Re: OT: PPPoEoATM

Yes.

--
Marko Milivojevic - CCIE #18427
Senior Technical Instructor - IPexpert
FREE CCIE training: http://bit.ly/vLecture
Mailto: markom_at_ipexpert.com
Telephone: +1.810.326.1444
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On Thu, Jul 21, 2011 at 17:49, Joe Astorino <joeastorino1982_at_gmail.com> wrote:
> So when the ATM cells hit the DSLAM and it decapsulates everything, the
> DSLAM has ethernet already underneath to pass further upstream in the SP
> network?
>
> On Thu, Jul 21, 2011 at 8:03 PM, Marko Milivojevic <markom_at_ipexpert.com>
> wrote:
>>
>> Most of DSLAMs have Ethernet aggregation ant not ATM.
>>
>> --
>> Marko Milivojevic - CCIE #18427
>> Senior Technical Instructor - IPexpert
>>
>> FREE CCIE training: http://bit.ly/vLecture
>>
>> Mailto: markom_at_ipexpert.com
>> Telephone: +1.810.326.1444
>> Web: http://www.ipexpert.com/
>>
>> On Thu, Jul 21, 2011 at 14:59, Joe Astorino <joeastorino1982_at_gmail.com>
>> wrote:
>> > Does anybody have a clear explanation as to why many DSL service
>> > providers
>> > prefer to use PPPoEoATM instead of just PPPoATM when terminating DSL on
>> > a
>> > Cisco router? B For example, let's say I have a Cisco router with a DSL
>> > (ATM)
>> > interface for the WAN side of the connection and a standard FastEthernet
>> > interface facing the users.
>> >
>> > When the user sends an IP packet, it is encapsulated in an ethernet
>> > frame.
>> > When it hits the router, the ethernet frame is stripped off and the
>> > router
>> > encapsulates the IP packet into a PPP frame. B NOW...at that point one of
>> > two
>> > things happens -- It can encapsulate the PPP into ATM and send it along
>> > the
>> > way as PPPoATM or it can encapsulate the PPP into ethernet, and THEN
>> > encapsulate that entire thing into ATM for what amounts to PPPoEoATM.
>> > B What
>> > is the point of the extra ethernet header?
>> >
>> > Is this just a compatibility thing because they figure many end users
>> > won't
>> > have "ATM" interfaces and will be interfacing directly from their PC
>> > where
>> > PPPoE might already be there? B It's always bugged me.
>> >
>> > Thanks for any input!
>> >
>> > --
>> > Regards,
>> >
>> > Joe Astorino
>> > CCIE #24347
>> > Blog: http://astorinonetworks.com
>> >
>> > "He not busy being born is busy dying" - Dylan
>> >
>> >
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>> >
>
>
>
> --
> Regards,
>
> Joe Astorino
> CCIE #24347
> Blog: http://astorinonetworks.com
>
> "He not busy being born is busy dying" - Dylan
Blogs and organic groups at http://www.ccie.net