Comcast Is Cheating People On Monthly Data Usage!

[newtekie1]

Every month I get the alert from Comcast that I've used 90% of the the 1TB data limit on my internet. I know I use a lot of data, but I didn't think I was using 1TB that quickly. So I installed a router that tracks bandwidth usage and let it run for a few months. The results are interesting.

This is my monthly data usage according to Comcast:

And this is my monthly bandwidth usage according to my router:

This is the break down of daily bandwidth usage for January:

Every single month since I installed the router and started tracking my actual data usage, Comcast has said I've used more data than I actually have. This month is the worst, they are saying I've used 160GB+ more data than I actually have.

So I just wanted to give a heads up to people that Comcast hits with monthly overages.

 

[Aquinus]

Is it possible that the extra is traffic being blocked by your firewall? When I was running a gateway server there was actually a good amount of traffic that my firewall was blocking and since it's blocked after it gets through the cable modem, that traffic would be counted on their end, but it won't be counted on your end if it's only accepted packets being counted.

I'm not saying that's okay, but it could be a possible reason why the numbers are substantially different. I'm also assuming your gateway is the only device connected to the modem.

 

[newtekie1]

Is it possible that the extra is traffic being blocked by your firewall? When I was running a gateway server there was actually a good amount of traffic that my firewall was blocking and since it's blocked after it gets through the cable modem, that traffic would be counted on their end, but it won't be counted on your end if it's only accepted packets being counted.

I'm not saying that's okay, but it could be a possible reason why the numbers are substantially different. I'm also assuming your gateway is the only device connected to the modem.

I'm not going to say it is impossible, but not likely. Also, I think that data would still be counted, as it still travels over the WAN port on the router that is being monitored, it just isn't allowed to travel through to the LAN side.

 

[Aquinus]

I'm not going to say it is impossible, but not likely. Also, I think that data would still be counted, as it still travels over the WAN port on the router that is being monitored, it just isn't allowed to travel through to the LAN side.

That's not how it worked on my gateway server. My firewall would block traffic on the input iptables chain on the WAN interface and would never make it to the input or forward chain on any of the LAN interfaces. If it was already an established connection, only then would it get blocked on the forward chain on the wan interface.

All I'm saying is that it depends on how iptables is configured if it's a linux based router. I would tend to agree with you though that it seems unlikely since >100GB of unaccounted bandwidth is highly suspicious.

This tempts me to setup a gateway server again though because the numbers I'm seeing from Comcast seem a little inflated on my end as well, I just don't have anything to check it against.

 

[Easy Rhino]

Any chance one device is measuring in KiB and Comcast is measuring KB ?

https://xkcd.com/394/

 

[hat]

Aren't KiB and KB (not Kb) the same?

 

[Mr.Scott]

Not surprised. Spectrum does the same thing.

 

[Bill_Bright]

There will always be some "handshaking" "overhead" going on between the modem and the ISP. This will be data exchanges that do not go through the router. IMO, that should not be counted against the customer. But since most (probably all) ISPs will always put profit over doing what's right for the customer, Comcast could be counting that overhead traffic against you too.

Not sure how you could determine that without unplugging your router (your entire network) from your modem for 1 month and then see what they are counting against you. Can you go "off the grid" for a whole month? Can you track what Comcast is reporting in 24 hour increments instead of a whole month at a time?

Aren't KiB and KB (not Kb) the same?

No. It is the same thing as happens with hard drives where, depending on who you talk to, 1 kilo is 1000 or 1 kilo is 1024. In pure mathematics and science, 1 kilo = 1000. In data and data storage, 1 kilo (or in this case 1 KiB) = 1024.

@newtekie1 - you need to research how your router counts bits. Looking at your screen shot and the note at the bottom, it would seem Comcast uses 1024 = 1K. Ummm, nevermind! In thinking about this, if your router used 1000, your router logs would show higher numbers so, assuming Comcast uses 1024, it is not that. So I am back to the modem's overhead issue, or Comcast is just flagrantly cheating. I doubt that as there are just too many watchdogs out there for them to risk intentional criminal activities.

 

[dorsetknob]

Guest Wi-fi hotspot traffic ?
They Claim that OTHER CUSTOMERS use of Wi-Fi Hotspots do Not use your Bandwidth and your not Charged

worth checking router settings (and a wi-fi Sniffer )

 

[Aquinus]

Guest Wi-fi hotspot traffic ?
They Claim that OTHER CUSTOMERS use of Wi-Fi Hotspots do Not use your Bandwidth and your not Charged

worth checking router settings (and a wi-fi Sniffer )

This actually is an excellent point. Now that I think about it, I remember this thread that @newtekie1 made. Perhaps it's possible that this traffic is actually metered against you?

 

[Bill_Bright]

Guest Wi-fi hotspot traffic ?

Thought of that too. But as noted, that traffic does not (or is not supposed to) count against your limits.

 

[Aquinus]

Thought of that too. But as noted, that traffic does not (or is not supposed to) count against your limits.

I wonder if Comcast explicitly calls out how bandwidth gets monitored for usage. I feel like they would have some fine print somewhere that would spell all of this out. This is the only thing I've been able to find so far and the only things it says it doesn't include is TV and Voice plans and that anything, regardless of source, is counted. The verbiage seems to indicate that everything is counted. It also seems to be the case the the list of states for which the Terabyte cap is enforced doesn't include NH which I find intriguing. Not sure if I want to test that though.

 

[Readlight]

Looks like 50 GB game and highy quality movie download user. why wired internet haw data limit? i get for 2 euro unlimited slow mobile internet free sms and voie calls. and if i want optic i drive to other home.

 

[natr0n]

Watch youtube in 720p so you can lower your data usage.

It works.

Also....ARRRRRR

 

[qubit]

I've noticed how the ISPs measurements are consistently more than what I measure when I used to compare them, but these differences seem way too large to be a reasonable margin of error.

Having tried telling them about it and seeing what response you get? Even if it's a fob-off, you can sometimes still glean something from it.

 

[dorsetknob]

why wired internet haw data limit? i get for 2 euro unlimited slow mobile internet free sms and voie calls. and if i want optic i drive to other home.

This thread is not what you claim to get for 2 euro's ( which i do not ******) but what Comcast bill and deliver

 

[Bill_Bright]

I wonder if Comcast explicitly calls out how bandwidth gets monitored for usage.

They do, but the consumer finding it may be a challenge.

See this ars Technica article and note the following:

Will the homeowner be accountable for visitors' data usage via the XFINITY WiFi Home Hotspot on the homeowner's wireless gateway?

No. The data usage of visiting users (over the xfinitywifi network signals) is tied back to the visitors' accounts, not the homeowner's. Homeowner's activities and data usage on the Home Hotspot are tied to the homeowner's account.

Does XFINITY WiFi hotspot usage count towards the customer's data plan?

Not currently, Data usage via XFINITY WiFi and Cable WiFi hotspots (over the xfinitywifi or cablewifi network signals) does not currently count towards the customer's XFINITY Internet data plan.

Now the phrase I find troublesome is "Not currently".

 

[Static~Charge]

Aren't KiB and KB (not Kb) the same?

No. It is the same thing as happens with hard drives where, depending on who you talk to, 1 kilo is 1000 or 1 kilo is 1024. In pure mathematics and science, 1 kilo = 1000. In data and data storage, 1 kilo (or in this case 1 KiB) = 1024.

When you're talking about computer storage/memory/data transmission, KB and KiB are the same thing:

"1 KB" means 1024 bytes (as Windows would report it, traditional usage)
"1 kB" means 1000 bytes (as Mac OS would report it, IEC usage)
"1 KiB" means 1024 bytes (unambiguous, but perhaps unfamiliar terminology)

Files size units: "KiB" vs "KB" vs "kB"
https://ux.stackexchange.com/questions/13815/files-size-units-kib-vs-kb-vs-kb

 

[newtekie1]

This actually is an excellent point. Now that I think about it, I remember this thread that @newtekie1 made. Perhaps it's possible that this traffic is actually metered against you?

Thought of that too. But as noted, that traffic does not (or is not supposed to) count against your limits.

Even if that was the case, I haven't used the Xfinity Hot Spots this month, other than maybe my phone connecting from time to time when I'm way from home, but I can't see my phone using 160GB+ of data.

 

[Bill_Bright]

Even if that was the case, I haven't used the Xfinity Hot Spots this month, other than maybe my phone connecting from time to time when I'm way from home, but I can't see my phone using 160GB+ of data.

Not a Comcast customer so I have never used them. But it seems to me this type usage should be a separate line entry on your bill (or in an app on your phone) so you could see the breakdown of your charges - kinda like "roaming" charges used to be (and may still be in some areas) listed separately.

KB and KiB are the same thing:

Except they aren't - at least not consistently. Look at your own reference. What the heck is kB anyway? To Apple it is 1000 and to others 1024? That's nonsense.

For sure, it should be consistent, but sadly, companies seem to do what they want. And to your comment about "storage" specifically, hard drive makers were often the biggest offenders! Why? Because by using 1000 instead of 1024, they could market their drives as larger than they really were.

The problem is, of course, if the company uses the decimal system or binary. Decimal is 1000, binary 1024.

Did you know CD capacities were measured in binary while DVD capacities were in binary?

 

[Aquinus]

Even if that was the case, I haven't used the Xfinity Hot Spots this month, other than maybe my phone connecting from time to time when I'm way from home, but I can't see my phone using 160GB+ of data.

What about late last month? I suspect when they say "January" or "December" that they're talking about billing months, not real months. The month probably represents the month that the bill was created in. Having worked with systems that do time-based billing for reporting purposes, it makes a ton of sense if Comcast did it this way.

 

[Easy Rhino]

Aren't KiB and KB (not Kb) the same?

Yup, they are different. Not sure if Comcast says exactly how they are measuring. Also, as noted in another post, I wonder if @newtekie1 's router is only measuring payload and not headers?

 

[FordGT90Concept]

Yup, they are different. Not sure if Comcast says exactly how they are measuring. Also, as noted in another post, I wonder if @newtekie1 's router is only measuring payload and not headers?

This. Comcast is likely counting the entire size of every packet where router is only counting packet payload.


As also mentioned, there could be a GB vs GiB thing going on. Comcast's figures are most likely GB (billion bytes) but the router might be GiB (2^30 bytes).
965.77 GiB = 1,036,987,641,364.48 bytes

They also might not be counting the same packet types (e.g. pings) against bandwidth.

Comcast might not be counting lost packets (how could it?) which is why your router, assuming it's GiB, is higher than Comcast's GB figures.

If your WAN port is connected to a hardware device before reaching Comcast's network, it's possible that you're seeing some packets related to communication between the two devices that don't reach Comcast's figures (they're still intranet).

 

[Easy Rhino]

This. Comcast is likely counting the entire size of every packet where router is only counting packet payload.


As also mentioned, there could be a GB vs GiB thing going on. Comcast's figures are most likely GB (billion bytes) but the router might be GiB (2^30 bytes).
965.77 GiB = 1,036,987,641,364.48 bytes


They also might not be counting the same packet types (e.g. pings) against bandwidth.

Can anyone find anything official on how they measure???

 

[FordGT90Concept]

It would be in the service contract legalese. Networks almost always go by decimal system though because binary units really have no use in network transmissions. I assume his router is using some flavor of Linux which loves binary units.