Cross-border connection speed

Recently, I started to notice massive slowdown in connection speeds between me (Samara) and German, French, Dutch servers.

This happens in the evening (UTC +4), when people in European Russia use internet more actively.

During slowdowns, speedtest and iperf show slow connection speeds to a variety of European servers (although, sometimes iperf speed are OK). Some websites become less useful.

I decided to write a crude test script to confirm the hypothesis on correlation between slowdowns and MSK-IX traffic volumes. The script downloads a file from my server in Frankfurt and records timings in CSV file.

import argparse
import csv
import datetime

import warnings
warnings.filterwarnings("ignore")

import requests

from time import sleep


parser = argparse.ArgumentParser(prog='Periodic DL perf test', description='Tests network performance by downloading file from specified URL')

parser.add_argument('url')

parser.add_argument('-t', '--interval', help='Interval between tests in minutes (may be float or int)')
parser.add_argument('-o', '--output', default='log.csv', help='Name of the CSV file for test result logging')
parser.add_argument('-i', '--ignore-ssl', action='store_true', help='If set, SSL certificate errors will be ignored')
args = parser.parse_args()

sleep_interval = int(args.interval) * 60

log_file = open(args.output, 'a')

log_writer = csv.writer(log_file, dialect='excel')

while True:
    start = datetime.datetime.now()
    try:
        length = len(requests.get(args.url, verify=(not args.ignore_ssl)).content)
        end = datetime.datetime.now()
        time_taken = (end - start).total_seconds()
        print('Downloaded ' + str(length) + ' bytes in ' + str(time_taken) + ' seconds')
    except:
        time_taken = -1.0
        print("Failed to download file")
        end = datetime.datetime.now()
        length = -1

    log_writer.writerow([start.strftime("%Y-%m-%d %H:%M:%S"), end.strftime("%Y-%m-%d %H:%M:%S"), time_taken, length])
    log_file.flush()
    interval = max(1.0, sleep_interval - time_taken)
    print("Sleeping", interval, "seconds")
    sleep(interval)

After 24h of continuous measurements I plotted graphs in MS Excel:

As you can clearly see, the during during peak traffic periods on MSK-IX average download time rises substantially. In addition, a lot of anomalies happen: download errors and very slow DL speed.

I will perform some other tests in the near future to determine if this slowdowns are caused by bandwidth limits at exchange points or not.