Your best bet is to use a dynamic DNS service to allow your customer's employees to find his server. Your customer's server will run a small program or script that reports IP address changes to the dynamic DNS server, ensuring that DNS always has up-to-date information.
There are several dynamic DNS providers offering services for free or a nominal fee. If your customer doesn't already have a domain and doesn't want to get one, some services, such as DynDNS, will provide one for him.
Related Q&A from Retired Expert - Jon Snader
Learn how to set an IP address on the network interface of a FTP/Web/mail server when a client has only one public IP address.continue reading
To connect to a WAN remotely, your client can use a VPN client or a leased line. Learn the pros and cons of WAN connectivity with each option, such ...continue reading
When using ISA 2000, some users can lose connection to the network and experience packet loss even if the VPN client is still connected. Learn how ...continue reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.