Your cable modem may be used as a hotspot

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Oct 10, 2002
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Yeah I noticed this the other day while looking at Comcast's internet packages, many of them offer "Access to over one million WiFi hotspots at no extra cost." Nice.

No thanks.
 
Few questions/issues...

Since when does a cablemodem broadcast WiFi? In those articles they use the terms cablemodem and router interchangeably as if they don't know what the difference is or don't think there is a difference. I personally own my own modem and I'm pretty sure my Motorola Surfboard modem isn't even capable of doing the stuff they want to do in terms of WiFi. Curious how subscribers like me fit into their scheme. Does this even apply to someone only using a modem, or do you have to be using a full on comcast modem/router combo unit?

If this is a function of the modem, and also applies to users with their own router, wouldn't that seem to imply that those users will now be running a double-NAT? I don't see how a cablemodem could allow WiFi users to connect without employing some sort of internal NAT.

Is this WiFi supposed to be on 2.4Ghz, 5Ghz, or both? 5Ghz wouldn't be so bad but between me and my neighbors, we already have all 3 2.4ghz non-overlapping channels very much in-use. So if it was 2.4Ghz, it would be directly interfering with at least one of our 2.4Ghz wifi networks.

For users operating close to the maximum speed supported by their current modem, is there any way that additional users via wifi wouldn't subtract from their available speed?

What sort of restrictions are going to be in place? Assuming WiFi traffic doesn't count against any monthly limits, it might actually come in handy if you made a point to start using the WiFi for all of your bittorrent downloads, etc.
 
Few questions/issues...

Since when does a cablemodem broadcast WiFi? In those articles they use the terms cablemodem and router interchangeably as if they don't know what the difference is or don't think there is a difference. I personally own my own modem and I'm pretty sure my Motorola Surfboard modem isn't even capable of doing the stuff they want to do in terms of WiFi. Curious how subscribers like me fit into their scheme. Does this even apply to someone only using a modem, or do you have to be using a full on comcast modem/router combo unit?

If this is a function of the modem, and also applies to users with their own router, wouldn't that seem to imply that those users will now be running a double-NAT? I don't see how a cablemodem could allow WiFi users to connect without employing some sort of internal NAT.

Is this WiFi supposed to be on 2.4Ghz, 5Ghz, or both? 5Ghz wouldn't be so bad but between me and my neighbors, we already have all 3 2.4ghz non-overlapping channels very much in-use. So if it was 2.4Ghz, it would be directly interfering with at least one of our 2.4Ghz wifi networks.

For users operating close to the maximum speed supported by their current modem, is there any way that additional users via wifi wouldn't subtract from their available speed?

What sort of restrictions are going to be in place? Assuming WiFi traffic doesn't count against any monthly limits, it might actually come in handy if you made a point to start using the WiFi for all of your bittorrent downloads, etc.

That latest trend of Comcast in my area is to roll out all in one "gateway" devices for residential customers. At my parents house for instance, they have a modem/router all in one device. I've gone in and turned off the wifi numerous times since its been installed.

It use to be that I didn't this all in one device unless they had the triple play service where a phoneline needs tied in.
 
That latest trend of Comcast in my area is to roll out all in one "gateway" devices for residential customers. At my parents house for instance, they have a modem/router all in one device. I've gone in and turned off the wifi numerous times since its been installed.

It use to be that I didn't this all in one device unless they had the triple play service where a phoneline needs tied in.

you need to contact comcast and ask them to put your modem/router in bridge mode. this will disable the router built into the modem and turn off wifi.
 
you need to contact comcast and ask them to put your modem/router in bridge mode. this will disable the router built into the modem and turn off wifi.

Or get a $60 modem and not pay them the $7 or $10 per month to rent it, and put your own firewall/router behind it.
 
Or get a $60 modem and not pay them the $7 or $10 per month to rent it, and put your own firewall/router behind it.

they have you by the balls if you have internet and phone. i dont know where you can buy a phone modem.
 
This is nothing new: BT have been doing it for some years in the UK with BT Fon.
 
they have you by the balls if you have internet and phone. i dont know where you can buy a phone modem.

Just transfer your Comcast phone service to something like Vonage. I've been a Vonage customer for ~10 years now, it's cheap and works great.
 
So where do i send the bill for power usage and space rental on MY property?

There must be a way to sue these guys for something like this in using resources that are not their's with out permission.
 
So where do i send the bill for power usage and space rental on MY property?

There must be a way to sue these guys for something like this in using resources that are not their's with out permission.

No doubt that's all covered legally in the fine print when you accept their services and use their equipment.

There should at least be an opt out clause openly available to all customers.
 
So where do i send the bill for power usage and space rental on MY property?

There must be a way to sue these guys for something like this in using resources that are not their's with out permission.

Comcast putting a Wifi gateway with unknown security in my house/business sounds like fair compensation for modem/device rental fees doesn't it? :rolleyes:

Seriously though, Comcast has been advertising the crap out of this for like 18 months now... Why is this news? Every one of my SMB clients has all asked me about it. Just say no to Xfinity WiFi, ask for a simple modem and call it done.
 
So they stated this will not impact the speeds, but will it count twords the data cap?
 
So they stated this will not impact the speeds, but will it count twords the data cap?


There is no way this cannot affect speeds. Even if you don't notice it, a Wi-Fi hotspot would use your connection from the modem to the coax. They are using statistics (such a wonderful math) to assume you'll never be in a situation where multiple people are using your hotspot when maxing your download.

It's physically impossible to have a all-in-one modem/router combo w/wireless offered as a hotspot not use your connection. They might be able to voodoo magic it so that it doesn't count towards your cap, but seeing how EVERY ISP has fucked up their cap system (it's literally impossible without full DPI technology) nobody believes them.

At the end of the day you are PAYING for a internet connection for your household, NOT for some other asshole to get a free ride. I don't care if they are a Comcast user or not. Even if it works out for both sides since we're all "Comcast" subscribers. It's MY connection. If I want to share my wireless I'll do it myself.

This topic should be deeper.

KILL ALL CABLE MODEM/ROUTER COMBOS! BURN IT WITH FIRE!
 
Comcast claims it shares a specturm but doesn't count against your CAP.
"The second network won't slow your primary connection down, at least not much. "The broadband connection to your home will be unaffected by the XFINITY Wi-Fi feature," Comcast says. "Your in-home Wi-Fi network, as well as XFINITY Wi-Fi, use shared spectrum, and as with any shared medium there can be some impact as more devices share Wi-Fi. We have provisioned the XFINITY Wi-Fi feature to support robust usage, and therefore, we anticipate minimal impact to the in-home Wi-Fi network."

Source:http://arstechnica.com/information-...d-to-learn-new-router-is-also-public-hotspot/

the solutions seems to be call comcast to put your modem in bridge mode. (use your own router/firewall/wifi)
 
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Comcast only does this for business class, at least in my area.

They are trying to create a city hot spot. This info came from my buddies who do business installs.
 
Wow, so they charge you a rental fee to install a device in your house that they sell as a service for other customers to use.... That is so far beyond greed it's ridiculous....

Thank god I bought my own modem the second they tried to charge me the rental fee. They can go F themselves with a pineapple....
 
Comcast turning your home into a public WiFi hotspot

HOUSTON (KTRK) --
Starting today, WiFi access can be found all across the city of Houston, but some people are not too happy about it.

What's wrong with free WIFI? The machines generating it are inside people's homes, and many say they did not know their WiFi routers would host other people too.

Michelle Eulene has been a Comcast customer for years, but she's not happy with her WiFi now that her router is playing host to other Xfinity customers who want an internet connection.

"It feels weird for Comcast to take my modem that I am already paying for and delivering it to other people," said Eulene.

Eulene adds she was surprised to learn Xfinity is allowing WiFi routers in Houston to be an access to the world wide web. It's got Eulene very worried about online privacy and that's not all.

"What if somebody downloads something illegal and then it traces back to me? I didn't do it. So how is that going to work out," asked Eulene.

"That was my concern as well," said Houston IT expert Colman Ryan.

Ryan tested the Wi-Fi routers himself and says the router design does not allow strangers access to a person's data. He adds if someone downloads illegal content it will be the person who logged into the public side of the Wi-Fi router who gets in trouble.

While this may look like the Matrix, Ryan says it shows two separate paths to the internet on the Xfinity WiFi.

"The pathing test that I did, I looked at them side by side and they took completely different networks which is what we want to see," said Ryan.

Comcast says the public feature on the WiFi router is turned on by default, but you can turn it off by calling 1-800-XFINITY or by visiting My Account, clicking on "Users & Preferences", and then selecting "Manage XFINITY WiFi.

Comcast says only 1% of customers have opted to turn off the Home Hotspot feature. The customers we spoke with say they don't like the idea, but not enough to cancel their subscriptions.
 
Run your own modem and it isn't a problem. It's only a problem if you use their phone services. I can only see families with small children doing this.
 
It shares your bandwidth.

The data usage is tracked via MAC address. The Hotspot has its own MAC.

You can turn it off.


Meh.... but they should disclose this feature upfront when you sign up and again when they install your equipment.
 
It likely doesn't even need to share bandwidth. An 8 way bonded DOCSIS 3 modem has almost 400Mbps worth of bandwidth available, even if you pay for 150Mbps that's still almost 250Mbps that your modem could use for guests. The hotspot likely has some other limit, or just limits itself to 802.11g speeds (are any of these combos 802.11n?), and it literally has no effect on you. At least theoretically.
 
It likely doesn't even need to share bandwidth. An 8 way bonded DOCSIS 3 modem has almost 400Mbps worth of bandwidth available, even if you pay for 150Mbps that's still almost 250Mbps that your modem could use for guests. The hotspot likely has some other limit, or just limits itself to 802.11g speeds (are any of these combos 802.11n?), and it literally has no effect on you. At least theoretically.

It affects people in that they are taking something you pay a monthly fee for, and reselling that service again to other people, double dipping the chip kinda thing.
 
It affects people in that they are taking something you pay a monthly fee for, and reselling that service again to other people, double dipping the chip kinda thing.

it's not double dipping, they are offering wifi to existing customers so they can get access in numerous places. If the bandwidth doesn't come out of your bucket and is a separate network, I'd have no issue with it. And it would benefit you when you are out and about and have all these new wifi hotspots to use.
 
Except it's free to existing customers to use when away from home, which, if you're a Comcast customer, is a bonus to you.

Would this be ok if they took out the whole "non customers can buy temp access" thing and only let other paying Comcast customers access?

What if they called you up and said "Sir we'd like to send you a device to plug into your network, this device would provide wifi service to Comcast customers (both permanent and temporary). This device will be provided at no charge, would in no way count toward your monthly bandwidth, not interfere with your download speeds, and in return we'll give you free access to this wifi network for you to use when away from home." Would that be better?

Lets look at the pro's, neutral's, and con's here:

Pro:

  • You get free access to wifi networks away from home, and more free wifi is always good. Say you're visiting a friend and want to use wifi on your tablet, you don't even have to ask for his wifi password you can just hook up to the Comcast one.
  • People visiting your home don't need to access your wifi network, they can just use their Comcast login and you don't have to tell them your wifi password is "1lik3b00bi3z".
  • Comcast doesn't require you to reciprocate in order to use the service, you can be as big a dick as you want and say "BUT I DON'T WANNAAAAAAAAA" and they'll still give you access.
Neutral:

  • Presumably not counted toward your bandwidth speed limit.
  • Not counted toward your bandwidth cap.
  • Non Comcast customers can access it by paying Comcast a small fee.
Con:

  • Enabling wifi on the cable modem, if you're using you own wifi, might use a few extra watts of power adding up to several cents more on your power bill each year.
Yeah I included them maybe making a few bucks off your connection under neutral because that fact in no way negatively impacts you or your use of the service you pay for unless you happen to be a whiny little bitch, because really who cares.

So two pretty big pro's and one minor one, the third pro is probably particularly pertinent to your interests, handful of neutrals that impact you in no way what so ever, and one con that will mean you might have to give up a can of soda over the next 3 years.

What exactly is the problem here? This honestly sounds like a win/win to me.
 
It's not the obvious pros/cons list in my mind. I'm more worried about potential exploits against the devices themselves and/or security logging.

1) What I haven't seen answered, is that will the "Comcast WiFi" have a different Public IP? If so, what's the stop someone from "borrowing" credentials for nefarious purposes? And/or sharing their credentials with friends?

2) Exploits against the devices themselves. Several Home grade routers have already been cracked open. What happens when the router that milions of subscribers use gets cracked and access to the internal networks is exposed? It's a possibility to consider. Most of us here, being more technically inclined, will either use our own/old cable modem or use another router behind their WiFi gateway. But the masses could be exposed. And I already get enough calls from family :)
 
Comcast turning your home into a public WiFi hotspot
"What if somebody downloads something illegal and then it traces back to me? I didn't do it. So how is that going to work out," asked Eulene.

"That was my concern as well," said Houston IT expert Colman Ryan.

Ryan tested the Wi-Fi routers himself and says the router design does not allow strangers access to a person's data. He adds if someone downloads illegal content it will be the person who logged into the public side of the Wi-Fi router who gets in trouble.

While this may look like the Matrix, Ryan says it shows two separate paths to the internet on the Xfinity WiFi.

"The pathing test that I did, I looked at them side by side and they took completely different networks which is what we want to see," said Ryan.

1a) It was answered, see above
1b) Probably the same things preventing them from "borrowing" your bank, online store, other streaming service credentials and using them for nefarious purposes i.e. nothing.
2) Just because something could possibly be exploited isn't a reason to not do it. If you follow this line of thinking to it's conclusion we should just turn off the internet, forbid all communications between people, or at the very least just freeze everything where it is and forbid any further progress to eliminate the possibility of adding any more exploits. Lets face it con man is the worlds 3rd oldest profession after prostitute and pimp.
 
I took my rental in the other day, and in no uncertain terms told them to stick it up their asses. I had an old cable modem (Still docsis 3) laying around, so I'm using that for now.
 
Just transfer your Comcast phone service to something like Vonage. I've been a Vonage customer for ~10 years now, it's cheap and works great.
Was a Vonage customer since they first started service, one of the first customers. Was good, but there's better competition now like magicjack and ooma.
 
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