Refer to the exhibit. The networking team configured segment routing in the network with a unique range of labels assigned to each router. However, the maintenance of the network is becoming more…

Question

Exhibit

Options

• ASet the same SRGB size on each node.
• BSpecify a custom prefix SID to distinguish each device.
• CDisable the default preservation.
• DSet the same SRGB on all routers.

• B
  3% (1)
• C
  3% (1)
• D
  94% (30)

Explanation

In Segment Routing with MPLS (SR-MPLS), each router has a Segment Routing Global Block (SRGB) - a reserved range of MPLS labels used for segment identifiers. A prefix SID is expressed as an index, and the actual label pushed by a given router is calculated as: label = SRGB_base + SID_index. When each router has a different SRGB (different base address and/or range), the same SID index maps to a different label value on every router. Every other router in the domain must therefore track each peer's unique SRGB to correctly compute label stacks along a path - a management burden that grows with every new router added. By configuring the same SRGB (same base and size) on all routers, a SID index always translates to the identical label value network-wide. This eliminates per-router SRGB tracking, simplifies label stack computation, and makes troubleshooting and capacity planning significantly easier.

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