Re: [mpls] [Bier] [bier] The first nibble issue associated with MPLS encapsulation

Stewart Bryant <stewart.bryant@gmail.com> Thu, 14 April 2016 19:36 UTC

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To: Loa Andersson <loa@pi.nu>, "Nagendra Kumar Nainar (naikumar)" <naikumar@cisco.com>, Eric C Rosen <erosen@juniper.net>, Alexander Vainshtein <Alexander.Vainshtein@ecitele.com>
References: <1FEE3F8F5CCDE64C9A8E8F4AD27C19EE0D53871C@NKGEML515-MBX.china.huawei.com> <B664DB14-0A8C-4437-83E3-F9DA6C0DDA61@cisco.com> <mc51yrrf9n0wxbjsrprt9amf.1460143890063@email.android.com> <CA+RyBmXpZ-Kt77TW-=_kPYmahdw_yUHB5xhy8YtYVq2OcRJxbA@mail.gmail.com> <D32DB725.3F57B%cpignata@cisco.com> <CA+RyBmW+qonpScnLOfsGorayCvsS0vrFcn+o5nPvOqCOv9Jc3g@mail.gmail.com> <AM3PR03MB0775C55E5AD3247F373007139D940@AM3PR03MB0775.eurprd03.prod.outlook.com> <570BB266.8090608@juniper.net> <570F6374.6030406@gmail.com> <DB3PR03MB0780B7CE7B96283FB484C2489D970@DB3PR03MB0780.eurprd03.prod.outlook.com> <570F9901.2080406@juniper.net> <D3352203.13D10A%naikumar@cisco.com> <570FB333.5080509@pi.nu>
From: Stewart Bryant <stewart.bryant@gmail.com>
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Date: Thu, 14 Apr 2016 20:36:22 +0100
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Subject: Re: [mpls] [Bier] [bier] The first nibble issue associated with MPLS encapsulation
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On 14/04/2016 16:11, Loa Andersson wrote:
>
>
> /Loa
>
> On 2016-04-14 22:41, Nagendra Kumar Nainar (naikumar) wrote:
>> Hi,
>>
>> Per IANA registry, 0-1 are ³Reserved² and so is not strictly assigned 
>> with
>> PW. Something like a modified CW beneath LSE?. Further, BIER is 
>> hop-by-hop
>> lookup based. So I think we don¹t need to include this always. 
>> Instead, we
>> could conditionally include this, if the next BFR is tunneled (not
>> directly connected).
>>
>> The receiving node will use the label to identify the payload/FEC. So I
>> think, the presence of modified CW should not confuse it with PW.

Not quite Loa.

It could be an Ethernet PW with no CW.

Stewart