Re: [lisp] multi-protocol support in RFC6830bis [ Was: RFC6830bis and multiprotocol support]

[Fabio Maino <[e-mail]>]

Thanks Dino.

Fabio


On 12/13/17 3:02 PM, Dino Farinacci wrote:
> After I go through Alberto’s response for RFC6833bis and one comment from Albert regarding RFC6830bis, I’ll document the P-bit and reference this spec in RFC6830bis. I plan to send email this week with both updates at one time.
>
> This should be the final updates to both specs. I’d like to request last call and possibly complete it before year-end. Is that possible chairs?
>
> Dino
>
>> On Dec 13, 2017, at 2:57 PM, Fabio Maino <[e-mail]> wrote:
>>
>> I have refreshed the LISP-GPE draft (https://tools.ietf.org/html/draft-lewis-lisp-gpe) to be bit-to-bit compatible with the data plane encoding in RFC6830bis, as discussed in the thread started on Nov. 29 (https://mailarchive.ietf.org/arch/msg/lisp/Dq18xxxQoDUkLX1Z_MCKaHZC1I4/?qid=a7da0673ad7ed2a161aa5f4334f96f19)
>> As a summary of the long thread:
>> - bit 5 is allocated as P-bit to indicate the presence of an 8-bit Next Protocol field
>>
>> - the Next Protocol field shares 8 bits with the Nonce/Map-Version field
>>
>> - when the P-bit is set, the Nonce/Map-Version features are still available with shorter (16-bit vs 24-bit) Nonce/Map-Version fields
>>
>> Thanks,
>>
>> Fabio
>>
>>
>> -------- Forwarded Message --------
>>
>> Subject:	[lisp] RFC6830bis and multiprotocol support
>> Date:	Wed, 29 Nov 2017 14:32:40 -0800
>> From:	Fabio Maino <[e-mail]>
>> To:	[e-mail] <[e-mail]>
>>
>> I would like to suggest a way to address mutiprotocol support in RFC6830bis, that may address what was discussed in Singapore.
>> This is based on using the last reserved bit in the LISP header as P bit to indicate support for multiprotocol encapsulation, as specified in the LISP-GPE draft (https://tools.ietf.org/html/draft-lewis-lisp-gpe)
>> The header, as specified in section 5.1, would look like:
>>
>>         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>>     L   |N|L|E|V|I|P|K|K|            Nonce/Map-Version/Next-Protocol    |
>>     I \ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>>     S / |                 Instance ID/Locator-Status-Bits               |
>>     P   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>>
>>
>> and the text in section 5.3 that reserves the 6th bit would be replaced by:
>>
>>     P: The P-bit is the Next Protocol bit. When this bit is set to
>>        1, the V-bit MUST be set to 0 and the Nonce length, when used, is
>>        limited to 16 bits. Refer to [draft-lewis-lisp-gpe] for more details.
>>        The P-bit is set to 1 to indicate the presence of the 8 bit Next
>>        Protocol field encoded as:
>>
>>       x x x 0 x 1 x x
>>      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>>      |N|L|E|V|I|P|K|K|           Nonce               | Next-Protocol |
>>      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>>      |                 Instance ID/Locator-Status-Bits               |
>>      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>>
>>
>> I will have to refresh the LISP-GPE draft, and reflect the allocations of the KK bits according to RFC8061 and Nonce. One of the K bits was used by LISP-GPE to indicate OAM packets, but that same functionality can be done using the Next-Protocol field.
>>
>> The use of the P-bit is not compatible with the Map-Versioning feature, but an equivalent function can be specified (if needed) with a Next-Protocol shim header. I can add text to the LISP-GPE draft to reflect that.
>>
>> This would address the multiprotocol working item included in the current charter.
>>
>> I can very quickly update the LISP-GPE draft to reflect this, but I wanted to hear what the group thinks first.
>>
>> Thanks,
>> Fabio
>>
>>
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