Sounds like he means a VPS. Or a VPN to connect to the server.
A VPN is a 'Virtual Private Network'. In business, this is generally used for linking two remote work sites to appear on one network over the internet. Great for sharing internal servers without having to open up your firewall too much. Set them up right, and you've got kickass security too.
Generally online, a VPN is a means of very anonymously accessing the internet.
A VPS on the other hand, is a virtual private server. Essentially, a dedicated server - but it's running on virtual hardware. This hardware is virtualized by a big beefy server that has several VPSs running on it.
Sounds like your client wants to be able to connect to the server running all SEO tools, to check up on them.
Hope that helps - any other questions?