A journey of
a single request
Bartosz Legięć
Frontend developer @ Netguru

@bibix1999

legiec.io
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Manchester code
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100 ns = \tfrac{1}{10,000,000} s
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ä
T
Preamble
 
Frame delimiter
 
MAC destinaiton
 
MAC source
 
7 octets
 
1 octet
 
6 octets
 
6 octets
 
Ethertype
 
Payload
 
Frame check sequence
 
Interpacket gap
 
2 octets
 
46-1500 ocetets
 
4 octets
 
12 octets
 
Preamble
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Frame delimeter
Data
Preamble
 
Frame delimiter
 
MAC destinaiton
 
MAC source
 
7 octets
 
1 octet
 
6 octets
 
6 octets
 
💻
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A
B
Internet Protocol
IP
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A
B
192.168.9.2
192.131.9.2
10.0.5.2
10.0.5.3
10.0.5.4
10.0.6.7
10.0.6.10
10.0.6.11
10.0.5.5
10.0.6.13
192.131.0.0/16   > to 10.0.5.4 via em2.0
192.168.9.1/32   > Local via em1.0
10.0.6.0/24      > to 10.0.5.5 via em3.0
192.168.9.0/24   > to 10.0.5.4 via em1.0
192.131.9.0/24   > to 10.0.6.7 via em2.0
10.0.6.0/24      > to 10.0.6.7 via em3.0
192.168.9.0/24   > to 10.0.6.11 via em2.0
192.131.9.0/24   > Direct via em3.0
10.0.5.0/24      > to 10.0.6.11 via em2.0
Ethertype
 
Payload
 
Frame check sequence
 
Interpacket gap
 
2 octets
 
46-1500 ocetets
 
4 octets
 
12 octets
 
Options
Header Checksum
Source IP Address
TTL
Flags
Fragment offset
Identification
Packet Length
ECN
DSCP
IHL
Version
.
.
6
5
4
3
2
1
Destination IP Address
Protocol
Ethernet frame
IP packet
Options
Header Checksum
Source IP Address
TTL
Flags
Fragment offset
Identification
Packet Length
ECN
DSCP
IHL
Version
.
.
6
5
4
3
2
1
Destination IP Address
Protocol

👨‍💻

Root
server
TLD
Server
Authoritative
server
DNS
resolver
Hosting
server
.
.com
warsawjs
warsawjs
.com
.
TCP
SYN
SYN, ACK
ACK
22 bytes of data
ACK
FIN
ACK
FIN
ACK
seq=0
seq=0, ack=1
ack=1
seq=1
ack=23
seq=23
seq=24
seq=1
ack=2
Connection
established
CLIENT
SERVER
Ethernet frame
IP packet
TCP segment
HTTP
{"username":"xyz","password":"xyz"}

POST / HTTP/1.1

Host: example.com
User-Agent: curl/7.64.1
Accept: */*
Content-Type: application/json
Content-Length: 35

{"username":"xyz","password":"xyz"}

Host: example.com
User-Agent: curl/7.64.1
Accept: */*
Content-Type: application/json
Content-Length: 35

POST / HTTP/1.1

HTTP/1.1 200 OK

Content-Type: application/json
Content-Length: 35

{"user":{"login": "xyz"}}

{"user":{"login": "xyz"}}

Content-Type: application/json
Content-Length: 35

HTTP/1.1 200 OK

Thank you
https://slides.legiec.io/a-journey-of-a-single-request