Hi - > From: "Hector" <sant9442@xxxxxxxxx> > Cc: <ietf@xxxxxxxx> > Sent: Saturday, September 03, 2011 7:52 AM > Subject: Re: 2119bis ... > For protocol v2.0, X2 is a improved version of X1. > > SHOULD USE X2 IF POSSIBLE, IF NOT > MUST USE X1 > > Its the same as saying > > MUST USE X2 first or X1 as a fallback ... No, those two formulations mean different things. If the first "SHOULD" were a "MUST", then they'd be close but still not equivalent. Randy _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf