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Re: [Lsr] Enhancement related to Area Leader Sub-TLV

tony.li@tony.li Tue, 28 May 2019 15:20 UTC

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Sender: Tony Li <tony1athome@gmail.com>
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Date: Tue, 28 May 2019 08:20:50 -0700
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To: Huaimo Chen <hchen@futurewei.com>
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Subject: Re: [Lsr] Enhancement related to Area Leader Sub-TLV
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Hi Huaimo,


>     Before moving, each of N nodes may advertise an Area Leader Sub-TLV and a Dynamic Flooding Sub-TLV. After moving, only the leader node advertises a (Updated) Area Leader Sub-TLV.


The Area Leader sub-TLV should be advertised by all nodes that are candidates to being Area Leader.  Strictly speaking, you could choose only one, but that would become a single point of failure.  For simple redundancy, two seems a practical minimum, however it still seems somewhat risky due to the possible loss of an Area Leader after a multi-failure partition. Thus, it is likely that all N nodes will continue to advertise the Area Leader sub-TLV.

Since no sub-TLVs are withdrawn, there is no space savings.

Tony

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