Packet loss in Win7/vista but not Xp

Hello,

Just curious if anyone has noticed packet loss in Vista/Win7 systems which is not present in WinXp.

I have tested this on both Comcast and Brighthouse residential internet connections. Two different intel i920 based computers, one with onboard Marvell NIC and the other with onboard Realtek 8111C NIC, both with dual boot configuration, and both connecting to the internet via motorola surfboard cable modems and Dlink DGL-4500 or Dir-655 routers. I even added an intel pci express NIC to one of the systems and using the intel (gigabit CT) NIC, the results are the same. I tried doing a safe mode boot with networking and the results are also the same.

Results:
Both computers running under XP experience 0% dropped packets when using ping test easy (Ping Test Easy - Free software downloads and software reviews - CNET Download.com). I ping www.Google.com with default settings (ping rate of 1 ping every 0.6 seconds and time out threshold of 500ms). Even if left to run for hours, there is 0% packet loss, or rarely if left running long enough, a max of 0.2% loss.

Both computers running under Win 7 (64 bit) pinging google with the same parameters will invariably show around 6-8% packet loss. The dropped packets will show up pretty quickly at the default ping rate.

Interestingly though, my brother has a computer with an onboard realtek 8111D NIC running under win7 pro (64 bit) and his system has 0% packet loss when pinging google with the same parameters. He has comcast internet service with a motorola cable/phone modem and a linksys router.

Has anyone else observed this packet loss with Win7/Vista systems? Anyone running Win7 or Vista systems want to do some pinging and report back???

Thanks for any input on these observations.

Thanks for the quick reply!

OK, I'll try it when I leave work and report back. Just curious- what info will this method of pinging give you?

Hi Dinesh,

I'm going to be at work for a while, so I had my girlfriend run a few tests on one of the computers with Windows 7.

Using ping tester easy at default settings, there was about a 4% packet loss when pinging google (I had her try a couple of runs of 200 pings).

Under the command prompt, pinging google yielded 0% loss (4 sent, 4 received). But if I had her ping google with a 500ms timeout (duplicating the settings in ping tester), there was about a 2% loss (I had her ping google under the command prompt with a 500ms timeout parameter- several runs of 100 pings each yielded between 1 and 4 packets that were sent but not received). When I had her run a few runs of 100 pings with the default (1 sec) timeout, there was almost always 0% loss (I think one run yielded 1 lost packet out of 100).

I had her try the same tests with a winXp laptop on the same connection, and all the tests mentioned above yielded 0% lost packets.

So is a 500ms time out threshold just too "tight" to be meaningful in real world apps? I discussed this on another forum and the thought was the win7/vista network stack had inherent latency compared to the XP stack, but was of no significant consequence,

However, this doesn't explain why some Win7 systems have no packet loss under the above testing parameters. Are some NIC's (the realtek 8111D for example) just more optimized for win7/vista?

Thanks for your input.

Suggest you check with the manufacturer of your network card for the very latest driver for your operating system.

If after install of very latest driver the problem still exists, the use MSCONFIG then disable absolutely all programs which you don't really need to start at start time from running at startup time.