Re: Block traffic not orignating from ISP autonomous system

traffic is coming back from ISP-A , but orignating from another ISP......
traffic needs to be filtered on ISP-A, if not orignating in ISP-A....

how URPF can help in this case.

On Wed, Jun 2, 2010 at 7:25 PM, Tyson Scott <tscott_at_ipexpert.com> wrote:

> Put unicast reverse path filtering on your inside interfaces to stop user A
> from originating traffic internally from an external address.
>
> Regards,
>
> Tyson Scott - CCIE #13513 R&S, Security, and SP
> Managing Partner / Sr. Instructor - IPexpert, Inc.
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> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
> jack
> daniels
> Sent: Wednesday, June 02, 2010 7:18 AM
> To: Cisco certification
> Subject: Block traffic not orignating from ISP autonomous system
>
> Hi Guys,
>
> I'm facing a issue and stuck on a thought process , would appreciate if
> some
>
> way you guys can show with your experience in industry -
>
>
>
> ISSUE ----
>
>
> user X spoofs IP ADDRESS OF ISP-A and sends traffic out to internet...
> now when traffic is comming back via ISP-A... I want to block such traffic
> which is not orignating from my ISP...
> but catch here is ---- filtering is to be done in ISP ...so putiing acl for
> each users and ports is not scallable.....
> Please help with any way out ...
>
> Thanks and Regards
>
>
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Received on Wed Jun 02 2010 - 22:21:43 ART