Hello Dhruv, I appreciate your help. :)
Thanks & Regards, Mrinmoy On Tue, Mar 24, 2020, 7:45 PM Dhruv Dhody <[email protected]> wrote: > Hi Mrinmoy, > > I will give authors some time to respond and confirm (and spin a new > update). I have noted this in the PCE WG wiki [ > https://trac.ietf.org/trac/pce/wiki/WikiStart ] to make sure we could > track this to closure. > > Thanks! > Dhruv > > On Tue, Mar 24, 2020 at 7:11 PM Mrinmoy Das <[email protected]> > wrote: > > > > Hi Dhruv, > > > > Thanks for your quick reply. > > > > I have added PCE WG in this mail. More inline. > > > > Thanks & Regards, > > Mrinmoy > > > > On Tue, Mar 24, 2020 at 6:00 PM Dhruv Dhody <[email protected]> > wrote: > >> > >> Hi Mrinmoy, > >> > >> I was suggest you to also include [email protected]; WG could benefit from > >> the discussion in future. More inline. > >> > >> On Tue, Mar 24, 2020 at 5:08 PM Mrinmoy Das <[email protected]> > wrote: > >> > > >> > Respected Authors and Contributors, > >> > > >> > Hope you all are doing well and safe in this tough times of Corona > Virus Outbreak. > >> > > >> > I like to draw your attention regarding some parts of > draft-ietf-pce-binding-label-sid-02 which I didn't able to understand > properly. > >> > > >> > 1. BT = 0: The binding value is an MPLS label carried in the format > >> > > >> > specified in [RFC5462] where only the label value is valid, and > >> > other fields (TC, S, and TTL) fields MUST be considered invalid. > >> > The Length MUST be set to 7. > >> > > >> > > >> > Previous versions of private draft uses 4 byte to store MPLS 20 > Bit label and ignores TC, S & TTL fields. > >> > >> The length in the previous version was 6, which was incorrect. The TLV > >> length is as per https://tools.ietf.org/html/rfc5440#section-7.1 > >> Which didnt make sense and your calculation below is correct! > >> > >> > But in IETF draft after TLV structure redefinition, total length > of the TLV becomes 7, i.e. BT(1 Byte)+Reserved(3 Byte)+MPLS 20bit Label(3 > Byte) = 7 Byte > >> > >> Yes > >> > >> > So, now MPLS 20 Bit Labelwill be stored in 3 byte. Is it correct? > >> > >> You can consider it a case of rounding up 20 bits to 3 bytes. > >> > >> > >> > If this is correct then I feel the wording of the above paragraph > needs to be more specific, meaning in 3 Byte Label there will be no space > for TTL, so > >> > my suggestion is to make below correction: > >> > > >> > BT = 0: The binding value is an MPLS label carried in the format > >> > > >> > specified in [RFC5462] where only the label value is valid, and > >> > other fields (TC, S, and TTL) fields MUST be considered invalid. > >> > The Length MUST be set to 7. > >> > > >> > >> My suggestion would be not mention any of the other fields and talk > >> only of 20 bits of Label. I see other SR RFCs take similar approach. > > > > > > Sounds Good. I'm agree with you. > > > >> > >> > > >> > 2. In some cases, a stateful PCE can request the PCC to allocate a > >> > > >> > binding value. It may do so by sending a PCUpd message containing > an > >> > empty TE-PATH-BINDING TLV, i.e., no binding value is specified > >> > (making the length field of the TLV as 2). A PCE can also make the > >> > request PCC to allocate a binding at the time of initiation by > >> > sending a PCInitiate message with an empty TE-PATH-BINDING TLV. > >> > > >> > > >> > As per new Binding TLV Structure below, BT is of 1 Byte and there > will be 3 Byte Reserved. > >> > > >> > 0 1 2 3 > >> > > >> > 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 > >> > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > >> > | Type | Length > | > >> > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > >> > | BT | Reserved > | > >> > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > >> > ~ Binding Value (variable length) > ~ > >> > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > >> > > >> > > >> > Now, an empty Binding TLV should have length of BT(1 Byte) + > Reserved (3 Byte) = 4 Byte instead of 2 Byte. > >> > > >> > So, I do not understand how in the draft it is calculated as 2 > Byte. Could you please give me some clue? > >> > >> > >> This seems to be an error IMHO. 4 seems to be correct. > > > > > > Okay. So what would be your suggestion to developer who is implementing > this draft? Should it be taken as 4? If draft needs correction > > when will that be published? > >> > >> > >> Thanks! > >> Dhruv > >> > >> > > >> > Thanks & Regards, > >> > Mrinmoy >
_______________________________________________ Pce mailing list [email protected] https://www.ietf.org/mailman/listinfo/pce
