[CentOS] remote access info please

Hi ya'll,

I built a new CentOS 5.1 server for a client, housing a Lotus Notes / Domino
server, and various other virtualized IBM software server guests, and soon
will have to physically move that server to another distant location.

My question is that I will need secure access to those servers via X, not
just the C/L terminal. What do you recommend for a good secure CentOS
program which would do this. Would also want to access via a high port, but
I am sure just about any program will allow this to be manually configured.

Thanks for your help and input.

-- 
Regards,
Gary