdl_peer_info'/0, 'sdl_empty_peer_info'/0, 'sdl_nat_changed_event'/0, 'sdl_drop_macs_event'/0, 'sdl_refresh_auth_event'/0, 'sdl_send_register_event'/0, 'sdl_network_shutdown_event'/0, 'sdl_stun_request'/0, 'sdl_data'/0, 'sdl_register'/0, 'sdl_register_ack'/0, 'sdl_stun_probe'/0, 'sdl_stun_probe_reply'/0, 'sdl_arp_request'/0, 'sdl_arp_response'/0]).
--type '$msg_name'() :: sdl_v4_info | sdl_v6_info | sdl_register_super | sdl_register_super_ack | sdl_register_super_nak | sdl_query_info | sdl_peer_info | sdl_empty_peer_info | sdl_nat_changed_event | sdl_drop_macs_event | sdl_refresh_auth_event | sdl_send_register_event | sdl_network_shutdown_event | sdl_stun_request | sdl_data | sdl_register | sdl_register_ack | sdl_stun_probe | sdl_stun_probe_reply | sdl_arp_request | sdl_arp_response.
--type '$msg'() :: sdl_v4_info() | sdl_v6_info() | sdl_register_super() | sdl_register_super_ack() | sdl_register_super_nak() | sdl_query_info() | sdl_peer_info() | sdl_empty_peer_info() | sdl_nat_changed_event() | sdl_drop_macs_event() | sdl_refresh_auth_event() | sdl_send_register_event() | sdl_network_shutdown_event() | sdl_stun_request() | sdl_data() | sdl_register() | sdl_register_ack() | sdl_stun_probe() | sdl_stun_probe_reply() | sdl_arp_request() | sdl_arp_response().
+-export_type(['sdl_v4_info'/0, 'sdl_v6_info'/0, 'sdl_empty'/0, 'sdl_register_super'/0, 'sdl_register_super_ack'/0, 'sdl_register_super_nak'/0, 'sdl_query_info'/0, 'sdl_peer_info'/0, 'sdl_empty_peer_info'/0, 'sdl_nat_changed_event'/0, 'sdl_drop_macs_event'/0, 'sdl_refresh_auth_event'/0, 'sdl_send_register_event'/0, 'sdl_network_shutdown_event'/0, 'sdl_stun_request'/0, 'sdl_data'/0, 'sdl_register'/0, 'sdl_register_ack'/0, 'sdl_stun_probe'/0, 'sdl_stun_probe_reply'/0, 'sdl_arp_request'/0, 'sdl_arp_response'/0]).
+-type '$msg_name'() :: sdl_v4_info | sdl_v6_info | sdl_empty | sdl_register_super | sdl_register_super_ack | sdl_register_super_nak | sdl_query_info | sdl_peer_info | sdl_empty_peer_info | sdl_nat_changed_event | sdl_drop_macs_event | sdl_refresh_auth_event | sdl_send_register_event | sdl_network_shutdown_event | sdl_stun_request | sdl_data | sdl_register | sdl_register_ack | sdl_stun_probe | sdl_stun_probe_reply | sdl_arp_request | sdl_arp_response.
+-type '$msg'() :: sdl_v4_info() | sdl_v6_info() | sdl_empty() | sdl_register_super() | sdl_register_super_ack() | sdl_register_super_nak() | sdl_query_info() | sdl_peer_info() | sdl_empty_peer_info() | sdl_nat_changed_event() | sdl_drop_macs_event() | sdl_refresh_auth_event() | sdl_send_register_event() | sdl_network_shutdown_event() | sdl_stun_request() | sdl_data() | sdl_register() | sdl_register_ack() | sdl_stun_probe() | sdl_stun_probe_reply() | sdl_arp_request() | sdl_arp_response().
 -export_type(['$msg_name'/0, '$msg'/0]).
 
 -if(?OTP_RELEASE >= 24).
@@ -128,6 +130,7 @@ encode_msg(Msg, MsgName, Opts) ->
     case MsgName of
         sdl_v4_info -> encode_msg_sdl_v4_info(id(Msg, TrUserData), TrUserData);
         sdl_v6_info -> encode_msg_sdl_v6_info(id(Msg, TrUserData), TrUserData);
+        sdl_empty -> encode_msg_sdl_empty(id(Msg, TrUserData), TrUserData);
         sdl_register_super -> encode_msg_sdl_register_super(id(Msg, TrUserData), TrUserData);
         sdl_register_super_ack -> encode_msg_sdl_register_super_ack(id(Msg, TrUserData), TrUserData);
         sdl_register_super_nak -> encode_msg_sdl_register_super_nak(id(Msg, TrUserData), TrUserData);
@@ -207,6 +210,20 @@ encode_msg_sdl_v6_info(#sdl_v6_info{port = F1, v6 = F2}, Bin, TrUserData) ->
            end
     end.
 
+encode_msg_sdl_empty(Msg, TrUserData) -> encode_msg_sdl_empty(Msg, <<>>, TrUserData).
+
+
+encode_msg_sdl_empty(#sdl_empty{pkt_id = F1}, Bin, TrUserData) ->
+    if F1 == undefined -> Bin;
+       true ->
+           begin
+               TrF1 = id(F1, TrUserData),
+               if TrF1 =:= 0 -> Bin;
+                  true -> e_varint(TrF1, <<Bin/binary, 8>>, TrUserData)
+               end
+           end
+    end.
+
 encode_msg_sdl_register_super(Msg, TrUserData) -> encode_msg_sdl_register_super(Msg, <<>>, TrUserData).
 
 
@@ -1160,6 +1177,7 @@ decode_msg_1_catch(Bin, MsgName, TrUserData) ->
 
 decode_msg_2_doit(sdl_v4_info, Bin, TrUserData) -> id(decode_msg_sdl_v4_info(Bin, TrUserData), TrUserData);
 decode_msg_2_doit(sdl_v6_info, Bin, TrUserData) -> id(decode_msg_sdl_v6_info(Bin, TrUserData), TrUserData);
+decode_msg_2_doit(sdl_empty, Bin, TrUserData) -> id(decode_msg_sdl_empty(Bin, TrUserData), TrUserData);
 decode_msg_2_doit(sdl_register_super, Bin, TrUserData) -> id(decode_msg_sdl_register_super(Bin, TrUserData), TrUserData);
 decode_msg_2_doit(sdl_register_super_ack, Bin, TrUserData) -> id(decode_msg_sdl_register_super_ack(Bin, TrUserData), TrUserData);
 decode_msg_2_doit(sdl_register_super_nak, Bin, TrUserData) -> id(decode_msg_sdl_register_super_nak(Bin, TrUserData), TrUserData);
@@ -1291,6 +1309,50 @@ skip_32_sdl_v6_info(<<_:32, Rest/binary>>, Z1, Z2, F, F@_1, F@_2, TrUserData) ->
 
 skip_64_sdl_v6_info(<<_:64, Rest/binary>>, Z1, Z2, F, F@_1, F@_2, TrUserData) -> dfp_read_field_def_sdl_v6_info(Rest, Z1, Z2, F, F@_1, F@_2, TrUserData).
 
+decode_msg_sdl_empty(Bin, TrUserData) -> dfp_read_field_def_sdl_empty(Bin, 0, 0, 0, id(0, TrUserData), TrUserData).
+
+dfp_read_field_def_sdl_empty(<<8, Rest/binary>>, Z1, Z2, F, F@_1, TrUserData) -> d_field_sdl_empty_pkt_id(Rest, Z1, Z2, F, F@_1, TrUserData);
+dfp_read_field_def_sdl_empty(<<>>, 0, 0, _, F@_1, _) -> #sdl_empty{pkt_id = F@_1};
+dfp_read_field_def_sdl_empty(Other, Z1, Z2, F, F@_1, TrUserData) -> dg_read_field_def_sdl_empty(Other, Z1, Z2, F, F@_1, TrUserData).
+
+dg_read_field_def_sdl_empty(<<1:1, X:7, Rest/binary>>, N, Acc, F, F@_1, TrUserData) when N < 32 - 7 -> dg_read_field_def_sdl_empty(Rest, N + 7, X bsl N + Acc, F, F@_1, TrUserData);
+dg_read_field_def_sdl_empty(<<0:1, X:7, Rest/binary>>, N, Acc, _, F@_1, TrUserData) ->
+    Key = X bsl N + Acc,
+    case Key of
+        8 -> d_field_sdl_empty_pkt_id(Rest, 0, 0, 0, F@_1, TrUserData);
+        _ ->
+            case Key band 7 of
+                0 -> skip_varint_sdl_empty(Rest, 0, 0, Key bsr 3, F@_1, TrUserData);
+                1 -> skip_64_sdl_empty(Rest, 0, 0, Key bsr 3, F@_1, TrUserData);
+                2 -> skip_length_delimited_sdl_empty(Rest, 0, 0, Key bsr 3, F@_1, TrUserData);
+                3 -> skip_group_sdl_empty(Rest, 0, 0, Key bsr 3, F@_1, TrUserData);
+                5 -> skip_32_sdl_empty(Rest, 0, 0, Key bsr 3, F@_1, TrUserData)
+            end
+    end;
+dg_read_field_def_sdl_empty(<<>>, 0, 0, _, F@_1, _) -> #sdl_empty{pkt_id = F@_1}.
+
+d_field_sdl_empty_pkt_id(<<1:1, X:7, Rest/binary>>, N, Acc, F, F@_1, TrUserData) when N < 57 -> d_field_sdl_empty_pkt_id(Rest, N + 7, X bsl N + Acc, F, F@_1, TrUserData);
+d_field_sdl_empty_pkt_id(<<0:1, X:7, Rest/binary>>, N, Acc, F, _, TrUserData) ->
+    {NewFValue, RestF} = {id((X bsl N + Acc) band 4294967295, TrUserData), Rest},
+    dfp_read_field_def_sdl_empty(RestF, 0, 0, F, NewFValue, TrUserData).
+
+skip_varint_sdl_empty(<<1:1, _:7, Rest/binary>>, Z1, Z2, F, F@_1, TrUserData) -> skip_varint_sdl_empty(Rest, Z1, Z2, F, F@_1, TrUserData);
+skip_varint_sdl_empty(<<0:1, _:7, Rest/binary>>, Z1, Z2, F, F@_1, TrUserData) -> dfp_read_field_def_sdl_empty(Rest, Z1, Z2, F, F@_1, TrUserData).
+
+skip_length_delimited_sdl_empty(<<1:1, X:7, Rest/binary>>, N, Acc, F, F@_1, TrUserData) when N < 57 -> skip_length_delimited_sdl_empty(Rest, N + 7, X bsl N + Acc, F, F@_1, TrUserData);
+skip_length_delimited_sdl_empty(<<0:1, X:7, Rest/binary>>, N, Acc, F, F@_1, TrUserData) ->
+    Length = X bsl N + Acc,
+    <<_:Length/binary, Rest2/binary>> = Rest,
+    dfp_read_field_def_sdl_empty(Rest2, 0, 0, F, F@_1, TrUserData).
+
+skip_group_sdl_empty(Bin, _, Z2, FNum, F@_1, TrUserData) ->
+    {_, Rest} = read_group(Bin, FNum),
+    dfp_read_field_def_sdl_empty(Rest, 0, Z2, FNum, F@_1, TrUserData).
+
+skip_32_sdl_empty(<<_:32, Rest/binary>>, Z1, Z2, F, F@_1, TrUserData) -> dfp_read_field_def_sdl_empty(Rest, Z1, Z2, F, F@_1, TrUserData).
+
+skip_64_sdl_empty(<<_:64, Rest/binary>>, Z1, Z2, F, F@_1, TrUserData) -> dfp_read_field_def_sdl_empty(Rest, Z1, Z2, F, F@_1, TrUserData).
+
 decode_msg_sdl_register_super(Bin, TrUserData) ->
     dfp_read_field_def_sdl_register_super(Bin, 0, 0, 0, id(0, TrUserData), id(<<>>, TrUserData), id(0, TrUserData), id(<<>>, TrUserData), id(0, TrUserData), id(0, TrUserData), id(<<>>, TrUserData), id(<<>>, TrUserData), id(<<>>, TrUserData), TrUserData).
 
@@ -2693,6 +2755,7 @@ merge_msgs(Prev, New, MsgName, Opts) ->
     case MsgName of
         sdl_v4_info -> merge_msg_sdl_v4_info(Prev, New, TrUserData);
         sdl_v6_info -> merge_msg_sdl_v6_info(Prev, New, TrUserData);
+        sdl_empty -> merge_msg_sdl_empty(Prev, New, TrUserData);
         sdl_register_super -> merge_msg_sdl_register_super(Prev, New, TrUserData);
         sdl_register_super_ack -> merge_msg_sdl_register_super_ack(Prev, New, TrUserData);
         sdl_register_super_nak -> merge_msg_sdl_register_super_nak(Prev, New, TrUserData);
@@ -2740,6 +2803,13 @@ merge_msg_sdl_v6_info(#sdl_v6_info{port = PFport, v6 = PFv6}, #sdl_v6_info{port
                         true -> NFv6
                      end}.
 
+-compile({nowarn_unused_function,merge_msg_sdl_empty/3}).
+merge_msg_sdl_empty(#sdl_empty{pkt_id = PFpkt_id}, #sdl_empty{pkt_id = NFpkt_id}, _) ->
+    #sdl_empty{pkt_id =
+                   if NFpkt_id =:= undefined -> PFpkt_id;
+                      true -> NFpkt_id
+                   end}.
+
 -compile({nowarn_unused_function,merge_msg_sdl_register_super/3}).
 merge_msg_sdl_register_super(#sdl_register_super{pkt_id = PFpkt_id, client_id = PFclient_id, network_id = PFnetwork_id, mac = PFmac, ip = PFip, mask_len = PFmask_len, hostname = PFhostname, pub_key = PFpub_key, access_token = PFaccess_token},
                              #sdl_register_super{pkt_id = NFpkt_id, client_id = NFclient_id, network_id = NFnetwork_id, mac = NFmac, ip = NFip, mask_len = NFmask_len, hostname = NFhostname, pub_key = NFpub_key, access_token = NFaccess_token}, _) ->
@@ -3125,6 +3195,7 @@ verify_msg(Msg, MsgName, Opts) ->
     case MsgName of
         sdl_v4_info -> v_msg_sdl_v4_info(Msg, [MsgName], TrUserData);
         sdl_v6_info -> v_msg_sdl_v6_info(Msg, [MsgName], TrUserData);
+        sdl_empty -> v_msg_sdl_empty(Msg, [MsgName], TrUserData);
         sdl_register_super -> v_msg_sdl_register_super(Msg, [MsgName], TrUserData);
         sdl_register_super_ack -> v_msg_sdl_register_super_ack(Msg, [MsgName], TrUserData);
         sdl_register_super_nak -> v_msg_sdl_register_super_nak(Msg, [MsgName], TrUserData);
@@ -3183,6 +3254,15 @@ v_msg_sdl_v6_info(#sdl_v6_info{port = F1, v6 = F2}, Path, TrUserData) ->
     ok;
 v_msg_sdl_v6_info(X, Path, _TrUserData) -> mk_type_error({expected_msg, sdl_v6_info}, X, Path).
 
+-compile({nowarn_unused_function,v_msg_sdl_empty/3}).
+-dialyzer({nowarn_function,v_msg_sdl_empty/3}).
+v_msg_sdl_empty(#sdl_empty{pkt_id = F1}, Path, TrUserData) ->
+    if F1 == undefined -> ok;
+       true -> v_type_uint32(F1, [pkt_id | Path], TrUserData)
+    end,
+    ok;
+v_msg_sdl_empty(X, Path, _TrUserData) -> mk_type_error({expected_msg, sdl_empty}, X, Path).
+
 -compile({nowarn_unused_function,v_msg_sdl_register_super/3}).
 -dialyzer({nowarn_function,v_msg_sdl_register_super/3}).
 v_msg_sdl_register_super(#sdl_register_super{pkt_id = F1, client_id = F2, network_id = F3, mac = F4, ip = F5, mask_len = F6, hostname = F7, pub_key = F8, access_token = F9}, Path, TrUserData) ->
@@ -3601,6 +3681,7 @@ get_msg_defs() ->
        #field{name = v4, fnum = 2, rnum = 3, type = bytes, occurrence = defaulty, opts = []},
        #field{name = nat_type, fnum = 3, rnum = 4, type = uint32, occurrence = defaulty, opts = []}]},
      {{msg, sdl_v6_info}, [#field{name = port, fnum = 1, rnum = 2, type = uint32, occurrence = defaulty, opts = []}, #field{name = v6, fnum = 2, rnum = 3, type = bytes, occurrence = defaulty, opts = []}]},
+     {{msg, sdl_empty}, [#field{name = pkt_id, fnum = 1, rnum = 2, type = uint32, occurrence = defaulty, opts = []}]},
      {{msg, sdl_register_super},
       [#field{name = pkt_id, fnum = 1, rnum = 2, type = uint32, occurrence = defaulty, opts = []},
        #field{name = client_id, fnum = 2, rnum = 3, type = string, occurrence = defaulty, opts = []},
@@ -3696,6 +3777,7 @@ get_msg_defs() ->
 get_msg_names() ->
     [sdl_v4_info,
      sdl_v6_info,
+     sdl_empty,
      sdl_register_super,
      sdl_register_super_ack,
      sdl_register_super_nak,
@@ -3723,6 +3805,7 @@ get_group_names() -> [].
 get_msg_or_group_names() ->
     [sdl_v4_info,
      sdl_v6_info,
+     sdl_empty,
      sdl_register_super,
      sdl_register_super_ack,
      sdl_register_super_nak,
@@ -3763,6 +3846,7 @@ find_msg_def(sdl_v4_info) ->
      #field{name = v4, fnum = 2, rnum = 3, type = bytes, occurrence = defaulty, opts = []},
      #field{name = nat_type, fnum = 3, rnum = 4, type = uint32, occurrence = defaulty, opts = []}];
 find_msg_def(sdl_v6_info) -> [#field{name = port, fnum = 1, rnum = 2, type = uint32, occurrence = defaulty, opts = []}, #field{name = v6, fnum = 2, rnum = 3, type = bytes, occurrence = defaulty, opts = []}];
+find_msg_def(sdl_empty) -> [#field{name = pkt_id, fnum = 1, rnum = 2, type = uint32, occurrence = defaulty, opts = []}];
 find_msg_def(sdl_register_super) ->
     [#field{name = pkt_id, fnum = 1, rnum = 2, type = uint32, occurrence = defaulty, opts = []},
      #field{name = client_id, fnum = 2, rnum = 3, type = string, occurrence = defaulty, opts = []},
@@ -3913,6 +3997,7 @@ service_and_rpc_name_to_fqbins(S, R) -> error({gpb_error, {badservice_or_rpc, {S
 
 fqbin_to_msg_name(<<"SDLV4Info">>) -> sdl_v4_info;
 fqbin_to_msg_name(<<"SDLV6Info">>) -> sdl_v6_info;
+fqbin_to_msg_name(<<"SDLEmpty">>) -> sdl_empty;
 fqbin_to_msg_name(<<"SDLRegisterSuper">>) -> sdl_register_super;
 fqbin_to_msg_name(<<"SDLRegisterSuperAck">>) -> sdl_register_super_ack;
 fqbin_to_msg_name(<<"SDLRegisterSuperNak">>) -> sdl_register_super_nak;
@@ -3937,6 +4022,7 @@ fqbin_to_msg_name(E) -> error({gpb_error, {badmsg, E}}).
 
 msg_name_to_fqbin(sdl_v4_info) -> <<"SDLV4Info">>;
 msg_name_to_fqbin(sdl_v6_info) -> <<"SDLV6Info">>;
+msg_name_to_fqbin(sdl_empty) -> <<"SDLEmpty">>;
 msg_name_to_fqbin(sdl_register_super) -> <<"SDLRegisterSuper">>;
 msg_name_to_fqbin(sdl_register_super_ack) -> <<"SDLRegisterSuperAck">>;
 msg_name_to_fqbin(sdl_register_super_nak) -> <<"SDLRegisterSuperNak">>;
@@ -3999,6 +4085,7 @@ get_msg_containment("sdlan_pb") ->
      sdl_arp_response,
      sdl_data,
      sdl_drop_macs_event,
+     sdl_empty,
      sdl_empty_peer_info,
      sdl_nat_changed_event,
      sdl_network_shutdown_event,
@@ -4048,6 +4135,7 @@ get_proto_by_msg_name_as_fqbin(<<"SDLArpRequest">>) -> "sdlan_pb";
 get_proto_by_msg_name_as_fqbin(<<"SDLStunProbe">>) -> "sdlan_pb";
 get_proto_by_msg_name_as_fqbin(<<"SDLArpResponse">>) -> "sdlan_pb";
 get_proto_by_msg_name_as_fqbin(<<"SDLStunProbeReply">>) -> "sdlan_pb";
+get_proto_by_msg_name_as_fqbin(<<"SDLEmpty">>) -> "sdlan_pb";
 get_proto_by_msg_name_as_fqbin(<<"SDLRegisterSuperNak">>) -> "sdlan_pb";
 get_proto_by_msg_name_as_fqbin(<<"SDLRegisterSuperAck">>) -> "sdlan_pb";
 get_proto_by_msg_name_as_fqbin(<<"SDLRegisterAck">>) -> "sdlan_pb";
diff --git a/message.proto b/message.proto
index fe921ea..ce3ed7a 100644
--- a/message.proto
+++ b/message.proto
@@ -1,5 +1,10 @@
 syntax = "proto3";
 
+// 注意
+// 1. network_id, ip地址等分配的逻辑已经迁移到后端https服务
+// 2. 端的强制升级逻辑也迁移到了https服务
+// 3. 假设一个udp包的最大有效负载为1400字节；因此虚拟网卡启动的时候mtu需要控制一下，因为每个包里面都有自己的元数据信息, 端上的mtu值先统一为：1250
+
 // 基础公共类型定义
 
 message SDLV4Info {
@@ -13,27 +18,34 @@ message SDLV6Info {
     bytes v6 = 2;
 }
 
-// 所有需要建立请求和响应对应关系的，都是通过udp包头部4字节的packetId来对应
+message SDLEmpty {
+    uint32 pkt_id = 1;
+}
 
-// 客户端层面通过token或者账号密码登录, 服务器端不管这个，
-// 只是验证凭证是否合法 (access_token)
 // 这里修改成了扁平的结构, 否则有些字段不好找放的位置
 message SDLRegisterSuper {
+    // 所有需要建立请求和响应对应关系的，都是通过4字节的pktId来对应
     uint32 pkt_id = 1;
     string client_id = 2;
+    // 网络地址信息已经有https请求分配了
+    // 注册的时候需要带上(network_id, mac, ip, mask_len, hostname)
     uint32 network_id = 3;
     bytes mac = 4;
     uint32 ip = 5;
     uint32 mask_len = 6;
     string hostname = 7;
+
     string pub_key = 8;
+    // 客户端使用http协议请求后端，通过token或者账号密码登录时, 统一返回一个access_token;
+    // RegisterSuper的时候，验证凭证是否合法 (access_token)
     string access_token = 9;
 }
 
-// 这里修改成了udp的方式，后续需要验证: session_token
 message SDLRegisterSuperAck {
     uint32 pkt_id = 1;
     bytes aes_key = 2;
+    // 验证通过后，返回session_token; 后续通讯的合法行需哟啊通过session_token来保证
+    // 在SDLQueryInfo，SDLStunRequest, SDLData, SDLArpRequest等需要服务器端介入的地方都增加了session_token的验证(端和端之间的SDLData不需要校验)
     bytes session_token = 3;
 }
 
@@ -76,12 +88,14 @@ message SDLNatChangedEvent {
 }
 
 // 被清理掉的Endpoints
+// 协议改成udp后，服务端只能通过定时器来集中清理掉线的端（通过心跳机制SDLStunRequest）
 message SDLDropMacsEvent {
     uint32 network_id = 1;
     repeated bytes macs = 2;
 }
 
 // 通知端上必须重新校验
+// 服务器端认为端已经掉线了，但是这个时候还在向服务端发送消息；服务端要求端上重新校验(SDLRegisterSuper)
 message SDLRefreshAuthEvent {
     uint32 network_id = 1;
 }
@@ -119,6 +133,8 @@ message SDLData {
     uint32 ttl = 5;
     bytes data = 6;
     bytes session_token = 7;
+    // 端通过https登录的时候，服务端会分配该端对应的权限标识
+    // 后续的请求过程中需要带上这个值，对端通过这个值要判断对数据包是否放行
     uint32 identity_id = 8;
 }
 
@@ -141,18 +157,20 @@ message SDLRegisterAck {
 message SDLStunProbe {
     uint32 cookie = 1;
     uint32 attr = 2;
+    // 增加step是为了方便端上判断，收到的请求和响应之间的映射关系；服务器端原样返回
     uint32 step = 3;
 }
 
 message SDLStunProbeReply {
     uint32 cookie = 1;
+    // 增加step是为了方便端上判断，收到的请求和响应之间的映射关系；服务器端原样返回
     uint32 step = 2;
     uint32 port = 3;
     uint32 ip = 4;
 }
 
 // ARP查询相关
-
+// 真实的arp请求是通过广播的形式获取到的，但是针对于macos这种tun的实现；是能够分析出arp请求包的；对于当前网络来说，服务端是知道mac对应的ip地址的，因此没有必要广播；直接通过服务器端返回
 message SDLArpRequest {
     uint32 network_id = 1;
     uint32 target_ip = 2;