by Ciro Santilli (@cirosantilli, 34)
To test it, let's get two computers on the same local area network, e.g. connected to Wi-Fi on the same home modem router.
On computer B:
On computer A, run on terminal 1: 
sudo tcpdump ip src 192.168.1.102 or dst 192.168.1.102
Then on terminal 2 make a test request: 
curl 192.168.1.102:8000
Output on terminal 1: 
17:14:22.017001 IP ciro-p14s.55798 > 192.168.1.102.8000: Flags [S], seq 2563867413, win 64240, options [mss 1460,sackOK,TS val 303966323 ecr 0,nop,wscale 7], length 0
17:14:22.073957 IP 192.168.1.102.8000 > ciro-p14s.55798: Flags [S.], seq 1371418143, ack 2563867414, win 65160, options [mss 1460,sackOK,TS val 171832817 ecr 303966323,nop,wscale 7], length 0
17:14:22.074002 IP ciro-p14s.55798 > 192.168.1.102.8000: Flags [.], ack 1, win 502, options [nop,nop,TS val 303966380 ecr 171832817], length 0
17:14:22.074195 IP ciro-p14s.55798 > 192.168.1.102.8000: Flags [P.], seq 1:82, ack 1, win 502, options [nop,nop,TS val 303966380 ecr 171832817], length 81
17:14:22.076710 IP 192.168.1.102.8000 > ciro-p14s.55798: Flags [P.], seq 1:80, ack 1, win 510, options [nop,nop,TS val 171832821 ecr 303966380], length 79
17:14:22.076710 IP 192.168.1.102.8000 > ciro-p14s.55798: Flags [.], ack 82, win 510, options [nop,nop,TS val 171832821 ecr 303966380], length 0
17:14:22.076727 IP ciro-p14s.55798 > 192.168.1.102.8000: Flags [.], ack 80, win 502, options [nop,nop,TS val 303966383 ecr 171832821], length 0
17:14:22.077006 IP ciro-p14s.55798 > 192.168.1.102.8000: Flags [F.], seq 82, ack 80, win 502, options [nop,nop,TS val 303966383 ecr 171832821], length 0
17:14:22.077564 IP 192.168.1.102.8000 > ciro-p14s.55798: Flags [F.], seq 80, ack 82, win 510, options [nop,nop,TS val 171832821 ecr 303966380], length 0
17:14:22.077578 IP ciro-p14s.55798 > 192.168.1.102.8000: Flags [.], ack 81, win 502, options [nop,nop,TS val 303966384 ecr 171832821], length 0
17:14:22.079429 IP 192.168.1.102.8000 > ciro-p14s.55798: Flags [.], ack 83, win 510, options [nop,nop,TS val 171832824 ecr 303966383], length 0
TODO understand them all! Possibly correlate with Wireshark, or use -A option to dump content.
Amazing tool that captures packets and disassembles them. Allows you to click an interactive tree that represents Ethernet, TCP/IP and application layer like HTTP.
Start capture immediately from CLI, capture packets to/from 192.168.1.102: 
sudo wireshark -f 'host 192.168.1.102' -k
Capture by instead: 
sudo wireshark -f http -k
sudo wireshark -f icmp -k
Filter by both protocol and host: 
sudo wireshark -f 'host 192.168.1.102 and icmp' -k
For application layer capture filtering, the best you can do is by port: 
sudo wireshark -f 'tcp port 80'
There is an http filter but only for as a wireshark display filter
Sample usage: 
sudo tshark -f 'host 192.168.1.102
This produces simple one liners for each request.
What you likely want is the -V option which fully disassembles each frame much as you can do in the GUI Wireshark: 
sudo tshark -V -f 'host 192.168.1.102

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