Ok here is what I took from it after some background checks: LF.Xx.3723 is the codename for the Flood Cell type Delta site is Installation 5 (from Halo 2) 2401 Penitent Tangent is the AI (Oracle) of Installation 5 However, here's the catch: Based on records found in the Halo 3 terminals, the flood broke free from containment on Installation 5 in the year 2273 Halo 3 took place in the year 2552 The time reported in the log is roughtly 286.79 years Therefore, the containment log reported another breach in the year 2559.79, roughly 7 years after the Arc was destroyed. This leaves open one of two possibilities: 1.) The Smuggler (codename for the new Halo 3 Map) is simply just a map based on Installation 5 in a flood-ruined Forerunner structure or on a bigger stretch... 2.) The foundation for the next game. The Halo installations remaining after the destruction of the Arc lay completely barren and forgotten. When Halo 2 ended, Installation 5 was overrun with the Flood, but it was believed that with the death of the Gravemind in Halo 3, the Sentinels on Installation 5 would then be able to take care of the contamination. However, this was never addressed. Maybe the Flood were forced back into containment, until someone else came and released them again. This would also fit the whole "It could be a while before anyone finds us, years even" quote by Cortana in the closing scene of Halo 3, and it does fit the magic "7" number Bungie loves so much. The planet in the end looks like it is Forerunner, possibly Onyx, and now the flood could be back again, 7 years in the future, trying to save themselves from the remaining 6 rings that could possibly still be individually activated, and therefore look towards Onyx for shelter.