[Pce] Comments about the LSP Object Flag field

<xiong.quan@zte.com.cn> Mon, 16 September 2019 08:42 UTC

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Subject: [Pce] =?utf-8?q?Comments_about_the_LSP_Object_Flag_field?=
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Hi all,




As defined in [RFC8231], the length of LSP Object Flag field is 12 bits and it defined the value from bit 5 to bit 11.  

The bits from 1 to 3 are defined in [RFC8623] and the bit value 4 is used in [RFC8281]. So all bits of the flag has been occupied as the following shown.









I noticed many other drafts have extended the flag, for example, draft-li-pce-sr-path-segment defined a new P bit.

But no unused bit can be assigned for it. So I propoese  a new LSP-EXTENDED-FLAG TLV for LSP object to extend the

 length of the flag as the following shown.

        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=TBD             |                    Length                   |

       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

       |                                    Extended Flag                                         |

       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+




What is ypur opnion? Do you have other suggestions?





Thanks,

Quan