[bess] Encoding a 20 bit label in a 24 bit field.

"Jakob Heitz (jheitz)" <jheitz@cisco.com> Mon, 15 October 2018 20:20 UTC

From: "Jakob Heitz (jheitz)" <jheitz@cisco.com>
To: BESS <bess@ietf.org>
Thread-Topic: Encoding a 20 bit label in a 24 bit field.
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Date: Mon, 15 Oct 2018 20:20:41 +0000
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Subject: [bess] Encoding a 20 bit label in a 24 bit field.
Precedence: list

We have proposed the following erratum for RFC 7432.

Opinions?

Regards,
Jakob.


-----Original Message-----
From: RFC Errata System <rfc-editor@rfc-editor.org> 
Sent: Friday, October 12, 2018 12:37 PM
To: Ali Sajassi (sajassi) <sajassi@cisco.com>; raggarwa_1@yahoo.com; nabil.n.bitar@verizon.com; aisaac71@bloomberg.net; uttaro@att.com; jdrake@juniper.net; wim.henderickx@alcatel-lucent.com; db3546@att.com; aretana.ietf@gmail.com; martin.vigoureux@nokia.com; Giles Heron (giheron) <giheron@cisco.com>; nabil.n.bitar@verizon.com
Cc: Krishnamoorthy Arumugham (karumugh) <karumugh@cisco.com>; l2vpn@ietf.org; rfc-editor@rfc-editor.org
Subject: [Technical Errata Reported] RFC7432 (5523)

The following errata report has been submitted for RFC7432,
"BGP MPLS-Based Ethernet VPN".

--------------------------------------
You may review the report below and at:
http://www.rfc-editor.org/errata/eid5523

--------------------------------------
Type: Technical
Reported by: Krishnamoorthy Arumugham <karumugh@cisco.com>

Section: 7

Original Text
-------------
Clarifications to following sub-sections:
Section 7.1
Section 7.2
Section 7.5


Corrected Text
--------------
Section 7.1:
Add below text to the section 7.1 regarding the encoding 
of MPLS label:

"The value of the 20-bit MPLS label is encoded in the 
high-order 20 bits of the 3 bytes MPLS Label field."

Section 7.2:
Add below text to the section 7.2 regarding the encoding
of both the MPLS label fields:

"The value of the 20-bit MPLS label is encoded in the 
high-order 20 bits of the 3 bytes MPLS Label field for
both MPLS Label1 and MPLS Label2."

Section 7.5:
Add below text to the section 7.5 regarding the encoding
of ESI Label fields:

"The value of the 20-bit MPLS label is encoded in the 
high-order 20 bits of the ESI Label field."


Notes
-----
MPLS label is a 20-bit value and is stored in a 3 bytes field in a packet. The 20-bit MPLS label value is generally stored in higher order 20 bits of the 3 byte label field. The exact encoding to be followed for storing MPLS label values are not explicitly mentioned in the RFC 7432 under section 7.1, 7.2 and 7.5 for different types of EVPN routes. This lead to ambiguity in different implementations. Hence a clarification is required.

Instructions:
-------------
This erratum is currently posted as "Reported". If necessary, please
use "Reply All" to discuss whether it should be verified or
rejected. When a decision is reached, the verifying party  
can log in to change the status and edit the report, if necessary. 

--------------------------------------
RFC7432 (draft-ietf-l2vpn-evpn-11)
--------------------------------------
Title               : BGP MPLS-Based Ethernet VPN
Publication Date    : February 2015
Author(s)           : A. Sajassi, Ed., R. Aggarwal, N. Bitar, A. Isaac, J. Uttaro, J. Drake, W. Henderickx
Category            : PROPOSED STANDARD
Source              : Layer 2 Virtual Private Networks
Area                : Routing
Stream              : IETF
Verifying Party     : IESG

[bess] Encoding a 20 bit label in a 24 bit field. Jakob Heitz (jheitz)
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Rabadan, Jorge (Nokia - US/Mountain View)
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Jeff Tantsura
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Zhuangshunwan
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Jakob Heitz (jheitz)
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Zhuangshunwan
Re: [bess] Encoding a 20 bit label in a 24 bit fi… John E Drake
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Tapraj Singh (tapsingh)
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Ali Sajassi (sajassi)
Re: [bess] Encoding a 20 bit label in a 24 bit fi… stephane.litkowski
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Acee Lindem (acee)
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Jakob Heitz (jheitz)
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Greg Mirsky
Re: [bess] Encoding a 20 bit label in a 24 bit fi… Ali Sajassi (sajassi)