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Speed tests differ from Xfinity to Speedtest.net??

New Poster

Speed tests differ from Xfinity to Speedtest.net??

Can someone explain this? I have Xfinity (cable) internet. (just internet) and at some point during the day my download speed will drop off.. (I'll notice due to streaming glitches to the tv via PS3 wired ethernet) I'll goto the laptop and open the Xfinity speed test site and it'll do the test and return something like 1-2 Mbps up and 1-2 Mbps down.. (says it connects to Jacksonville Fl., Im in Debary Fl.) So I'll immediately go to Speedtest.net and do their test and it'll show normal Down/Up speed.. (ie. 60Mbs/7Mbs)?? I'll go back and forth between Xfinity and Speedtest.net and the results are consistent.. How can I get a normal down/up speed from Speedtest.net, but my actual provider test is slow?? I really wouldn't care if the tests were different, if it weren't for the fact that when Xfinity shows my speed is slow, my speed is "actually" slow.. It clears up in half an hour or so and all is good. But can't figure out how my connection is slow, but if I goto speedtest.net it shows it's fast? I regularly cycle the modem and router via power on/off.. Doesn't seem to help/effect the down/up speeds. If this is a hub, hop or route issue, could a VPN help me? Thanks for any insight.. 

Regular Contributor

Re: Speed tests differ from Xfinity to Speedtest.net??

I would actually think the Xfinity test would be the reverse with the higher results than speedtest.net.  The xifinity test should be giving you the most optimal short 2-5 hops to their internal test server w/o dealing with a whole lot of routing across the real world traffic.  If you have some specific things like netflix then try their speedtest @ fast.com that will test directly to their servers.  If you want something a little more unbiased try http://www.dslreports.com/speedtest or you can even download the speedtest app http://www.speedtest.net/apps/desktop .  

 

As to the 1/2 hour of slow speeds it concerns me that you might have a signal issue or fluctuation that's causing us/ds channels to drop causing the slower speeds.  If you could login to the modem http://10.0.0.1 or http://192.168.100.1 and provide them just in case it's a signal issue it might be helpful in narrowing it down even further.

 

Sometimes doing a traceroute to some destinations will also pick up on where the issue lies as well.  Usually picking a couple of sites like google or yahoo will show you the path that your traffic is taking and potential hops that are having congestion issues.

Contributor

Re: Speed tests differ from Xfinity to Speedtest.net??

 

I also live in Debary also and get slowdown at times but not anywhere as bad as that. I have Comcast Blast that they just upgraded to 100 Mbps. I tried both of those test sites and got 115 Mbps on Comcast and 119 Mbps on the Speedtest.net.

 

I would suggest you connect your computer directly to the Modem bypassing the router via cable and run the tests. It will help to determine if it is a router or a modem issue. If the speeds are still slow, first check to see if your modem is on the supported list (http://mydeviceinfo.comcast.net/). I replaced mine last year as it was on the “end of life” list and then went unsupported. Next I would try to reset the modem to factory settings if you can and retest. Then the next step would be to contact Comcast. If you need to replace the Modem, I suggest that you get one of the higher performing ones.

 

I also like separate modems and routers.

 

If the speeds are fine than you need to trouble shoot the Router.

 

Hope this helps. 

New Poster

Re: Speed tests differ from Xfinity to Speedtest.net??

Thanks for the replies! I'll have to dig up my paperwork on the cable modem. Looks like I have a Motorola JRSB6121 and it's on the no longer supported list.. (and an TP-Link 300gb router) <--- also dated.. 

 

I agree on the speeds "should" be swapped, when comparing Xfinity and Speedtest.net.. (I've also tried other speed sites when this happens (m-lab), just couldn't recall their name when I posted this) and the results are similar to Speedtest.net.. BUT, when everything is working fine, Xfinity and these other speed sites report similar speeds.. It's almost like my route to Jacksonville has a bad hop at times, but not sure how it avoids it when I log into these other speed sites. 

 

Anyway, thanks for the replies! I have a call into Xfinity, but now that I see my modem is no longer supported I doubt they'll be of much help until I upgrade. It's probably time for a new Cable modem and router anyway.. My equipment is more than a few years old.