Hi Josselin,

Packet loss can occur anywhere along the path between your computer and the destination you are trying to reach over the Internet.

Packet loss is typically a result of one or more of the following: network congestion, overworked routers and switches, slow roundtrip times, or possibly a result of traffic prioritization schemes used by service providers or the company hosting the site you are trying to access.

Ping measures the roundtrip time between your computer and the IP address you are pinging. Trace route measures the response times of the routers along the path between your computer and the IP address you are trace routing.

You can measure them using the below methods:

Method 1: Using ping for a packet loss test

The best way to measure packet loss using ping is to send a large number of pings to an IP address, and then look for failed responses to those pings.
For instance, if you ping something 50 times in a rapid fashion, you can measure the number of failed responses and use this as an estimate of "packet loss." Anything over five percent is probably something to be concerned about.

This is the command you need to type in cmd:

Ping -n 50 (IP Address or domain name [www.website.com])>

The "–n" tells ping to send a set number of pings, and "50" is the number to send.

Afterwards, you will get a summary of the packet loss test that includes the number lost and a percentage:

If you see a very high average roundtrip time (greater then 100ms), this will also cause you to experience slow network downloads.

Method 2:
Trace routes can be run by using the trace route command at the Windows command prompt.
While the output doesn't show you packet loss, it will show you if there are slow-responding routers along the path.

The output will show you the response time of all the routers. The following is an example:

1. 5 ms 2 ms 3 ms malibu.domain.com [10.10.0.1]
2. 10 ms 6 ms 7 ms 10.60.0.6
3. 9 ms 7 ms 7 ms 10.20.0.1
4. 6 ms 7 ms 7 ms x130.cd9e68.sj.concentric.net [205.158.104.130]
5. 7 ms 7 ms 8 ms ge9-0.dcr2.dc-fremont-ca.us.xo.net [205.158.60.169]
6. 7 ms 7 ms 7 ms ge2-0.dcr1.dc-fremont-ca.us.xo.net [65.106.2.205]
7. 10 ms 7 ms 8 ms p5-1-0-2.rar2.sanjose-ca.us.xo.net [65.106.2.153]

If you see trace route roundtrip times along the path greater than 100ms (1/10th of a second), this can cause slow transfer times over the network.

The best place to start with a packet loss test is to make sure that there is not packet loss between yourself and your service provider.

I hope this helps.

Regards,
Lokesh