In this passage, Ulysses tells Alcinous about what he has been doing after the Trojan War. The story that follows constitutes a flashback. The rest of Book IX is Ulysses recounting his adventures.
The technique used is flashbacks.The reason is that Ulysses sits and tells about his travelling adventures.This makes the narration richer as it gives examples of the resources Homer has as a poet . At the same time this technique makes the Odyssey more interesting and attractive for its readers.
