[j-nsp] Ethernet Preamble and FCS on EoMPLS

Jonathan Looney jonlooney at gmail.com
Mon Sep 28 09:52:47 EDT 2009

On Fri, Sep 25, 2009 at 4:50 PM, Phil Bedard <philxor at gmail.com> wrote:

> The FCS is part of the frame... RFC4720 specifies a FCS retention indicator
> TLV, but I don't think it's ever been adopted by a vendor.
> Some saw the lack of transparency in delivering the FCS untouched as a
> security issue.  A valid original FCS on the remote end means the payload
> arrived unaltered through the transport network.
If they are concerned about data being altered during transit for security
reasons, they should be using IPSec.  Ethernet FCS isn't really a security
measure as much as an error-detection measure.


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