Both IBM Lotus and Microsoft have introduced federation between their EIM systems and some of the public IM networks so that employees may use one interface to both their internal EIM system and their contacts on AOL , MSN , and Yahoo !
Since then , both IBM Lotus and Microsoft have introduced federation between their EIM systems and some of the public IM networks thus employees may use a single interface to both their internal EIM system and their buddies on AOL , MSN , and Yahoo !