SMTP Servers

Hi there - I'm trying to find the current SMTP server addresses, as it appears the one I used in the past (smtp.HMC1.comcast.net) has gone away.  In reading the forums, it also appears there may be some new setup required for a static IP to enable SMTP relay beyond the authentication and TLS layer - I searched for guidance documentation and found none.  Appreciate if anyone has pointers to the relevant info.