To determine whether R1 is the DIS (Designated Intermediate System) in IS-IS, you analyze the LSDB (Link-State Database) output from the command:

bash

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display isis lsdb

In IS-IS, the DIS creates and advertises Pseudonode LSPs with the LSP ID format:

perl

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< system-id > . < 00-FF > . < 00 >

In the output shown:

scss

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0000.0000.0001.00-00* < — Normal LSP (R1)

0000.0000.0001.01-00* < — Pseudonode LSP (indicates R1 is DIS)

0000.0000.0002.00-00 < — Normal LSP (R2)

✅ The LSP 0000.0000.0001.01-00* is a Pseudonode LSP, and it belongs to R1 (0000.0000.0001). This LSP is only generated by the DIS on a broadcast network segment.

???? The presence of the Pseudonode LSP for R1 confirms that:

R1 is acting as the DIS.

The asterisk (*) next to the LSPs also means R1 owns them and they are local to R1.

✅ Final Answer: A. TRUE

Official Huawei Extract:

" In IS-IS, the DIS is responsible for generating a Pseudonode LSP on broadcast networks. The LSP ID of a Pseudonode ends with .01-00. The presence of this LSP in the LSDB confirms that the router is acting as the DIS. "

— [Huawei HCIA-Datacom Certification Guide – IS-IS Chapter: DIS and LSP Types]