Last time, we discussed new global DSL access options to Virtela Communications' Internet-based VPN services. Our discussion of the announcement with Virtela director of marketing Jeff Phillips led to an interesting discussion of WAN back-up strategies, because Phillips said one use of the new services is to back up leased-line access circuits.\u00a0While DSL provides redundancy from a service and equipment perspective, the dominant local phone company often provisions the DSL circuit and leased-line access links - and uses the same circuit to do so.\u00a0 If your site doesn't have dual-entrance facilities, and the same local carrier provisions your leased-line and DSL circuits, both links likely share a conduit. So a cut on one cable probably means a cut on the other. You might be better off with either an airborne connection - such as cellular or satellite - or a cable modem connection as a backup.Phillips said that Virtela will work with the phone company, as well as with competitive local-exchange carriers and interexchange carriers that have local facilities, to ensure physical diversity wherever possible.\u00a0 He also indicated that enterprises seem less open to alternative technologies like cable modem and wireless services for remote and branch offices than they are for teleworker environments.This correlates well with our findings in a Webtorials.Com survey conducted last July.\u00a0 Cable modem service, for instance, ranked slightly higher in customer satisfaction than DSL.\u00a0 However, it also ranked lower in terms of installation to remote and branch sites.Why?\u00a0 We wish we knew.\u00a0 The technology is solid and services are generally available.\u00a0 (If you want cable in your office for CNN and financial news, we bet you can get it.)\u00a0 Our best guess is a lack of business-targeted marketing by the cable companies.\u00a0What do you think?\u00a0 Let us know and we'll summarize the results in a later newsletter.