The OOKLA portal speedtest.net has been popular among masses for ages and is ideal to measure your internet bandwidth. But, what about the private enterprise network circuits, where traffic remains within an MPLS cloud and doesn’t break out of ISP perimeter. iPerf serves this very purpose of measuring the throughput of an Ethernet circuit bounded within an MPLS cloud. There are many alternatives to iPerf; for eg: jPerf, trex, netperf are some other alternatives. For this post, we’ll focus on iPerf, precisely iPerf3.

iPerf is a CLI based client-server program which generates either TCP or UDP traffic to test the…


Above is a Cisco 7604 router which has had the privilege to be the provider edge for many ISPs across the globe. Before the advent of Cisco ASRs, Cisco 7000 series routers have kept the internet running for past 15 to 20 years and essentially these routers possess the same architecture as that of access point in your home. It consists of 3 components:

  • Control Plane Module
  • I/O Module
  • Switch Fabric

I/O Module and Control Plane Module are both pluggable modules in this case and are interconnected to each other. …


In the course of network troubleshooting, many a times you must have encountered this intriguing ping response: U.U.U. We all know that the dot signifies that a response was not received before the request timed out, while the U indicates that destination unreachable message was received from router somewhere along the path. But why do these responses appear in an alternating pattern? The answer to this question lies in how a router performs ICMP rate limiting.

Rate limiting is configured to control the amount of various outgoing traffic from a network, usually by an ISP to throttle the BW usage…


‘Archive’ is an underrated feature of Cisco IOS/IOS-XE present since IOS 12.4(20)T. It enables you to take a snapshot of a configuration just like the ‘Checkpoint’ Feature on Cisco NX-OS and allows you to store it as an archive file. Ideally these archives can be stored in the root directory of Flash memory on a Cisco IOS device.

By default, the router can store 10 archives. Command maximum <1–14> can be used either to restrict the number of archives or configure it to max limit which is 14. …


The 2020 Black Swan is going to change the World, period! The NEW WORLD ORDER is imminent, and mankind will have to adapt to all the “new normal”. A change we all anticipate like any other major change isn’t going to be without severe damages, of which few have already been experienced across various sectors of our society. Travel Industry albeit among the worst hit and perhaps also among the ones to experience slowest recovery could experience a boost in Sustainable & Responsible Travel. Fellow Travellers, this is our best shot at making responsible tourism a global mandate.

On a…


When it comes to India, it is very hard to pick out just one place that you absolutely must see. I can chat and keep rambling about the places that are amazing, but not quite as amazing, and the places that are really and truly amazing. By the end of it you would realize that India is a country best traveled by living here. But let’s get practical and try to jot down a “perfect” 2 week itinerary covering as much as possible.

Planning your Trip to India

Narrow it down. India is HUGE and if you try to squeeze too much in, you will…

Harsh Joshi

A Traveller at Heart, Network Engineer by Choice

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store