How do I connect from a machine with a dynamic IP address?

This is not possible for the moment! For example, a personal PC with a dynamic IP address, connected via an ADSL liaison, cannot be integrated into the IDRIS filters.

There is a way to circumvent this problem:
If you can access a machine in your laboratory (static IP address) which is registered in the IDRIS filters, the account will be open by passing through this intermediary host and you can connect to the Adapp pre/post-processing front-end machine, or the front-end machines of the Ada and/or Turing computers.
In this way, you can work on the Adapp pre/post-processing machine, or on an IDRIS computing machine (Ada, Turing) (through a multi-hop SSH).