LAN 'Local Area Network' - this is connecting your sites so you can share voice, video and e-mail, saving time and money. Which is safe and secure.
Using copper or fibre Ethernet Services to create your own network. In many cases you are probably already using in your office, this just makes it exclusive to your business.
Working from home? Today this means your office phone can be part of the office system. This means you could place a client on hold and transfer the call to accounts