if you're connecting to an IP address - this should be transparent.

when a failover happens, the backup takes ownership of the VIP address as part of the process of it becoming a primary, you can find out more details in the documentation - here

I've posted the 'Clustering options for high availability and scalability' slides on SlideShare  (here)

@Sven,

Caché does not support outgoing NTLM authentication, EWS will have to be configured to allow basic authentication which in turn allows Caché to provide a username/password from that domain.

The connection can be made more secure by requiring TLS prior to transmission or requiring client certificate authorization.

Oren