node-xmpp-bosh: A BOSH (connection manager) session manager for the XMPP protocol

You can find out all about what BOSH is from XEP-0124 and XEP-0206.

Most respectable XMPP servers out there such as Openfire, Ejabberd, and Tigase support BOSH as part of the server.

This is where you can download the node-xmpp-bosh BOSH server from.
node-xmpp-bosh has a new home at github!

I'll just discuss some of the reasons that it's good to have a BOSH session manager running outside of the XMPP server.

1. Easier to scale the BOSH server and the XMPP server independently (independently being the key here). See my previous blog post for a detailed explanation
2. You can support users from multiple domains such as gmail.com, chat.facebook.com, jabber.org, pandion.im, etc... using the single BOSH server
3. Any customizations to the BOSH server are easier made if it is running out of process (restart it independently of your XMPP server - since getting an XMPP server warmed may be more expensive than getting a BOSH server warmed up)
4. Use protocols other than XMPP at the back, but still retain the same interface as far as clients are concerned. This will still require you to use XMPP for the actual communication (Note: This can be accomplished via transports [for yahoo, msn, aim, etc...] available for any XMPP server [that supports XEP-0114] as a Jabber Component). But, if you please, you can also write a small drop-in replacement server that speaks basic XMPP, but does something entirely bizarre at the back!!