Internet connections - bandwidth limitations
To illustrate the difference between an internet link and a typical office Local Area Network (LAN), the scale diagram shows the relative sizes of these pipes, down which all network traffic must flow.
Nor does this apply only to the home user's connection. For a VPN back to the office, the company's own connection is also a vital factor.
Local Area Network connection
The green circle represents a typical Local Area Network (LAN) connection in the office, between a PC and its local servers at 1 Gbps (Gigabit/sec), or 1000 Mbps.
The amber circle, by contrast, shows a home worker's typical ADSL internet connection, which might have a download speed of 10 Mbps (Megabits/sec) – 100 times smaller.
The red circle - because ADSL is asynchronous - shows an upload speed of only 2 Mbps. This is important when saving files back to a server over a VPN.
Of course, some home connections are now larger than this, but many are smaller. What's available in any one place is something of a lottery.
To make the best use of the VPN connection, this performance difference between LAN and internet connections needs to be accommodated.