Spectrum 2 is an XMPP transport/gateway and XMPP server. It allows XMPP users to communicate with their friends who are using one of the supported networks. It supports a wide range of different networks such as ICQ, XMPP (Jabber, GTalk), AIM, MSN, Facebook, Twitter, Gadu-Gadu, IRC and SIMPLE. Spectrum is written in C++ and uses the Swiften XMPP library and different libraries for legacy networks. Spectrum 2 is open source and released under the GNU GPL2+ license.
Spectrum 2 frontends and backends
As it was already written above, Spectrum 2 supports multiple IM networks. Spectrum 2 distinguishes between Frontend and Backend networks.
If some network is supported as Frontend, it means that Spectrum 2 allows its users to use this network to communicate with other users using the backend network.
If you for example use Slack as a frontend and IRC as a backend, the Spectrum 2 users can add Spectrum 2 to their Slack team, join the IRC network and communicate with their friends on IRC network.
Currently, following frontends are supported: