DOCSIS 3.0 & PPPoE/L2TP compatibility

iptech iptech at
Tue Jul 31 22:13:41 UTC 2012

Hey Ricky,

Yes that is the exact setup, the cableco bring the customer to us via 
L2TP, and now want to do PPTP only.

I will keep digging on the ARRIS, which I have been told is a C4 system. 
Although their website doesnt show much tech specs.

They are pushing for the L3 option since their CMTS will now be a hop in 
the path between the customer and us, instead of L2 transparent.



On 7/31/2012 5:19 PM, Ricky Beam wrote:
> On Mon, 30 Jul 2012 08:33:51 -0400, iptech <iptech at> wrote:
>> 3.0 compliant setup, and this standard no longer supports PPPoE via 
>> L2TP, and can now only offer PPTP for terminating with us.
> As I recall from my reading of "the standard", there's nothing in 
> there to prevent any tunneling on top of the DOCSIS bridged ethernet.
> I suspect this is not a "standard" problem but an ISP problem... their 
> new hardware doesn't support PPPoE/L2TP, it's an additional license, 
> or they don't know how (or unwilling) to configure it.
> (I'm assuming the PPPoE is between you and the customer, and L2TP is 
> between your network and the cable network. i.e. L2TP is how your 
> customers are brought to you from the cable network.)
> I have no documentation on ARRIS either, so I don't know what they 
> can/cannot do.

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