lets say during halo 3 co op you have very fast internet and the other guy

[Justin]

has very slow internet speed? who will the game lag for if the fast internet is hosting the match and the slow speed is joining the match

and the opposite who will lag if the fast speed is joining and the slow speed is hosting

and do i need more speed this is what i have
download
1645 kbps
upload 423 kbps
if necessary i could upgrade my speed to download
8 mbps

upload
768 kbps

or the fastest i could get but costs more
download 12 mbps
upload 1.5 mbps

 

[that guy]

the game will lag on both ends...