multiple DSL lines for single infrastructure

16 Mar 2005 9:19 PM

Phil Schuman

A friend with a small biz called and asked me a question
about how he can increase bandwidth by adding a 2nd DSL line.

He has a single DSL line, with a wireless router for laptops,
and a 24-port switch for the office hardwired desktops.
He wants to increase bandwidth by adding a 2nd DSL line,
along with a 2nd wireless router.

Now - the question - how to setup the infrastructure -

Each wireless router will have a different SSID - so that is ok -
BUT - how to handle the IP addressing between the 2 DSL routers...
THINKING - split the single wireless router subnet,
into two wireless router subnets - 192.168.10.x   and 192.168.20.x

HOWEVER -
Can they both co-exist on the same Ethernet physical network
and go thru the same Ethernet switch ?

Each PC/laptop GW will point to each subnet's router,
so that should be ok -

But - since they are on the same "physical network"
if I wanted to talk from a PC or laptop on .10 to a printer on .20
will ARP's from the .20 have been recorded by the .10 PC,
or am I always forced to go to the GW router for resolution.
And, if I go to the router, will they have "seen" each others address,
or will I need to manually add a static address for each other's subnet
?

tnx for the discussion, comments, education -

DSL line #1                                DSL line #2
DSL modem #1                         DSL modem #2
Wireless router (.10.1)              Wireless router (.20.1)

             |
|
             |----------->>> single switch <<<<---------|
             |
|

192.168.10.100                             192.168.20.100
192.168.10.101                             192.168.20.101
GW = 192.168.10.1                        GW = 192.168.20.1

16 Mar 2005 9:46 PM

J. Clarke

Phil Schuman wrote:

> A friend with a small biz called and asked me a question
> about how he can increase bandwidth by adding a 2nd DSL line.
>
> He has a single DSL line, with a wireless router for laptops,
> and a 24-port switch for the office hardwired desktops.
> He wants to increase bandwidth by adding a 2nd DSL line,
> along with a 2nd wireless router.

Froogle "load balancing router". It sounds like you're drastically
overcomplicating something that should be fairly simple to do.

Show quoteHide quote

> Now - the question - how to setup the infrastructure -
>
> Each wireless router will have a different SSID - so that is ok -
> BUT - how to handle the IP addressing between the 2 DSL routers...
> THINKING - split the single wireless router subnet,
> into two wireless router subnets - 192.168.10.x   and 192.168.20.x
>
> HOWEVER -
> Can they both co-exist on the same Ethernet physical network
> and go thru the same Ethernet switch ?
>
> Each PC/laptop GW will point to each subnet's router,
> so that should be ok -
>
> But - since they are on the same "physical network"
> if I wanted to talk from a PC or laptop on .10 to a printer on .20
> will ARP's from the .20 have been recorded by the .10 PC,
> or am I always forced to go to the GW router for resolution.
> And, if I go to the router, will they have "seen" each others address,
> or will I need to manually add a static address for each other's subnet
> ?
>
> tnx for the discussion, comments, education -
>
>
> DSL line #1                                DSL line #2
> DSL modem #1                         DSL modem #2
> Wireless router (.10.1)              Wireless router (.20.1)
>              |
> |
>              |----------->>> single switch <<<<---------|
>              |
> |
> 192.168.10.100                             192.168.20.100
> 192.168.10.101                             192.168.20.101
> GW = 192.168.10.1                        GW = 192.168.20.1

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

16 Mar 2005 10:07 PM

David H. Lipman

Show quote Hide quote

From: "Phil Schuman" <pschuman_NO_SPAM_ME@interserv.com>

| A friend with a small biz called and asked me a question
| about how he can increase bandwidth by adding a 2nd DSL line.
|
| He has a single DSL line, with a wireless router for laptops,
| and a 24-port switch for the office hardwired desktops.
| He wants to increase bandwidth by adding a 2nd DSL line,
| along with a 2nd wireless router.
|
| Now - the question - how to setup the infrastructure -
|
| Each wireless router will have a different SSID - so that is ok -
| BUT - how to handle the IP addressing between the 2 DSL routers...
| THINKING - split the single wireless router subnet,
| into two wireless router subnets - 192.168.10.x   and 192.168.20.x
|
| HOWEVER -
| Can they both co-exist on the same Ethernet physical network
| and go thru the same Ethernet switch ?
|
| Each PC/laptop GW will point to each subnet's router,
| so that should be ok -
|
| But - since they are on the same "physical network"
| if I wanted to talk from a PC or laptop on .10 to a printer on .20
| will ARP's from the .20 have been recorded by the .10 PC,
| or am I always forced to go to the GW router for resolution.
| And, if I go to the router, will they have "seen" each others address,
| or will I need to manually add a static address for each other's subnet
| ?
|
| tnx for the discussion, comments, education -
|
| DSL line #1                                DSL line #2
| DSL modem #1                         DSL modem #2
| Wireless router (.10.1)              Wireless router (.20.1)
|>
|> ----------->>> single switch <<<<---------|
|>
| 192.168.10.100                             192.168.20.100
| 192.168.10.101                             192.168.20.101
| GW = 192.168.10.1                        GW = 192.168.20.1
|

Your friend needs to double the DSL bandwidth and not get two DSL lines and really should be
SDSL rather than ADSL which he probably has. He will not double his bandwidth effectively
with two xDSL lines and two wireless Routers.

If the person really wants to xDSL lines tthen what is really needed is a Load Balanced
Router that has two WAN ports such as the Edimax PermaLink PRI-682
http://www.edimax.com/html/english/products/PRI682.htm

--
Dave

18 Mar 2005 1:29 PM

Phil Schuman

tnx for the comments about a dual port WAN router...
We'll have to look into those, but then how is the price,
and does each WAN port directly support DSL/PPPoE, etc ?
Here was another network design that I thought off....

Instead of having 2 subnets, and then having to setup a route between
them,
why not just keep ONE subnet, as the problem is just with the GW address
to force 1/2 the traffic to each DSL line.... yeah, not load balanced,
but cheap :)
I wonder if this will work.... 192.168.1.xxx 255.255.255.0
Take each router, and setup it's DHCP with a limited number of addresses
(1/2 of the total), and with a unique range .100-.110 and .200-.210, but
on the same subnet. Then, both will reply to any subnet DHCP request,
and maybe 1/2 will be satisfied by each router. If not, then at least a
stop-gap measure will be that each router will only serve up 1/2 of the
PC's used. So, if say 20 PC's all try to get DHCP served, then 10 should
be "forced" to each router by the limited DHCP reply and it's associated
DHCP info (address, DNS, GW address).
thoughts ?

18 Mar 2005 4:23 PM

J. Clarke

Phil Schuman wrote:

> tnx for the comments about a dual port WAN router...
> We'll have to look into those, but then how is the price,

$150 and up.

> and does each WAN port directly support DSL/PPPoE, etc ?

Yes. They're designed specifically for that purpose.

Show quoteHide quote

> Here was another network design that I thought off....
>
> Instead of having 2 subnets, and then having to setup a route between
> them,
> why not just keep ONE subnet, as the problem is just with the GW address
> to force 1/2 the traffic to each DSL line.... yeah, not load balanced,
> but cheap :)
> I wonder if this will work.... 192.168.1.xxx 255.255.255.0
> Take each router, and setup it's DHCP with a limited number of addresses
> (1/2 of the total), and with a unique range .100-.110 and .200-.210, but
> on the same subnet. Then, both will reply to any subnet DHCP request,
> and maybe 1/2 will be satisfied by each router. If not, then at least a
> stop-gap measure will be that each router will only serve up 1/2 of the
> PC's used. So, if say 20 PC's all try to get DHCP served, then 10 should
> be "forced" to each router by the limited DHCP reply and it's associated
> DHCP info (address, DNS, GW address).
> thoughts ?

That's not going to force traffic to either line, it's just going to give
you messy DHCP. to make it work, you will probably need to lock IP
addresses to MAC addresses, which pretty much defeats the purpose of DHCP.

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

19 Mar 2005 11:55 PM

Phil Schuman

"J. Clarke" <jclarke.use***@snet.net.invalid> wrote in message
> That's not going to force traffic to either line, it's just going to
give
> you messy DHCP. to make it work, you will probably need to lock IP
> addresses to MAC addresses, which pretty much defeats the purpose of
DHCP.
>

If 10 PCs receive the GW address as 192.168.1.1
and 10 PCs receive the GW address as 192.168.1.2
then each "logical group" will use "their" GW and DSL line.
Yeah - it's not load balanced, but merely spliting
the infrastructure between 2 lines - a roll of the DHCP dice -
I know multiple GWs work, as we did it with our T1s and ISDN,
and also used multiple DHCP servers - with non-overlapping scopes.