Re: L2TPV3

Super explanation Brian ! Thanks ! things are becoming clear now !
back to reading again

Gaurav Madan

On Mon, Feb 21, 2011 at 8:26 PM, Brian McGahan <bmcgahan_at_ine.com> wrote:
> L2TPv3 is a layer 2 VPN over IP. Let's say that the service provider has an IP cloud for transit, but wants to sell layer 2 services like Frame Relay to a customer. From the customer's perspective, this is just normal Frame Relay service. The customer routers are assign Frame Relay DLCIs, and their endpoints are on the same IP subnet. In the SP network, the Frame Relay packets are tunneled over IP using L2TPv3. This means that the SP network doesn't have to maintain a true end-to-end Frame Relay network, but can still sell this service. Likewise they could sell Metro Ethernet, ATM, or HDLC/PPP services, while tunneling these all over IP in the transit network.
>
> The other version of this for MPLS networks is called Any Transport over MPLS (AToM). AToM is the same as L2TPv3, but the encapsulation is over an MPLS header instead of an L2TPv3 header. Likewise from the SP network's perspective they can sell whatever layer 2 VPN service they want (Ethernet, Frame Relay, ATM, etc.), and support it all with a single MPLS transit network.
>
> HTH,
>
> Brian McGahan, CCIE #8593 (R&S/SP/Security)
> bmcgahan_at_INE.com
>
> Internetwork Expert, Inc.
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>
> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of GAURAV MADAN
> Sent: Monday, February 21, 2011 8:37 AM
> To: Cisco certification
> Subject: L2TPV3
>
> Hi
>
> Sorry for very basic question .. This is a new technology for me ..
>
> I am reading L2TPV3 chapter from "MPLS on CIsco IOS" book ..
>
> The configs ( static and dynamic L2TPV3 ) looks OK ...
>
> But the very basic idea of L2TPV3 is not at all clear to me . What
> special are we doing here ?
> Can you tell me the use of where is it used to tunnel the pkts over
> IP cloud (Non-MPLS cloud) .
>
> I am looking for a real world case where L2TPV3 is used and how ?
> How providers and clients (if at all) are making best out of this ?
>
> Please shed some light on this
>
> Gaurav Madan
>
>
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Received on Mon Feb 21 2011 - 20:58:01 ART