开发部署在云端的设备接入网关服务就不得不提到MQTT,使用MQTT不论是从设备到设备,还是设备到云端服务的双向通讯,都可以获得较好的支持。

MQTT的起源和我的理解

用tcpdump分析下MQTT的通讯时序

这里基于mosquitto,以一组实际的订阅、发布,使用tcpdump来观察MQTT的通讯。

# 使用tcpdump打印指定MQTT服务器所在端口的报文
tcpdump -n -XX -i eth0 port 1883
# 订阅指定主题的消息
mosquitto_sub -h 172.16.0.12 -t "topic/#" -u user -P password -i "client1"
# 发布消息到指定主题
mosquitto_pub -h 172.16.0.12 -t "topic/" -u user -P password  -i "client3" -m "1234567890123456789012345678901234567890"

tcpdump抓取的报文如下:

启动mosquitto_sub命令获得如下报文:
==================================
16:33:28.668926 IP SUB.41050 > MQTT.ibm-mqisdp: Flags [S], seq 1177792969, win 29200, options [mss 1424,sackOK,TS val 530570732 ecr 0,nop,wscale 7], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  003c 5872 4000 3806 556b 5147 9713 ac10  .<Xr@.8.UkQG....0x0020:  000c a05a 075b 4633 b1c9 0000 0000 a002  ...Z.[F3........0x0030:  7210 a45e 0000 0204 0590 0402 080a 1f9f  r..^............0x0040:  ddec 0000 0000 0103 0307                 ..........
16:33:28.669001 IP MQTT.ibm-mqisdp >SUB.41050: Flags [S.], seq 1053629863, ack 1177792970, win 28960, options [mss 1460,sackOK,TS val 3885354501 ecr 530570732,nop,wscale 7], length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  003c 0000 4000 4006 a645 ac10 000c 5147  .<..@.@..E....QG0x0020:  9713 075b a05a 3ecd 1da7 4633 b1ca a012  ...[.Z>...F3....0x0030:  7120 9309 0000 0204 05b4 0402 080a e795  q...............0x0040:  ce05 1f9f ddec 0103 0307                 ..........
16:33:28.672229 IP SUB.41050 > MQTT.ibm-mqisdp: Flags [.], ack 1, win 229, options [nop,nop,TS val 530570735 ecr 3885354501], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 5873 4000 3806 5572 5147 9713 ac10  .4Xs@.8.UrQG....0x0020:  000c a05a 075b 4633 b1ca 3ecd 1da8 8010  ...Z.[F3..>.....0x0030:  00e5 320e 0000 0101 080a 1f9f ddef e795  ..2.............0x0040:  ce05                                     ..
16:33:28.672280 IP SUB.41050 > MQTT.ibm-mqisdp: Flags [P.], seq 1:42, ack 1, win 229, options [nop,nop,TS val 530570735 ecr 3885354501], length 410x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  005d 5874 4000 3806 5548 5147 9713 ac10  .]Xt@.8.UHQG....0x0020:  000c a05a 075b 4633 b1ca 3ecd 1da8 8018  ...Z.[F3..>.....0x0030:  00e5 37b7 0000 0101 080a 1f9f ddef e795  ..7.............0x0040:  ce05 1027 0006 4d51 4973 6470 03c2 003c  ...'..MQIsdp...<0x0050:  0007 636c 6965 6e74 3100 0563 636e 6574  ..client1..ccnet0x0060:  0009 6363 6e65 7430 3930 31              ..ccnet0901
16:33:28.672313 IP MQTT.ibm-mqisdp > SUB.41050: Flags [.], ack 42, win 227, options [nop,nop,TS val 3885354505 ecr 530570735], length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0034 d3a1 4000 4006 d2ab ac10 000c 5147  .4..@.@.......QG0x0020:  9713 075b a05a 3ecd 1da8 4633 b1f3 8010  ...[.Z>...F3....0x0030:  00e3 31e3 0000 0101 080a e795 ce09 1f9f  ..1.............0x0040:  ddef                                     ..
16:33:28.672562 IP MQTT.ibm-mqisdp > SUB.41050: Flags [P.], seq 1:5, ack 42, win 227, options [nop,nop,TS val 3885354505 ecr 530570735], length 40x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0038 d3a2 4000 4006 d2a6 ac10 000c 5147  .8..@.@.......QG0x0020:  9713 075b a05a 3ecd 1da8 4633 b1f3 8018  ...[.Z>...F3....0x0030:  00e3 11d5 0000 0101 080a e795 ce09 1f9f  ................0x0040:  ddef 2002 0000                           ......
16:33:28.675753 IP SUB.41050 > MQTT.ibm-mqisdp: Flags [.], ack 5, win 229, options [nop,nop,TS val 530570739 ecr 3885354505], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 5875 4000 3806 5570 5147 9713 ac10  .4Xu@.8.UpQG....0x0020:  000c a05a 075b 4633 b1f3 3ecd 1dac 8010  ...Z.[F3..>.....0x0030:  00e5 31d9 0000 0101 080a 1f9f ddf3 e795  ..1.............0x0040:  ce09                                     ..
16:33:28.675772 IP SUB.41050 > MQTT.ibm-mqisdp: Flags [P.], seq 42:56, ack 5, win 229, options [nop,nop,TS val 530570739 ecr 3885354505], length 140x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0042 5876 4000 3806 5561 5147 9713 ac10  .BXv@.8.UaQG....0x0020:  000c a05a 075b 4633 b1f3 3ecd 1dac 8018  ...Z.[F3..>.....0x0030:  00e5 46b6 0000 0101 080a 1f9f ddf3 e795  ..F.............0x0040:  ce09 820c 0001 0007 6363 6e65 742f 2300  ........ccnet/#.
16:33:28.675823 IP MQTT.ibm-mqisdp > SUB.41050: Flags [P.], seq 5:10, ack 56, win 227, options [nop,nop,TS val 3885354508 ecr 530570739], length 50x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0039 d3a3 4000 4006 d2a4 ac10 000c 5147  .9..@.@.......QG0x0020:  9713 075b a05a 3ecd 1dac 4633 b201 8018  ...[.Z>...F3....0x0030:  00e3 a1b8 0000 0101 080a e795 ce0c 1f9f  ................0x0040:  ddf3 9003 0001 00                        .......
16:33:28.719501 IP SUB.41050 > MQTT.ibm-mqisdp: Flags [.], ack 10, win 229, options [nop,nop,TS val 530570783 ecr 3885354508], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 5877 4000 3806 556e 5147 9713 ac10  .4Xw@.8.UnQG....0x0020:  000c a05a 075b 4633 b201 3ecd 1db1 8010  ...Z.[F3..>.....0x0030:  00e5 3197 0000 0101 080a 1f9f de1f e795  ..1.............0x0040:  ce0c                                     ..
终止mosquitto_sub命令获得如下报文:
=================================
16:29:54.745664 IP 81.71.151.19.40510 > 172.16.0.12.ibm-mqisdp: Flags [F.], seq 58, ack 12, win 229, options [nop,nop,TS val 530356809 ecr 3885119146], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 e1fc 4000 3806 cbe8 5147 9713 ac10  .4..@.8...QG....0x0020:  000c 9e3e 075b 0e6c ea6f 989b b7f8 8011  ...>.[.l.o......0x0030:  00e5 1a34 0000 0101 080a 1f9c 9a49 e792  ...4.........I..0x0040:  36aa                                     6.
16:29:54.745761 IP 172.16.0.12.ibm-mqisdp > 81.71.151.19.40510: Flags [F.], seq 12, ack 59, win 227, options [nop,nop,TS val 3885140578 ecr 530356809], length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0034 fbe4 4000 4006 aa68 ac10 000c 5147  .4..@.@..h....QG0x0020:  9713 075b 9e3e 989b b7f8 0e6c ea70 8011  ...[.>.....l.p..0x0030:  00e3 c67c 0000 0101 080a e792 8a62 1f9c  ...|.........b..0x0040:  9a49                                     .I
16:29:54.751445 IP 81.71.151.19.40510 > 172.16.0.12.ibm-mqisdp: Flags [.], ack 13, win 229, options [nop,nop,TS val 530356812 ecr 3885140578], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 e1fd 4000 3806 cbe7 5147 9713 ac10  .4..@.8...QG....0x0020:  000c 9e3e 075b 0e6c ea70 989b b7f9 8010  ...>.[.l.p......0x0030:  00e5 c677 0000 0101 080a 1f9c 9a4c e792  ...w.........L..0x0040:  8a62                                     .b
# 执行mosquitto_pub后得到的报文如下:
16:36:40.721513 IP 81.71.151.19.41390 > 172.16.0.12.ibm-mqisdp: Flags [S], seq 2807988728, win 29200, options [mss 1424,sackOK,TS val 530762785 ecr 0,nop,wscale 7], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  003c 5dd0 4000 3806 500d 5147 9713 ac10  .<].@.8.P.QG....0x0020:  000c a1ae 075b a75e 81f8 0000 0000 a002  .....[.^........0x0030:  7210 8378 0000 0204 0590 0402 080a 1fa2  r..x............0x0040:  cc21 0000 0000 0103 0307                 .!........
16:36:40.721585 IP 172.16.0.12.ibm-mqisdp > 81.71.151.19.41390: Flags [S.], seq 4236199326, ack 2807988729, win 28960, options [mss 1460,sackOK,TS val 3885546554 ecr 530762785,nop,wscale 7], length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  003c 0000 4000 4006 a645 ac10 000c 5147  .<..@.@..E....QG0x0020:  9713 075b a1ae fc7f 459e a75e 81f9 a012  ...[....E..^....0x0030:  7120 9e41 0000 0204 05b4 0402 080a e798  q..A............0x0040:  bc3a 1fa2 cc21 0103 0307                 .:...!....
16:36:40.724732 IP 81.71.151.19.41390 > 172.16.0.12.ibm-mqisdp: Flags [.], ack 1, win 229, options [nop,nop,TS val 530762788 ecr 3885546554], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 5dd1 4000 3806 5014 5147 9713 ac10  .4].@.8.P.QG....0x0020:  000c a1ae 075b a75e 81f9 fc7f 459f 8010  .....[.^....E...0x0030:  00e5 3d46 0000 0101 080a 1fa2 cc24 e798  ..=F.........$..0x0040:  bc3a                                     .:
16:36:40.724750 IP PUB.41390 > MQTT.ibm-mqisdp: Flags [P.], seq 1:42, ack 1, win 229, options [nop,nop,TS val 530762788 ecr 3885546554], length 410x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  005d 5dd2 4000 3806 4fea 5147 9713 ac10  .]].@.8.O.QG....0x0020:  000c a1ae 075b a75e 81f9 fc7f 459f 8018  .....[.^....E...0x0030:  00e5 40ef 0000 0101 080a 1fa2 cc24 e798  ..@..........$..0x0040:  bc3a 1027 0006 4d51 4973 6470 03c2 003c  .:.'..MQIsdp...<0x0050:  0007 636c 6965 6e74 3300 0563 636e 6574  ..client3..ccnet0x0060:  0009 6363 6e65 7430 3930 31              ..ccnet0901
16:36:40.724787 IP 172.16.0.12.ibm-mqisdp > 81.71.151.19.41390: Flags [.], ack 42, win 227, options [nop,nop,TS val 3885546557 ecr 530762788], length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0034 f9a2 4000 4006 acaa ac10 000c 5147  .4..@.@.......QG0x0020:  9713 075b a1ae fc7f 459f a75e 8222 8010  ...[....E..^."..0x0030:  00e3 3d1c 0000 0101 080a e798 bc3d 1fa2  ..=..........=..0x0040:  cc24                                     .$
16:36:40.724978 IP 172.16.0.12.ibm-mqisdp > 81.71.151.19.41390: Flags [P.], seq 1:5, ack 42, win 227, options [nop,nop,TS val 3885546557 ecr 530762788], length 40x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0038 f9a3 4000 4006 aca5 ac10 000c 5147  .8..@.@.......QG0x0020:  9713 075b a1ae fc7f 459f a75e 8222 8018  ...[....E..^."..0x0030:  00e3 1d0e 0000 0101 080a e798 bc3d 1fa2  .............=..0x0040:  cc24 2002 0000                           .$....
16:36:40.728114 IP 81.71.151.19.41390 > 172.16.0.12.ibm-mqisdp: Flags [.], ack 5, win 229, options [nop,nop,TS val 530762791 ecr 3885546557], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 5dd3 4000 3806 5012 5147 9713 ac10  .4].@.8.P.QG....0x0020:  000c a1ae 075b a75e 8222 fc7f 45a3 8010  .....[.^."..E...0x0030:  00e5 3d13 0000 0101 080a 1fa2 cc27 e798  ..=..........'..0x0040:  bc3d                                     .=
16:36:40.728144 IP PUB.41390 > MQTT.ibm-mqisdp: Flags [P.], seq 42:82, ack 5, win 229, options [nop,nop,TS val 530762791 ecr 3885546557], length 400x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  005c 5dd4 4000 3806 4fe9 5147 9713 ac10  .\].@.8.O.QG....0x0020:  000c a1ae 075b a75e 8222 fc7f 45a3 8018  .....[.^."..E...0x0030:  00e5 a8af 0000 0101 080a 1fa2 cc27 e798  .............'..0x0040:  bc3d 3026 0006 6363 6e65 742f 3132 3334  .=0&..ccnet/12340x0050:  3536 3738 3930 3132 3334 3536 3738 3930  56789012345678900x0060:  3132 3334 3536 3738 3930                 1234567890
16:36:40.728146 IP 81.71.151.19.41390 > 172.16.0.12.ibm-mqisdp: Flags [FP.], seq 82:84, ack 5, win 229, options [nop,nop,TS val 530762791 ecr 3885546557], length 20x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0036 5dd5 4000 3806 500e 5147 9713 ac10  .6].@.8.P.QG....0x0020:  000c a1ae 075b a75e 824a fc7f 45a3 8019  .....[.^.J..E...0x0030:  00e5 5cdf 0000 0101 080a 1fa2 cc27 e798  ..\..........'..0x0040:  bc3d e000                                .=..
16:36:40.728230 IP MQTT.ibm-mqisdp > SUB.41050: Flags [P.], seq 96:136, ack 62, win 227, options [nop,nop,TS val 3885546560 ecr 530753903], length 400x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  005c d3a9 4000 4006 d27b ac10 000c 5147  .\..@.@..{....QG0x0020:  9713 075b a05a 3ecd 1e07 4633 b207 8018  ...[.Z>...F3....0x0030:  00e3 e34f 0000 0101 080a e798 bc40 1fa2  ...O.........@..0x0040:  a96f 3026 0006 6363 6e65 742f 3132 3334  .o0&..ccnet/12340x0050:  3536 3738 3930 3132 3334 3536 3738 3930  56789012345678900x0060:  3132 3334 3536 3738 3930                 1234567890
16:36:40.728288 IP 172.16.0.12.ibm-mqisdp > 81.71.151.19.41390: Flags [.], ack 85, win 227, options [nop,nop,TS val 3885546561 ecr 530762791], length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0034 f9a4 4000 4006 aca8 ac10 000c 5147  .4..@.@.......QG0x0020:  9713 075b a1ae fc7f 45a3 a75e 824d 8010  ...[....E..^.M..0x0030:  00e3 3ce6 0000 0101 080a e798 bc41 1fa2  ..<..........A..0x0040:  cc27                                     .'
16:36:40.728367 IP 172.16.0.12.ibm-mqisdp > 81.71.151.19.41390: Flags [F.], seq 5, ack 85, win 227, options [nop,nop,TS val 3885546561 ecr 530762791], length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0034 f9a5 4000 4006 aca7 ac10 000c 5147  .4..@.@.......QG0x0020:  9713 075b a1ae fc7f 45a3 a75e 824d 8011  ...[....E..^.M..0x0030:  00e3 3ce5 0000 0101 080a e798 bc41 1fa2  ..<..........A..0x0040:  cc27                                     .'
16:36:40.731431 IP 81.71.151.19.41050 > 172.16.0.12.ibm-mqisdp: Flags [.], ack 136, win 229, options [nop,nop,TS val 530762794 ecr 3885546560], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 5880 4000 3806 5565 5147 9713 ac10  .4X.@.8.UeQG....0x0020:  000c a05a 075b 4633 b207 3ecd 1e2f 8010  ...Z.[F3..>../..0x0030:  00e5 54ce 0000 0101 080a 1fa2 cc2a e798  ..T..........*..0x0040:  bc40                                     .@
16:36:40.731575 IP 81.71.151.19.41390 > 172.16.0.12.ibm-mqisdp: Flags [.], ack 6, win 229, options [nop,nop,TS val 530762795 ecr 3885546561], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 0000 4000 3806 ade5 5147 9713 ac10  .4..@.8...QG....0x0020:  000c a1ae 075b a75e 824d fc7f 45a4 8010  .....[.^.M..E...0x0030:  00e5 3cdf 0000 0101 080a 1fa2 cc2b e798  ..<..........+..0x0040:  bc41                                     .A可重点关注红色部分,其余都是TCP握手和收报报文的常规交互,可知道MQTT订阅发布的完整时序如下:

MQTT发布订阅的实际交互时序图

可以看到AUHT、SUB、PUB、SEND_MESSAGE的报文非常精简,基本只是对必须传送的字段增加了两个字节的长度,因此其对带宽是非常节省的。

再分析下支持websockets时的通讯时序

# 启动对9001端口的监视
tcpdump -n -XX -i eth0 port 9001
# 订阅指定主题的消息
mosquitto_sub -h 172.16.0.12 -t "topic/#" -u user -P password -i "client1"
#编写一个基于websockets访问mqtt的页面,如下亲测通过;  点击init按钮
<html><head><script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/paho-mqtt/1.0.2/mqttws31.js"></script></head><body><script>var mqtt;var host = '81.71.87.37';var port = 9001;// onConnect 事件function onConnect() {console.log('connected.');/*var raw_message = 'Hello World!';message = new Paho.MQTT.Message(raw_message);message.destinationName = 'ccnet/up/abc';console.log('sending message: ' + raw_message );mqtt.send(message);*/// 订阅 download topicvar subOptions = {qos: 1,onSuccess: onSubscribe};mqtt.subscribe('ccnet/#', subOptions);}function onSend() {console.log('onSend.');var raw_message = 'Hello World!';message = new Paho.MQTT.Message(raw_message);message.destinationName = 'ccnet/up/abc';console.log('sending message: ' + raw_message );mqtt.send(message);}// 订阅主题成功事件function onSubscribe(context) {console.log('subscribe success');console.log(context);}// 连接失败事件function onFailure(message) {console.log('connect failed.');}// onMessageArrived 事件function onMessageArrived(message) {console.log('new message arrived...');console.log(message.payloadString);}// 建立 MQTT websocket 连接function MQTTconnect() {console.log('connecting to ' + host + ':' + port);mqtt = new Paho.MQTT.Client(host, port, 'clientid');var options = {timeout: 3,onSuccess: onConnect,onFailure: onFailure,userName: 'ccnet',password: 'ccnet0901',mqttVersion: 4};mqtt.onMessageArrived = onMessageArrived;mqtt.connect(options);}</script><input  type="button" value="Init" onclick="javascript:MQTTconnect();"/> <input  type="button" value="Send" onclick="javascript:onSend();"/></body>
</html>
# 发布消息到指定主题
mosquitto_pub -h 172.16.0.12 -t "topic/" -u user -P password  -i "client3" -m "1234567890123456789012345678901234567890"

TCPDUMP抓取的报文如下:

# 点击WEB页面上的Init按钮之后
18:11:49.183098 IP 14.150.108.187.50999 > 172.16.0.12.etlservicemgr: Flags [S], seq 3659468570, win 64240, options [mss 1360,nop,wscale 8,nop,nop,sackOK], length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0034 7b4e 4000 7206 65a0 0e96 6cbb ac10  .4{N@.r.e...l...0x0020:  000c c737 2329 da1f 0f1a 0000 0000 8002  ...7#)..........0x0030:  faf0 797b 0000 0204 0550 0103 0308 0101  ..y{.....P......0x0040:  0402                                     ..
18:11:49.183188 IP 172.16.0.12.etlservicemgr > 14.150.108.187.50999: Flags [S.], seq 3730879023, ack 3659468571, win 29200, options [mss 1460,nop,nop,sackOK,nop,wscale 7], length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0034 0000 4000 4006 1357 ac10 000c 0e96  .4..@.@..W......0x0020:  6cbb 2329 c737 de60 b22f da1f 0f1b 8012  l.#).7.`./......0x0030:  7210 7157 0000 0204 05b4 0101 0402 0103  r.qW............0x0040:  0307                                     ..
18:11:49.223085 IP 14.150.108.187.50999 > 172.16.0.12.etlservicemgr: Flags [.], ack 1, win 515, length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0028 7b4f 4000 7206 65ab 0e96 6cbb ac10  .({O@.r.e...l...0x0020:  000c c737 2329 da1f 0f1b de60 b230 5010  ...7#).....`.0P.0x0030:  0203 2237 0000                           .."7..
18:11:49.247331 IP Browser.50999 > MQTT.etlservicemgr: Flags [P.], seq 1:511, ack 1, win 515, length 5100x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0226 7b50 4000 7206 63ac 0e96 6cbb ac10  .&{P@.r.c...l...0x0020:  000c c737 2329 da1f 0f1b de60 b230 5018  ...7#).....`.0P.0x0030:  0203 d122 0000 4745 5420 2f6d 7174 7420  ..."..GET./mqtt.0x0040:  4854 5450 2f31 2e31 0d0a 486f 7374 3a20  HTTP/1.1..Host:.0x0050:  3831 2e37 312e 3837 2e33 373a 3930 3031  81.71.87.37:90010x0060:  0d0a 436f 6e6e 6563 7469 6f6e 3a20 5570  ..Connection:.Up0x0070:  6772 6164 650d 0a50 7261 676d 613a 206e  grade..Pragma:.n0x0080:  6f2d 6361 6368 650d 0a43 6163 6865 2d43  o-cache..Cache-C0x0090:  6f6e 7472 6f6c 3a20 6e6f 2d63 6163 6865  ontrol:.no-cache0x00a0:  0d0a 5573 6572 2d41 6765 6e74 3a20 4d6f  ..User-Agent:.Mo0x00b0:  7a69 6c6c 612f 352e 3020 2857 696e 646f  zilla/5.0.(Windo0x00c0:  7773 204e 5420 3130 2e30 3b20 5769 6e36  ws.NT.10.0;.Win60x00d0:  343b 2078 3634 2920 4170 706c 6557 6562  4;.x64).AppleWeb0x00e0:  4b69 742f 3533 372e 3336 2028 4b48 544d  Kit/537.36.(KHTM0x00f0:  4c2c 206c 696b 6520 4765 636b 6f29 2043  L,.like.Gecko).C0x0100:  6872 6f6d 652f 3130 312e 302e 3439 3531  hrome/101.0.49510x0110:  2e36 3720 5361 6661 7269 2f35 3337 2e33  .67.Safari/537.30x0120:  360d 0a55 7067 7261 6465 3a20 7765 6273  6..Upgrade:.webs0x0130:  6f63 6b65 740d 0a4f 7269 6769 6e3a 206e  ocket..Origin:.n0x0140:  756c 6c0d 0a53 6563 2d57 6562 536f 636b  ull..Sec-WebSock0x0150:  6574 2d56 6572 7369 6f6e 3a20 3133 0d0a  et-Version:.13..0x0160:  4163 6365 7074 2d45 6e63 6f64 696e 673a  Accept-Encoding:0x0170:  2067 7a69 702c 2064 6566 6c61 7465 0d0a  .gzip,.deflate..0x0180:  4163 6365 7074 2d4c 616e 6775 6167 653a  Accept-Language:0x0190:  207a 682d 434e 2c7a 683b 713d 302e 390d  .zh-CN,zh;q=0.9.0x01a0:  0a53 6563 2d57 6562 536f 636b 6574 2d4b  .Sec-WebSocket-K0x01b0:  6579 3a20 7938 796a 3756 7858 624b 576f  ey:.y8yj7VxXbKWo0x01c0:  4f45 6962 3248 7176 4b51 3d3d 0d0a 5365  OEib2HqvKQ==..Se0x01d0:  632d 5765 6253 6f63 6b65 742d 4578 7465  c-WebSocket-Exte0x01e0:  6e73 696f 6e73 3a20 7065 726d 6573 7361  nsions:.permessa0x01f0:  6765 2d64 6566 6c61 7465 3b20 636c 6965  ge-deflate;.clie0x0200:  6e74 5f6d 6178 5f77 696e 646f 775f 6269  nt_max_window_bi0x0210:  7473 0d0a 5365 632d 5765 6253 6f63 6b65  ts..Sec-WebSocke0x0220:  742d 5072 6f74 6f63 6f6c 3a20 6d71 7474  t-Protocol:.mqtt0x0230:  0d0a 0d0a                                ....
18:11:49.247360 IP 172.16.0.12.etlservicemgr > 14.150.108.187.50999: Flags [.], ack 511, win 237, length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0028 653f 4000 4006 ae23 ac10 000c 0e96  .(e?@.@..#......0x0020:  6cbb 2329 c737 de60 b230 da1f 1119 5010  l.#).7.`.0....P.0x0030:  00ed 214f 0000                           ..!O..
18:11:49.323395 IP 172.16.0.12.etlservicemgr > 14.150.108.187.50999: Flags [P.], seq 1:160, ack 511, win 237, length 1590x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  00c7 6540 4000 4006 ad83 ac10 000c 0e96  ..e@@.@.........0x0020:  6cbb 2329 c737 de60 b230 da1f 1119 5018  l.#).7.`.0....P.0x0030:  00ed df2c 0000 4854 5450 2f31 2e31 2031  ...,..HTTP/1.1.10x0040:  3031 2053 7769 7463 6869 6e67 2050 726f  01.Switching.Pro0x0050:  746f 636f 6c73 0d0a 5570 6772 6164 653a  tocols..Upgrade:0x0060:  2057 6562 536f 636b 6574 0d0a 436f 6e6e  .WebSocket..Conn0x0070:  6563 7469 6f6e 3a20 5570 6772 6164 650d  ection:.Upgrade.0x0080:  0a53 6563 2d57 6562 536f 636b 6574 2d41  .Sec-WebSocket-A0x0090:  6363 6570 743a 204a 6845 6544 4534 6468  ccept:.JhEeDE4dh0x00a0:  6462 2b4b 6a47 4f52 452b 595a 7176 424b  db+KjGORE+YZqvBK0x00b0:  2f34 3d0d 0a53 6563 2d57 6562 536f 636b  /4=..Sec-WebSock0x00c0:  6574 2d50 726f 746f 636f 6c3a 206d 7174  et-Protocol:.mqt0x00d0:  740d 0a0d 0a                             t....
18:11:49.392070 IP 14.150.108.187.50999 > 172.16.0.12.etlservicemgr: Flags [P.], seq 511:557, ack 160, win 514, length 460x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0056 7b54 4000 7206 6578 0e96 6cbb ac10  .V{T@.r.ex..l...0x0020:  000c c737 2329 da1f 1119 de60 b2cf 5018  ...7#).....`..P.0x0030:  0202 7640 0000 82a8 a399 adbd b3bf adb9  ..v@............0x0040:  eec8 f9e9 a75b ad81 a391 ced1 cafc c3c9  .....[..........0x0050:  cafd adb8 c0fa c3d8 d799 a4de c0f7 c8c9  ................0x0060:  93a0 9d8c                                ....
18:11:49.392100 IP 172.16.0.12.etlservicemgr > 14.150.108.187.50999: Flags [.], ack 557, win 237, length 00x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0028 6541 4000 4006 ae21 ac10 000c 0e96  .(eA@.@..!......0x0020:  6cbb 2329 c737 de60 b2cf da1f 1147 5010  l.#).7.`.....GP.0x0030:  00ed 2082 0000                           ......
18:11:49.392352 IP 172.16.0.12.etlservicemgr > 14.150.108.187.50999: Flags [P.], seq 160:166, ack 557, win 237, length 60x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  002e 6542 4000 4006 ae1a ac10 000c 0e96  ..eB@.@.........0x0020:  6cbb 2329 c737 de60 b2cf da1f 1147 5018  l.#).7.`.....GP.0x0030:  00ed 7e6d 0000 8204 2002 0000            ..~m........
18:11:49.443110 IP 14.150.108.187.50999 > 172.16.0.12.etlservicemgr: Flags [.], ack 166, win 514, length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0028 7b56 4000 7206 65a4 0e96 6cbb ac10  .({V@.r.e...l...0x0020:  000c c737 2329 da1f 1147 de60 b2d5 5010  ...7#)...G.`..P.0x0030:  0202 1f67 0000                           ...g..
18:11:49.451571 IP 14.150.108.187.50999 > 172.16.0.12.etlservicemgr: Flags [P.], seq 557:577, ack 166, win 514, length 200x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  003c 7b57 4000 7206 658f 0e96 6cbb ac10  .<{W@.r.e...l...0x0020:  000c c737 2329 da1f 1147 de60 b2d5 5018  ...7#)...G.`..P.0x0030:  0202 5568 0000 828e 2670 37fd a47c 37fc  ..Uh....&p7..|7.0x0040:  2677 549e 4815 43d2 0571                 &wT.H.C..q
18:11:49.451667 IP 172.16.0.12.etlservicemgr > 14.150.108.187.50999: Flags [P.], seq 166:173, ack 577, win 237, length 70x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  002f 6543 4000 4006 ae18 ac10 000c 0e96  ./eC@.@.........0x0020:  6cbb 2329 c737 de60 b2d5 da1f 115b 5018  l.#).7.`.....[P.0x0030:  00ed 0d4f 0000 8205 9003 0001 01         ...O.........
18:11:49.543376 IP 14.150.108.187.50999 > 172.16.0.12.etlservicemgr: Flags [.], ack 173, win 514, length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0028 7b59 4000 7206 65a1 0e96 6cbb ac10  .({Y@.r.e...l...0x0020:  000c c737 2329 da1f 115b de60 b2dc 5010  ...7#)...[.`..P.0x0030:  0202 1f4c 0000                           ...L..# 点击Send按钮之后
18:16:59.642995 IP Browser.50999 > MQTT.etlservicemgr: Flags [P.], seq 677:711, ack 249, win 514, length 340x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  004a 7c2e 4000 7206 64aa 0e96 6cbb ac10  .J|.@.r.d...l...0x0020:  000c c737 2329 da1f 11bf de60 b328 5018  ...7#).....`.(P.0x0030:  0202 736b 0000 829c 69c7 926a 59dd 9266  ..sk....i..jY..f0x0040:  0aa4 fc0f 1de8 e71a 46a6 f009 21a2 fe06  ........F...!...0x0050:  06e7 c505 1bab f64b                      .......K
18:16:59.643148 IP MQTT.etlservicemgr > Browser.50999: Flags [P.], seq 249:279, ack 711, win 237, length 300x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0046 654b 4000 4006 adf9 ac10 000c 0e96  .FeK@.@.........0x0020:  6cbb 2329 c737 de60 b328 da1f 11e1 5018  l.#).7.`.(....P.0x0030:  00ed ce09 0000 821c 301a 000c 6363 6e65  ........0...ccne0x0040:  742f 7570 2f61 6263 4865 6c6c 6f20 576f  t/up/abcHello.Wo0x0050:  726c 6421                                rld!
18:16:59.743220 IP 14.150.108.187.50999 > 172.16.0.12.etlservicemgr: Flags [.], ack 279, win 514, length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0028 7c30 4000 7206 64ca 0e96 6cbb ac10  .(|0@.r.d...l...0x0020:  000c c737 2329 da1f 11e1 de60 b346 5010  ...7#).....`.FP.0x0030:  0202 1e5c 0000                           ...\..
# 执行发布消息命令之后
17:56:50.992944 IP MQTT.etlservicemgr > Browser.50939: Flags [P.], seq 205:247, ack 675, win 237, length 420x0000:  feee 809f 3247 5254 00e4 a55c 0800 4500  ....2GRT...\..E.0x0010:  0052 e2f9 4000 4006 303f ac10 000c 0e96  .R..@.@.0?......0x0020:  6cbb 2329 c6fb c3b7 103a 2e40 d9e6 5018  l.#).....:.@..P.0x0030:  00ed aaae 0000 8228 3026 0006 6363 6e65  .......(0&..ccne0x0040:  742f 3132 3334 3536 3738 3930 3132 3334  t/123456789012340x0050:  3536 3738 3930 3132 3334 3536 3738 3930  5678901234567890
17:56:51.100524 IP 14.150.108.187.50939 > 172.16.0.12.etlservicemgr: Flags [.], ack 247, win 514, length 00x0000:  5254 00e4 a55c feee 809f 3247 0800 4568  RT...\....2G..Eh0x0010:  0028 77db 4000 7206 691f 0e96 6cbb ac10  .(w.@.r.i...l...0x0020:  000c c6fb 2329 2e40 d9e6 c3b7 1064 5010  ....#).@.....dP.0x0030:  0202 bffd 0000                           ......

特别的查看以上红色报文,可看到基于websockets的通讯整体协作图如下:

MQTT在websockets下的工作模式

可以看到除了在建立websockets时,有较大的http头信息,其余仍然很精简。而且websocket已经对Browser上送的AUTH、SUB、PUB进行了加密处理,但是对于下发到Browser的信息并没有进行加密处理

使用Mosquitto搭建支持Websockets的MQTT服务

这里使用了mosquitto-2.0.11,下载源码后,修改下config.mk文件,将WITH_WEBSOCKETS打开,如下

# Build with websockets support on the broker.
WITH_WEBSOCKETS:=yes

这里是在centos下工作的,如果没有websockets库,需要安装

yum install libwebsockets* -y

然后就是一路的make,make install,之后配置下LD_LIBRARY_PATH的环境变量,就可以开始工作了。

LD_LIBRARY_PATH=:/root/setup/mosquitto-2.0.11/lib:/root/setup/cJSON-1.7.14

配置mosquitto环境,可建立一个专门的目录,将mosquitto.conf文件拷贝过来修改,目录结构如下:

<root@VM-0-12-centos:/mqtt>tree
.
|-- aclfile    # 访问控制文件
|-- log        # 日志文件目录
|   `-- mosquitto.log
|-- mosquitto  # mqtt运行目录
|   |-- mosquitto.db
|   `-- pid.pid
|-- mosquitto.conf #配置文件!!!IMPORTANT
`-- pwfile # 用户的密码文件
#cat aclfile
===========================================================
# This affects access control for clients with no username.
topic read $SYS/## This only affects clients with username "roger".
user roger
topic foo/bar# This affects all clients.
pattern write $SYS/broker/connection/%c/state# Add 20210722
user ccnet
topic read ccnet/#
topic write ccnet/#
=========================================================# 创建用户密码文件pwfile
touch pwfile
mosquitto_passwd pwfile user#cat mosquitto.conf |grep -v "#"
=========================================================
pid_file /home/release/soft/mqtt/mosquitto/pid.pid
user release
port 1883
listener 9001
protocol websockets
bind_interface eth0
persistence true
persistence_location /home/release/soft/mqtt/mosquitto
allow_anonymous false
password_file /home/release/soft/mqtt/pwfile
acl_file  /home/release/soft/mqtt/aclfile 

运行Mosquitto

mosquitto -c mosquitto.conf -d

MQTT有很多实现,Mosquitto的魅力在于小而美。有很多开源的实现,基于nodejs、java等,也有商业版本的,更有一些云服务商直接将之PaaS化了。

MQTT:用Mosquitto搭建轻量级的设备接入网关相关推荐

  1. MQTT | Windows + mosquitto搭建MQTT Broker(本地服务器)与MQTTX客户端联调

    文章目录 一.前言 二.mosquitto 2.1.安装 2.2.修改mosquitto.conf配置文件 2.2.1.listener 2.2.2.allow_anonymous 2.2.3.pas ...

  2. MQTT服务器 Mosquitto的部署和应用

    MQTT服务器Mosquitto的部署和应用 MQTT相关介绍请点击 项目目的 利用MQTT协议实现信号远程监控. 传感器->信号收集->lora网关->服务器->客户端 应用 ...

  3. 基于HT for Web 快速搭建3D机房设备面板

    以真实设备为模型,搭建出设备面板,并实时获取设备运行参数,显示在设备面板上,这相比于纯数值的设备监控系统显得更加生动直观.今天我们就在HT for Web的3D技术上完成设备面板的搭建. 我们今天模拟 ...

  4. [转载]CentOS6nbsp;快速搭建轻量级远程桌面nbsp;Xfcenb

    原文地址:CentOS6 快速搭建轻量级远程桌面 Xfce & VNC & Firefox作者:哈囉健一 0.系统信息 CentOS Linux release 6.0 (Final) ...

  5. MQTT通信架构 搭建MQTT服务器

    MQ 遥测传输 (MQTT) 是基于代理的发布/订阅的消息传输协议. 传输屏蔽消息内容 TCP/IP有连接传输(可靠) 小型传输,开销很小,降低网络流量 使用lastwill等机制告知客户端异常中断( ...

  6. MQTT服务器Mosquitto 2.x编译安装配置

    陈拓 2021/04/09-2021/04/15 1. 概述 在<树莓派安装Mosquitto MQTT服务> https://zhuanlan.zhihu.com/p/359395794 ...

  7. esotalk 轻松搭建轻量级bbs

    esotalk搭建轻量级bbs 对于80后,对于论坛还是比较有情怀的,尤其是在返回家乡后,和外界沟通的渠道往往是头条.推酷.ifeng等新闻客户端,尤其是v2,经常上去逛一些东西,可是总感觉少了点什么 ...

  8. 从零开始搭建4G DTU设备对应的云平台(一)

    一.了解通信方式 搭建4G DTU设备对应的云平台过程中第一个问题就是,如何在自己的服务器上面与设备进行通信. 刚开始的时候,我看到说明书上写着TCP协议,还以为是用HTTP协议,用RequestHe ...

  9. 搭建轻量级的容器管理平台-Humpback

    什么是 Humpback? Humpback 可以帮助企业快速搭建轻量级的 Docker 容器云管理平台,若将你的 Docker 主机接入到 Humpback 平台中,就能够为你带来更快捷稳定的容器操 ...

最新文章

  1. Missing separate debuginfos, use: debuginfo-install glibc-2.12-1.107.el6.i686
  2. Kotlin on Android 开发环境介绍
  3. 10.2.4 练习题
  4. 传Facebook将推出应用中心挑战谷歌搜索地位
  5. tomcat(20)基于JMX的管理
  6. mybatis 二级缓存失效_二级缓存updateBatchById失效
  7. BZip2Codec压缩、Map端压缩控制、Reduce端压缩控制……都在这份Hadoop整合压缩知识点里了!...
  8. C语言根据用户输入的3个顶点,【if 语句】根据用户的输入 3 个顶点坐标计算三角形的面积和周长,如果不能构成三角形提示错误....
  9. CSDN开发者周刊 TDengine:专为物联网订制的大数据平台 YugaByte DB:高性能的分布式ACID事务数据库
  10. 腾讯疯狂扩展7000人!我居然挂在了项目这块。。。
  11. leetcode -- 36.有效的数独
  12. PyTorch安装问题解决
  13. java 注册监听_java注册监听模型
  14. C#窗体控件-列表框控件ListBox
  15. 西瓜书——支持向量机
  16. 移动web适配的方式
  17. 试试看:把电脑时间调到2099年12月31号之后,会发生什么
  18. 远程文件包含 php,php本地及远程文件包含漏洞
  19. 时光飞逝,思考,实践,伴我一生的经验
  20. 小博老师解析Java核心技术点 ——表单令牌(一)

热门文章

  1. 浙江省职业技能考试大纲计算机,最新修订浙江省高校招生职业技能考试大纲-计算机类...
  2. 工具篇---Node.js的安装和配置
  3. 简诉android源代码编译过程,Android源码编译过程及原理(二)
  4. 2021年第二届“大湾区杯”粤港澳金融建模竞赛B题解题思路和部分代码
  5. 中国计算机专业创始人,无怨无悔来时路――访计算机专业创始人吴忠明校友
  6. 深度Linux设置中文,Linux Deepin 12.12.1配置指南
  7. QML中的组件——QML
  8. 嵌入式linux如何学?
  9. K9无线充电5W无线快充pcba方案FS68001
  10. 一文搞懂数据质量怎么做,很接地气!