The new standard of the Interystem Alliance.
I based this one more of the UN flag.
The 4 stripes represent the 4 key elements of the government, the President (outermost stripe), the Judiciary (the second outermost stripe) and the two houses of the legislature (the Senate and the Council of Lords - the two broken stripes).
The olive branches are a carry over from the UN flag (which served both the first and second UN), representing a new era of peace and cooperation. The two octagon rings represent the original sixteen member nations (13 star systems with sol having 3 member worlds and Centauri having 2 member worlds).
The eight pointed stars represent the 8 cardinal directions in interstellar travel (Galactic North, Galactic North East, Galactic East, etc. - relative to the core of the galaxy with the perpendicular being a line through the galactic core through earth referred to as the "Terran Line"