Re: [Lsr] Discussion on draft-wang-lsr-hbh-process-00
Tony Li <tony1athome@gmail.com> Tue, 17 November 2020 17:40 UTC
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From: Tony Li <tony1athome@gmail.com>
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Date: Tue, 17 Nov 2020 09:40:51 -0800
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To: wangyali <wangyali11@huawei.com>
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Subject: Re: [Lsr] Discussion on draft-wang-lsr-hbh-process-00
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> Q1: are you using this information to determine the routing to the network? > On one hand, such advertisement does not effect on the normal SPF computation and may be useful for traffic engineering. For example, for IOAM service, if the HbH Processing Action of Node/Link is assigned to a slow processing plane, the Node or Link should be excluded for path computation. If the HbH Processing Action of Node/Link is ignore all extension Options header, the Node/Link can be used as the normal IPv6 transit node/link. If the HbH Processing Action of Node/Link is skip to Next extension Options header (e.g. Routing Header), the Node/Link can be considered as Endpoints in SRv6 routing. On the other hand, such advertisement is useful for entities to determine specific services encoded in HbH options header can be deployed in a given path. > > Q2: can you use the link color to compute paths? > In the above, I answered, taking advantage of this advertisement, the exact action taken by Node or Link to process HbH options header can be determined (defined in Action Flag field), which can be useful for traffic engineering. Hence, such advertisement is not only used to determine whether the HbH options header supported by Node/Link or not. But the link color cannot exactly indicate the exact action. This suggests that you’re missing one bit of information. Thus, could you use two link colors to differentiate between the two? Tony