This is the priority for becoming LAN Designated Intermediate System at this level. On a broadcast circuit, this value determines which router wins the DIS election for that level, since the DIS is responsible for generating the pseudonode LSP and periodic CSNPs for the segment, so raising this on a router more capable or stable than its LAN neighbors deliberately steers the election in its favor. For example, setting this to 127, the maximum, on the most capable and stable router on a shared LAN segment makes it consistently win DIS election over neighbors left at the default priority.