I just had a really bad experience with Comcast support today.
This morning my internet access had become intermittent (but
mostly not working). I could tell right away that something
about the communication between my Linksys router and
Motorola SB4100 cable modem was not right. The "link"
light which is normally solid on the router was blinking
on occasionally, but not staying on.

I did traceroutes between a PC and the modem (through
the router), and a high rate of packet failure was evident.
I swapped the router for another known good one, and
the same behavior occurred. I also swapped cables and
other things. The only thing left was the cable modem.

To really make matters confusing for Comcast, the cable
modem worked fine when connected directly to a PC.
So I spent about an hour on the phone with some tech
support guy named "Mike" in which he insisted over and
over and over that if the cable modem works with a PC
then it is fully functional and is not the problem. WRONG!!!

Since cable modems are cheap now, I decided to run
down to Office Max and get a cheap replacement to
try out. I found a Best Data CMX300 for $60 and
picked that up.

Got home, hooked up the new cable modem, and
presto, everything works fine.

So for the record, it is quite possible for a cable modem
to work fine with a PC but NOT WORK WITH A ROUTER.
I have no idea technically why this can happen, but clearly
it can.

I could hope the paid chimps that work for Comcast would
read this forum, but I assume they don't.

Alan

P.S. We did get competent and friendly help from the Comcast
people who helped us out with the new modem setup. It was
just the moron named "Mike" that is giving Comcast a bad rep.

Some companies tie the account to the PC's MAC address. Therefore you have to clone the MAC
address of the PC to the Router to make the Router work on the cable network.

Dave





"Alan Wright" <alan@yahoo.com> wrote in message news:2audnRZ1rb_gF4_cRVn-gA@giganews.com...
| I just had a really bad experience with Comcast support today.
| This morning my internet access had become intermittent (but
| mostly not working). I could tell right away that something
| about the communication between my Linksys router and
| Motorola SB4100 cable modem was not right. The "link"
| light which is normally solid on the router was blinking
| on occasionally, but not staying on.
|
| I did traceroutes between a PC and the modem (through
| the router), and a high rate of packet failure was evident.
| I swapped the router for another known good one, and
| the same behavior occurred. I also swapped cables and
| other things. The only thing left was the cable modem.
|
| To really make matters confusing for Comcast, the cable
| modem worked fine when connected directly to a PC.
| So I spent about an hour on the phone with some tech
| support guy named "Mike" in which he insisted over and
| over and over that if the cable modem works with a PC
| then it is fully functional and is not the problem. WRONG!!!
|
| Since cable modems are cheap now, I decided to run
| down to Office Max and get a cheap replacement to
| try out. I found a Best Data CMX300 for $60 and
| picked that up.
|
| Got home, hooked up the new cable modem, and
| presto, everything works fine.
|
| So for the record, it is quite possible for a cable modem
| to work fine with a PC but NOT WORK WITH A ROUTER.
| I have no idea technically why this can happen, but clearly
| it can.
|
| I could hope the paid chimps that work for Comcast would
| read this forum, but I assume they don't.
|
| Alan
|
| P.S. We did get competent and friendly help from the Comcast
| people who helped us out with the new modem setup. It was
| just the moron named "Mike" that is giving Comcast a bad rep.
|
|

"David H. Lipman" <DLipman~nospam~@Verizon.Net> wrote in message
news:u6xQc.12013$qM.3435@trndny01...
On comcast, that's not necessary. Otherwise, I wouldn't be able to post
this. To the OP, be sure that you get a receipt when you turn in the
defective modem. I turned in a defective Motorola SB5100 to Comcast several
months ago. I'm still fighting with Comcast's billing department over
rental fees for a modem that I do not have. This in spite of the fact that
I have a receipt for turning in the modem, and have gladly provided same to
Comcast. -Dave

"Dave C." <mdupre@sff.net> wrote in message
news:2nflifFev1qU1@uni-berlin.de...
Yeah, I actually remember previous posts to this effect. I may not even turn
the old modem in, since under my plan I'm not paying rent for it, so there
is
not much reason to do so. I'll just keep it until one day when I have the
privilege of switching to a competent service. Whoever activated the new
modem did take note of the identity of the broken modem, however. Not
sure if that means they will expect it to be turned in.

Alan

"Alan Wright" <alan@yahoo.com> wrote in message
news:2audnRZ1rb_gF4_cRVn-gA@giganews.com...
no.
if your service does work with the cable modem connected directly to your
computer then the problem is not with comcast.

"Giles Harney" <gharney@comcast.net> wrote in message
news:Abidnewrx4aoNY_cRVn-ug@comcast.com...
Wrong! And I proved it. Communication happened to work between
the cable modem and a computer, but not between the cable modem
and different routers. There are a variety of technical reasons why this
can occur, and the particular routers involved may be more or less
prone to this. Nonetheless, they previously and still work with other
cable modems, just not the one that went bad. It could be that other
routers might have still worked with this cable modem, but had Comcast
simply agreed to exchange modems with me, the problem would also
have been fixed just as easily. The fact that they would not swap the
modem (which would have cost them next to nothing) is just plain
horrible customer service.

Incidentally, the problem with the modem in question was acquired
at 4PM yesterday during a lightning storm. I note that a couple of my
neighbors have had Comcast out today as well. Coincidence?

Alan

That's correct, but it doesn't mean that the modem isn't broken. IF the
modem really won't work with any router, then there are three possibilities,
two of which have already been ruled out. The third possibility is broken
modem. Having trouble visualizing this?

A couple months ago, there was a NIC that would not work with computer A,
but would work with computer B. In simple terms, logically, you'd say the
NIC is OK and computer A is broken, right? Now consider that any other NIC
of the exact same make and model would work with BOTH computers. That
really happened, it was a bug (one of many) that my employer sent me to
Pennsylvania to troubleshoot. It turned out that the NIC was indeed bad,
even though it would work with computer B.

So it's possible for a networking component (cable modem, in this case) to
"work" and still be bad. IMHO, if a cable modem won't work with a router,
then it is indeed broken, even if it will work connected directly to a PC.
(that is, assuming all components are set up correctly) If more than one
router won't work on a system where no mac spoofing is required, then that
kind of points to a bad cable modem. -Dave

Alan Wright wrote:

That's assuming they can read. ;-)

--

(This space intentionally left blank)

"Dave C." <mdupre@sff.net> wrote in message
news:2nfu4vFid9vU1@uni-berlin.de...

thank you

James Knott wrote:

My experience with Comcast reps is that

1. They're morons
2. They're rude
3. They represent the best of Comcast.


N.B. At my home Comcast will soon be replaced by DSL

Never anonymous Bud wrote:

Verizon personnel are NOT rude. However their technical support personnel are incompetent.
Not so with Customer Service or Billing.

Dave




"Never anonymous Bud" <newskat@katxyzkave.net> wrote in message
news:brt7h0pm17p1hfa8il2f5s7dn0t56hbnjt@4ax.com...
| Having escaped, in tact, from the Democratic Convention, "e.jensen"
<e.jensen@comcast.net> inked:
|
| >My experience with Comcast reps is that
| >
| >1. They're morons
| >2. They're rude
| >3. They represent the best of Comcast.
| >
| >
| >N.B. At my home Comcast will soon be replaced by DSL
|
|
| And you think Comcast is incompetent and rude!
|
|
|
|
|
| --
|
| The truth is out there,
|
| but it's not interesting enough for most people.

"Giles Harney" <gharney@comcast.net> wrote in message
news:Abidnewrx4aoNY_cRVn-ug@comcast.com...
I have to agree with this; when you were change routers etc., were you also
changing ethernet cables being used to connect to the modem? Could it have
been as simple as a cable issue?

"Alan Wright" <alan@yahoo.com> wrote in message
news:A-ydncCNs4SbKI_cRVn-ug@giganews.com...

Since I am the proud owner of a SB4100 I think I can shed some light on this
situation. The SB4100 is a 10Mbps device. Not 100Mbps. There is a *known
problem* with the SB4100 which causes it to not automatically negotiate a
10Mbps connection to some 10/100 devices. Routers are especially a problem
here. They simply may not connect to the SB4100 when plugged in. However a
PC NIC being a different type of device with a different chipset and
firmware may be compatible with the SB4100.

Knowing that this a problem, I had my first brand-N router set up manually
for a 10Mbps connection. My new brand-N router does not offer the ability to
manually select 10Mbps but at least it handles the WAN connection correctly.
I am an advocate of buying your own cable modem because 1) it comes with a
manual and 2) you have a choice on which model you get.

Sadly, I have had plenty of experience with devices that refuse to connect
to each other but will readily connect to a third.

As others have said, you have proved nothing except your need to blame
someone else. I would suggest that you use your now-functional Internet
connection to RTFM and STFW.

--
Basic Bob
gbasigcbobg@gatt.gnet
the g's are silent

If the
"Basic Bob" <gbasigcbobg@gatt.gnet> wrote in message
news:JsidnWRJ5NoOsIncRVn-sQ@comcast.com...
|
| "Alan Wright" <alan@yahoo.com> wrote in message
| news:A-ydncCNs4SbKI_cRVn-ug@giganews.com...
| >
| > "Giles Harney" <gharney@comcast.net> wrote in message
| > news:Abidnewrx4aoNY_cRVn-ug@comcast.com...
| > >
| > > "Alan Wright" <alan@yahoo.com> wrote in message
| > > news:2audnRZ1rb_gF4_cRVn-gA@giganews.com...
| > > > To really make matters confusing for Comcast, the cable
| > > > modem worked fine when connected directly to a PC.
| > > > So I spent about an hour on the phone with some tech
| > > > support guy named "Mike" in which he insisted over and
| > > > over and over that if the cable modem works with a PC
| > > > then it is fully functional and is not the problem. WRONG!!!
| > >
| > > no.
| > > if your service does work with the cable modem connected directly to
| your
| > > computer then the problem is not with comcast.
| >
| > Wrong! And I proved it. Communication happened to work between
| > the cable modem and a computer, but not between the cable modem
| > and different routers. There are a variety of technical reasons why this
| > can occur, and the particular routers involved may be more or less
| > prone to this. Nonetheless, they previously and still work with other
| > cable modems, just not the one that went bad. It could be that other
| > routers might have still worked with this cable modem, but had Comcast
| > simply agreed to exchange modems with me, the problem would also
| > have been fixed just as easily. The fact that they would not swap the
| > modem (which would have cost them next to nothing) is just plain
| > horrible customer service.
| >
| > Incidentally, the problem with the modem in question was acquired
| > at 4PM yesterday during a lightning storm. I note that a couple of my
| > neighbors have had Comcast out today as well. Coincidence?
| >
| > Alan
| >
| >
|
|
| Since I am the proud owner of a SB4100 I think I can shed some light on this
| situation. The SB4100 is a 10Mbps device. Not 100Mbps. There is a *known
| problem* with the SB4100 which causes it to not automatically negotiate a
| 10Mbps connection to some 10/100 devices. Routers are especially a problem
| here. They simply may not connect to the SB4100 when plugged in. However a
| PC NIC being a different type of device with a different chipset and
| firmware may be compatible with the SB4100.
|
| Knowing that this a problem, I had my first brand-N router set up manually
| for a 10Mbps connection. My new brand-N router does not offer the ability to
| manually select 10Mbps but at least it handles the WAN connection correctly.
| I am an advocate of buying your own cable modem because 1) it comes with a
| manual and 2) you have a choice on which model you get.
|
| Sadly, I have had plenty of experience with devices that refuse to connect
| to each other but will readily connect to a third.
|
| As others have said, you have proved nothing except your need to blame
| someone else. I would suggest that you use your now-functional Internet
| connection to RTFM and STFW.
|
| --
| Basic Bob
| gbasigcbobg@gatt.gnet
| the g's are silent
|
|
|
|

Bob, where are you getting your information ? It is so wrong !

I have extracted the following information from Motorola's SB4100 (basically same for
SB4100E and SB4200) datasheet in PDF format
http://broadband.motorola.com/noflas...atasheets.html

"GENERAL
Cable Interface . . . . . . . . . . . . . . . . . . . . . F-Connector, female, 75 ?
CPE Network Interface. . . . . . . . . . . . . . . . USB, Ethernet 10/100BaseT
.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (auto sensing)
Data Protocol . . . . . . . . . . . . . . . . . . . . . . TCP/IP
Dimensions . . . . . . . . . . . . . . . . . . . . . . . 7.2" H x 2.0" W x 7.8" L
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Watts (nominal)
Input Power . . . . . . . . . . . . . . . . . . . . . . . 100-240 VAC, 50-60 Hz"

So based upon the manufacturer's documentation, any device that connects to to the SB4100
should be able to perform N-Way negotiation.

BTW: the chip-set has nothing to do with this. The chip-set has to conform to Ethernet
standards and if can't communicate with another Ethernet device than it does not conform to
Ethernet standards or is broken.

Talk about RTFB !

Dave



"Basic Bob" <gbasigcbobg@gatt.gnet> wrote in message
news:JsidnWRJ5NoOsIncRVn-sQ@comcast.com...

| Since I am the proud owner of a SB4100 I think I can shed some light on this
| situation. The SB4100 is a 10Mbps device. Not 100Mbps. There is a *known
| problem* with the SB4100 which causes it to not automatically negotiate a
| 10Mbps connection to some 10/100 devices. Routers are especially a problem
| here. They simply may not connect to the SB4100 when plugged in. However a
| PC NIC being a different type of device with a different chipset and
| firmware may be compatible with the SB4100.
|
| Knowing that this a problem, I had my first brand-N router set up manually
| for a 10Mbps connection. My new brand-N router does not offer the ability to
| manually select 10Mbps but at least it handles the WAN connection correctly.
| I am an advocate of buying your own cable modem because 1) it comes with a
| manual and 2) you have a choice on which model you get.
|
| Sadly, I have had plenty of experience with devices that refuse to connect
| to each other but will readily connect to a third.
|
| As others have said, you have proved nothing except your need to blame
| someone else. I would suggest that you use your now-functional Internet
| connection to RTFM and STFW.
|
| --
| Basic Bob
| gbasigcbobg@gatt.gnet
| the g's are silent
|
|
|
|

Sorry -- Cat got on the keyboard !

Dave ;-)

That wouldn't happen with Comcast here in Macomb, Michigan. If you change
your cable modem, your not even going to be able to connect. You have to
call them, and give them the MAC address of your new cable modem, and they
have to provision it, before it will connect to their servers.

Bill Crocker


"Alan Wright" <alan@yahoo.com> wrote in message
news:2audnRZ1rb_gF4_cRVn-gA@giganews.com...

"David H. Lipman" <DLipman~nospam~@Verizon.Net> wrote in message
news:vPWQc.641$Po1.126@trndny08...
I agree that any device *should* be able to connect. I got my SB4100 when it
was the current model 2.5 years ago, and at that time there were
connectivity issues which could be resolved by forcing the router to 10M. I
can no longer duplicate this problem because I upgraded my router, which now
correctly negotiates the connection. So one might deduce that the problem is
with the old router. Anyway, I apologize for the RTFM and STFW because the
information is now lost.

Unfortunately, knowledge and support for discontinued equipment is difficult
to come by. This is one reason I would not rent an obviously used and
obolete modem from Comcast. As long as I have to support my own network, I
might as well spend a few bucks to get good, easy-to-support equipment.

Sadly some of the industrial Web-enabled devices that I have encountered
also have connectivity problems, and the only choice is to come up with
work-arounds, since the manufacturer will never agree to alter their product
just because it will not connect to one customer's other-brand equipment.

--
Basic Bob
gbasigcbobg@gatt.gnet
the g's are silent

"Basic Bob" <gbasigcbobg@gatt.gnet> wrote in message
news:JsidnWRJ5NoOsIncRVn-sQ@comcast.com...
Bob, you don't know what you are talking about. The SB4100 I was using
worked fine for a couple of years with several different routers. It only
stopped
working after a lighting storm. You may be slightly correct in thinking that
the
NICs in my PCs are better at handling poor signal levels while the routers
could not. However, I *am* blaming the correct source of the problem, as
the cable modem was the only thing that changed such that it no longer
performed as well as before.

Alan