Kerry Lynn <[email protected]> writes: > On Fri, Sep 3, 2021 at 5:29 PM Erik Kline <[email protected]> wrote: >> I've been trying to catch up on and close all outside INT area errata. In >> so doing, I've come across: >> >> https://www.rfc-editor.org/errata/eid4814 >> >> filed against RFC 6282. >> >> My inclination is to reject this erratum, since 255 is in fact "used to >> verify that a communication occurs over a single-hop", and this sentence >> provides some background for the document treating 255 later on (section >> 3.1.1). >> > I agree that the errata as submitted appears to be incorrect. However, > that doesn't necessarily > mean the statement in the RFC is clear. Let's start with the proposed > wording "... a Hop Limit > value of 1 is often used to verify that a communication occurs over a > single hop." I believe a > sender would set a value of 1 to _ensure_ a packet only travels over a > single hop. A receiver > might use the comparison value of 255 to _verify_ a received packet has not > been routed. > However, the preceding sentence in RFC 6282 suggests that 64 is also a > common value for > outbound traffic. In the event, a value of 64 _might_ indicate the packet > has not been routed, > but it might also indicate the packet traveled 255 - 64 = 191 hops before > reaching the receiver, > so 255 seems the only reliable comparison value. (Why would a receiver need > to know this?)
I remember filing this erratum, and at the time, someone pointed out how the 255 hop-limit is used, etc. as Kerry describes. I'm surprised that the erratum hasn't been closed previously. The flagged statement in the RFC isn't clear if one isn't steeped in 6lowpan networking, though it isn't necessary to understand and apply the RFC. Dale _______________________________________________ 6lo mailing list [email protected] https://www.ietf.org/mailman/listinfo/6lo
