Choosing a VPN network design that best fits the needs of your business is essential. Some client maintenance is required. No client maintenance is required. Network is more scalable with digital certificates than with pre-shared keys. You can configure unlimited clients.
Network is less scalable with pre-shared keys than with digital certificates.
Router must be reconfigured with each additional client. One workaround is to use wildcard pre-shared key. Scalable to larger networks. Client creates a VPN over PSTN and Internet using IPSec. PSTN is not secured.