ptp-jitter.py

#!/usr/bin/env python3

import scapy.all
import sys

last_sync = 0
m = 9999
M = 0

length = 272

def pkt_callback(pkt):
    global last_sync, m, M
    data = bytes(pkt.payload.payload.payload)

    if data[0] == 0x00:
        last_sync = pkt.time
    if data[0] == 0x08:
        if last_sync == 0:
            return
        bars = int((pkt.time - last_sync) * 1000 * 1000)
        lat = bars/10
        if lat < m:
            m = lat
        if lat > M:
            M = lat
        stats =  "min: %5.1f max: %5.1f cur: %5.1f" % (m, M, lat)
        if bars > (length-len(stats)-1):
            bars = (length-len(stats)-3) * "#" + ">>"
        else:
            bars = bars * "#" + (length - bars - len(stats) - 1) * "."
        sys.stdout.write("\r" + bars + " " + stats)
        sys.stdout.flush()
scapy.all.sniff(iface="enp0s20f0u3", prn=pkt_callback, filter="udp and (port 319 or port 320)", store=0)