Re: [Bgp-autoconf] Short comparison of the different documents.

["Dongjie (Jimmy)" <[e-mail]>]

Hi Randy,

Thanks for your comments and the information about l3dl-ulpc draft. 

In general I agree the value of the attribute should be decided by an operator, and its meaning may be only understood by that operator. While as discussed it may be useful to define a specific attribute type for a set of use cases and describe the typical use cases in some document. The attribute values will not be standardized (at least not all of them).

Best regards,
Jie

> -----Original Message-----
> From: Randy Bush [mailto:[e-mail]]
> Sent: Wednesday, March 18, 2020 12:49 AM
> To: Dongjie (Jimmy) <[e-mail]>
> Cc: Jeffrey Haas <[e-mail]>; Warren Kumari <[e-mail]>;
> [e-mail]
> Subject: Re: [Bgp-autoconf] Short comparison of the different documents.
> 
> jimmy,
> 
> i was perhaps a little subtle.  i contend that the attributes are not decidable
> by anyone other than the op.
> 
> see Attribute List in draft-ymbk-lsvr-l3dl-ulpc
> 
> 3.  Upper Layer Protocol Configuration PDU
> 
>    To communicate parameters required to configure peering and operation
>    of Upper Layer Protocols at IP layer 3 and above, e.g., BGP sessions
>    on a link, a neutral sub-TLV based Upper Layer Protocol PDU is
>    defined as follows:
> 
>     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 = 9   |                 Payload Length                ~
>    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>    ~               |   ULPC Type   |   AttrCount   |               ~
>    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>    ~       Attribute List ...      |    Sig Type   | Signature Len ~
>    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>    ~               |                 Signature ...                 |
>    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
>    The Type and Payload Length are defined in [I-D.ietf-lsvr-l3dl].
> 
>    ULPC Type: An integer denoting the type of the uper layer protocol
> 
>    0     :  Reserved
>    1     :  BGP
>    2-255 :  Reserved
> 
>    The AttrCount is the number of attribute sub-TLVs in the Attribute
>    List.
> 
>    The Attribute List is a, possibly null, set of sub-TLVs describing
>    the configuration attributes of the specific upper layer protocol.
> 
>    An Attribute consists of a one octet Attribute Type, a one octet
>    Attribute Length of the number of octets in the Attribute, and a
>    Payload of arbitrary length up to 253 octets.
> 
>     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
>    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>    | Attr Type = 1 |    Attr Len   |            Payload            |
>    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+