Hi Shahram,

It may be ok as long as the HWs are incrementally recalculating it. However, if 
its being done afresh then we have an issue. I don't see how the HW behavior 
can be mandated in a spec. 

Cheers, Manav

> -----Original Message-----
> From: Shahram Davari [mailto:[email protected]] 
> Sent: Friday, January 21, 2011 4.59 AM
> To: Bhatia, Manav (Manav); [email protected]
> Subject: RE: UDP checksum
> 
> Hi Manav,
> 
> UDP checksum is usually not verified before updating the CF. 
> After CF update it is incrementally recalculated. The end 
> host will then verify the checksum for correctness.
> 
> Regards,
> Shahram
> 
> -----Original Message-----
> From: [email protected] 
> [mailto:[email protected]] On Behalf Of Bhatia, Manav (Manav)
> Sent: Thursday, January 20, 2011 3:16 PM
> To: [email protected]
> Subject: [TICTOC] UDP checksum
> 
> Hi,
> 
> Are the LSRs acting as TCs expected to verify the checksum 
> before they update the correction field? If no, then there is 
> no point in these LSRs in updating the UDP checksum as they 
> will "correct" the checksum when its recomputed after 
> modifying the CF field. In this case wouldn't it make more 
> sense to just update the checksum at the MPLS terminating point?
> 
> I also think that updating the UDP checksum may be redundant 
> as the LSRs are anyways verifying the outer ethernet checksum 
> before accepting any packets. Any thoughts here?
> 
> Cheers, Manav
> 
> --
> Manav Bhatia,
> IP Division, Alcatel-Lucent,
> Bangalore - India
> 
>  
> _______________________________________________
> TICTOC mailing list
> [email protected]
> https://www.ietf.org/mailman/listinfo/tictoc
> 
> 
> 
_______________________________________________
TICTOC mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/tictoc

Reply via email to