JNCIS-ENT: Juniper Networks Certified Specialist – Enterprise Routing and Switching (2025) — Question 45

Which statement is correct about the IS-IS ISO NET address?

Answer options

• A. An ISO NET address defined with a system ID of 0000.0000.0000 must be selected as the DIS.
• B. An ISO NET address must be unique for each device in the network.
• C. You can only define a single ISO NET address per device.
• D. The Area ID must match on all devices within a L2 area.

Correct answer: B

Explanation

The correct answer is B because an ISO NET address must indeed be unique for each device to avoid conflicts within the network. Option A is incorrect as the system ID of 0000.0000.0000 does not have to be the DIS. Option C is wrong because it is possible to configure multiple ISO NET addresses for certain devices. Option D is also incorrect as while it's good practice for Area IDs to match, it's not a strict requirement for all devices in the L2 area.