In instant messaging, federated IM networks are those that allow communications across different IM clients and platforms, similar to the way e-mail allows people to communicate regardless of which e-mail client they choose to use. Federated IM networks are those which maintain an open directory that allows other IM networks to message their users.
Many federated IM networks communicate using an open standard, such as Jabber/XMPP. IM Networks using XMPP provide open communications with other XMPP-based networks. Some federated networks work on the basis of interoperability where the software from two or more vendors share data between the different proprietary platforms.