In this work we present a class of geometries which describes wormholes in a
Randall-Sundrum brane model, focusing on de Sitter backgrounds. Maximal
extensions of the solutions are constructed and their causal structures are
discussed. A perturbative analysis is developed, where matter and gravitational
perturbations are studied. Analytical results for the quasinormal spectra are
obtained and an extensive numerical survey is conducted. Our results indicate
that the wormhole geometries presented are stable.Comment: 10 pages, 7 figure