ADSL to Cable

I have a wireless ADSL router (a 3COM 3CRWDR100A-72) but I'm looking to get
cable soon (NTL).

Would it be possible to still use this router for my wireless internet
connection?

Could I plug the ethernet cable from the cable modem into the router and
connect to the internet that way?

Thanks in advance.

"Andy" <(E-Mail Removed)> wrote in message
news:459ff24a$0$8758$(E-Mail Removed)...
>I have a wireless ADSL router (a 3COM 3CRWDR100A-72) but I'm looking to get
>cable soon (NTL).
>
> Would it be possible to still use this router for my wireless internet
> connection?
>
> Could I plug the ethernet cable from the cable modem into the router and
> connect to the internet that way?
>
> Thanks in advance.
>
>
>
Link to the router specs:
http://www.3com.com/products/en_US/d...htype=purchase

Andy wrote in message
459ff24a$0$8758$(E-Mail Removed):

> I have a wireless ADSL router (a 3COM 3CRWDR100A-72) but I'm looking
> to get cable soon (NTL).
>
> Would it be possible to still use this router for my wireless internet
> connection?
>
> Could I plug the ethernet cable from the cable modem into the router
> and connect to the internet that way?
>
> Thanks in advance.

My understanding is that this is not possible. Unless anyone knows
differently.

A "router" consists of several components in the same box:

- for an ADSL router: ADSL modem -> router -> 4-port switch / wireless
access point

- for a cable router: router -> 4-port switch / wireless access point (the
modem is external to the "router" box)

For both an ADSL and a cable router, the input is a public IP address and
the outputs are private IP addresses of the form 192.168.x.y. In between the
two is the NAT (network
address translation) of the router itself.

You *could* plug the output of the cable modem into one of the network ports
of the router box but all you would be doing is plugging it into the switch,
so all other the devices would see public IP addresses - no address
translation would take place.

Martin Underwood wrote:
> Andy wrote in message
> 459ff24a$0$8758$(E-Mail Removed):
>
>> I have a wireless ADSL router (a 3COM 3CRWDR100A-72) but I'm
>> looking
>> to get cable soon (NTL).
>>
>> Would it be possible to still use this router for my wireless
>> internet connection?
>>
>> Could I plug the ethernet cable from the cable modem into the
>> router
>> and connect to the internet that way?
>>
>> Thanks in advance.
>
> My understanding is that this is not possible. Unless anyone knows
> differently.
>
> A "router" consists of several components in the same box:
>
> - for an ADSL router: ADSL modem -> router -> 4-port switch /
> wireless
> access point
>
> - for a cable router: router -> 4-port switch / wireless access
> point
> (the modem is external to the "router" box)
>
> For both an ADSL and a cable router, the input is a public IP
> address
> and the outputs are private IP addresses of the form 192.168.x.y. In
> between the two is the NAT (network
> address translation) of the router itself.
>
> You *could* plug the output of the cable modem into one of the
> network ports of the router box but all you would be doing is
> plugging it into the switch, so all other the devices would see
> public IP addresses - no address translation would take place.

Actually if they're thinking of going to NTL, they only allocate 1 IP
so it would be pointless trying to use a switch, you would need a
router for more than one machine

kráftéé wrote in message
enp0lo$r91$(E-Mail Removed):

> Martin Underwood wrote:
>> Andy wrote in message
>> 459ff24a$0$8758$(E-Mail Removed):
>>
>>> I have a wireless ADSL router (a 3COM 3CRWDR100A-72) but I'm
>>> looking
>>> to get cable soon (NTL).
>>>
>>> Would it be possible to still use this router for my wireless
>>> internet connection?
>>>
>>> Could I plug the ethernet cable from the cable modem into the
>>> router
>>> and connect to the internet that way?
>>>
>>> Thanks in advance.
>>
>> My understanding is that this is not possible. Unless anyone knows
>> differently.
>>
>> A "router" consists of several components in the same box:
>>
>> - for an ADSL router: ADSL modem -> router -> 4-port switch /
>> wireless
>> access point
>>
>> - for a cable router: router -> 4-port switch / wireless access
>> point
>> (the modem is external to the "router" box)
>>
>> For both an ADSL and a cable router, the input is a public IP
>> address
>> and the outputs are private IP addresses of the form 192.168.x.y. In
>> between the two is the NAT (network
>> address translation) of the router itself.
>>
>> You *could* plug the output of the cable modem into one of the
>> network ports of the router box but all you would be doing is
>> plugging it into the switch, so all other the devices would see
>> public IP addresses - no address translation would take place.
>
> Actually if they're thinking of going to NTL, they only allocate 1 IP
> so it would be pointless trying to use a switch, you would need a
> router for more than one machine

Which is what I was alludding to (though I didn't say explicitly) is that
ISPs normally only allocate you one IP address, so a switch would be no use
because it wouldn't perform the job that a router does of translating
between the various private addresses of the individual PCs and the single
public IP that the ISP allocates you.

"Martin Underwood" <a@b> wrote in message
news:45a01324$0$8733$(E-Mail Removed)...
> kráftéé wrote in message
> enp0lo$r91$(E-Mail Removed):
>
>> Martin Underwood wrote:
>>> Andy wrote in message
>>> 459ff24a$0$8758$(E-Mail Removed):
>>>
>>>> I have a wireless ADSL router (a 3COM 3CRWDR100A-72) but I'm
>>>> looking
>>>> to get cable soon (NTL).
>>>>
>>>> Would it be possible to still use this router for my wireless
>>>> internet connection?
>>>>
>>>> Could I plug the ethernet cable from the cable modem into the
>>>> router
>>>> and connect to the internet that way?
>>>>
>>>> Thanks in advance.
>>>
>>> My understanding is that this is not possible. Unless anyone knows
>>> differently.
>>>
>>> A "router" consists of several components in the same box:
>>>
>>> - for an ADSL router: ADSL modem -> router -> 4-port switch /
>>> wireless
>>> access point
>>>
>>> - for a cable router: router -> 4-port switch / wireless access
>>> point
>>> (the modem is external to the "router" box)
>>>
>>> For both an ADSL and a cable router, the input is a public IP
>>> address
>>> and the outputs are private IP addresses of the form 192.168.x.y. In
>>> between the two is the NAT (network
>>> address translation) of the router itself.
>>>
>>> You *could* plug the output of the cable modem into one of the
>>> network ports of the router box but all you would be doing is
>>> plugging it into the switch, so all other the devices would see
>>> public IP addresses - no address translation would take place.
>>
>> Actually if they're thinking of going to NTL, they only allocate 1 IP
>> so it would be pointless trying to use a switch, you would need a
>> router for more than one machine
>
> Which is what I was alludding to (though I didn't say explicitly) is that
> ISPs normally only allocate you one IP address, so a switch would be no
> use because it wouldn't perform the job that a router does of translating
> between the various private addresses of the individual PCs and the single
> public IP that the ISP allocates you.
>
I only have 1 PC so would this work?

Andy wrote:
> "Martin Underwood" <a@b> wrote in message
> news:45a01324$0$8733$(E-Mail Removed)...
>> kráftéé wrote in message
>> enp0lo$r91$(E-Mail Removed):
>>
>>> Martin Underwood wrote:
>>>> Andy wrote in message
>>>> 459ff24a$0$8758$(E-Mail Removed):
>>>>
>>>>> I have a wireless ADSL router (a 3COM 3CRWDR100A-72) but I'm
>>>>> looking
>>>>> to get cable soon (NTL).
>>>>>
>>>>> Would it be possible to still use this router for my wireless
>>>>> internet connection?
>>>>>
>>>>> Could I plug the ethernet cable from the cable modem into the
>>>>> router
>>>>> and connect to the internet that way?
>>>>>
>>>>> Thanks in advance.
>>>>
>>>> My understanding is that this is not possible. Unless anyone
>>>> knows
>>>> differently.
>>>>
>>>> A "router" consists of several components in the same box:
>>>>
>>>> - for an ADSL router: ADSL modem -> router -> 4-port switch /
>>>> wireless
>>>> access point
>>>>
>>>> - for a cable router: router -> 4-port switch / wireless access
>>>> point
>>>> (the modem is external to the "router" box)
>>>>
>>>> For both an ADSL and a cable router, the input is a public IP
>>>> address
>>>> and the outputs are private IP addresses of the form 192.168.x.y.
>>>> In between the two is the NAT (network
>>>> address translation) of the router itself.
>>>>
>>>> You *could* plug the output of the cable modem into one of the
>>>> network ports of the router box but all you would be doing is
>>>> plugging it into the switch, so all other the devices would see
>>>> public IP addresses - no address translation would take place.
>>>
>>> Actually if they're thinking of going to NTL, they only allocate 1
>>> IP so it would be pointless trying to use a switch, you would need
>>> a
>>> router for more than one machine
>>
>> Which is what I was alludding to (though I didn't say explicitly)
>> is
>> that ISPs normally only allocate you one IP address, so a switch
>> would be no use because it wouldn't perform the job that a router
>> does of translating between the various private addresses of the
>> individual PCs and the single public IP that the ISP allocates you.
>>
> I only have 1 PC so would this work?

If you've only got one PC then why bother, just plug it straight into
the cable modem..

"kráftéé" <kraftee@b&e-cottee.me.uk> wrote in message
news:enpcho$cbb$(E-Mail Removed)...
> Andy wrote:
>> "Martin Underwood" <a@b> wrote in message
>> news:45a01324$0$8733$(E-Mail Removed)...
>>> kráftéé wrote in message
>>> enp0lo$r91$(E-Mail Removed):
>>>
>>>> Martin Underwood wrote:
>>>>> Andy wrote in message
>>>>> 459ff24a$0$8758$(E-Mail Removed):
>>>>>
>>>>>> I have a wireless ADSL router (a 3COM 3CRWDR100A-72) but I'm
>>>>>> looking
>>>>>> to get cable soon (NTL).
>>>>>>
>>>>>> Would it be possible to still use this router for my wireless
>>>>>> internet connection?
>>>>>>
>>>>>> Could I plug the ethernet cable from the cable modem into the
>>>>>> router
>>>>>> and connect to the internet that way?
>>>>>>
>>>>>> Thanks in advance.
>>>>>
>>>>> My understanding is that this is not possible. Unless anyone knows
>>>>> differently.
>>>>>
>>>>> A "router" consists of several components in the same box:
>>>>>
>>>>> - for an ADSL router: ADSL modem -> router -> 4-port switch /
>>>>> wireless
>>>>> access point
>>>>>
>>>>> - for a cable router: router -> 4-port switch / wireless access
>>>>> point
>>>>> (the modem is external to the "router" box)
>>>>>
>>>>> For both an ADSL and a cable router, the input is a public IP
>>>>> address
>>>>> and the outputs are private IP addresses of the form 192.168.x.y.
>>>>> In between the two is the NAT (network
>>>>> address translation) of the router itself.
>>>>>
>>>>> You *could* plug the output of the cable modem into one of the
>>>>> network ports of the router box but all you would be doing is
>>>>> plugging it into the switch, so all other the devices would see
>>>>> public IP addresses - no address translation would take place.
>>>>
>>>> Actually if they're thinking of going to NTL, they only allocate 1
>>>> IP so it would be pointless trying to use a switch, you would need a
>>>> router for more than one machine
>>>
>>> Which is what I was alludding to (though I didn't say explicitly) is
>>> that ISPs normally only allocate you one IP address, so a switch
>>> would be no use because it wouldn't perform the job that a router
>>> does of translating between the various private addresses of the
>>> individual PCs and the single public IP that the ISP allocates you.
>>>
>> I only have 1 PC so would this work?
>
> If you've only got one PC then why bother, just plug it straight into the
> cable modem..
>
The reason I posted this question is because of the NTL installation.

The PC is located at the back of the house and would require quite a long
cable run by the installer which may class as a non-standard installation.

I don't wish to have to pay any extra so I'm just investigating my options
at the moment.

Thanks for your comments.

....snip...

> The PC is located at the back of the house and would require quite a long
> cable run by the installer which may class as a non-standard installation.
>
> I don't wish to have to pay any extra so I'm just investigating my options
> at the moment.
>
> Thanks for your comments.

So do you have a wireless connection to your PC? If not, you really need is
a long ethernet cable from the front of house to the back. If you do have
wirelsss and depending on the max. speed your cable box will support,
wireless may be fine in which case you should be able to do the following...

1. Turn off all NAT on your router
2. Leave NAT on at your PC
3. Connect the router port (one of the "PC" ports not the ADSL bit!) to the
cable box
4. Connect wirelessly to the router from your PC.

Note that wireless is pretty poor through a house so you may find you get
poor speed but if it's faster than your cable connection then it won't
really matter.

Alternatively, a long ethernet cable will work fine. Routing it around the
house could be "fun" though.

Paul DS.

In article <45a09ff6$0$8758$(E-Mail Removed)>, Andy wrote:

> The reason I posted this question is because of the NTL installation.
>
> The PC is located at the back of the house and would require quite a long
> cable run by the installer which may class as a non-standard installation.
>
> I don't wish to have to pay any extra so I'm just investigating my options
> at the moment.

My NTL modem is at the back of the house. The installer was quite happy to run
a cable from the grey box at the front, all down one side and the back of the
house.