Re: serial-line protocols

[Raj Malhotra <ral.mal () gmail com>]

hi

May be i was not clear in conveying our need. 

We first need to tap the PPP link to get the frames and then access
the IP datagram. In case of an ethernet tap, the 7-byte ethernet
preamble is an indication of the beginning of a frame and hence the
tap is in sync with the link.

In case of PPP-links how is this acheived.

Thanks
Raj
 

On Mon, 30 Aug 2004 00:43:07 +0800, Fook Ming EE <eeefm () singnet com sg> wrote:
> Hi, I think you got to do it at IP level instead of link-level of PPP.
>
> Cheers,
> FM
>
>
>
> -----Original Message-----
> From: Raj Malhotra [mailto:ral.mal () gmail com]
> Sent: Thursday, August 26, 2004 8:08 PM
> To: focus-ids () securityfocus com
> Subject: serial-line protocols
>
> Hi,
>
> We have two routers connected by fibre running a serial-line protocol
> like PPP. If we need to deploy a NIDS running on a linux-box having a
> 10/100/1000 ethernet card, would an optical-tap with a protocol
> converter suffice?
>
> With a serial-line protocol would any synchronization at the protocol
> converter be necessary?