[ippm] Alissa Cooper's Discuss on draft-ietf-ippm-checksum-trailer-05: (with DISCUSS)

["Alissa Cooper" <[e-mail]>]

Alissa Cooper has entered the following ballot position for
draft-ietf-ippm-checksum-trailer-05: Discuss

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DISCUSS:
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There seems to be a bit of a disconnect between this text in 3.2:

"As specified in Section 3.4. , the Checksum Complement should only be
used in unauthenticated mode."

and this text in 3.4.1:

"A Checksum Complement MAY be used when authentication is enabled. In
   this case an intermediate entity can timestamp test packets and
   update their Checksum Complement field without modifying the HMAC."

I can see why not to use the checksum complement in encrypted mode, but
don't see why it can't be used in authenticated mode for TWAMP.