This is the value to place in the RemainingLifeTime field of the LSPs we generate, and it should be at least 300 seconds greater than ciiSysMaxLSPGenInt. This is the lifetime stamped on this router's own self-originated LSPs -- once that many seconds elapse without a refresh, other routers purge the LSP and consider this router's advertised topology stale -- so it must comfortably exceed the refresh interval or the router's LSPs could expire in peer databases faster than they're refreshed. For example, with a default of 1200 seconds, this router's LSP is purged from a neighbor's database after 20 minutes of no refresh, which is why ciiSysMaxLSPGenInt is required to be at least 300 seconds shorter to guarantee refreshes always land in time.