Backup your ADSL or ISDN
If you rely on your Internet connection, you can overcome an ADSL failure by adding the DrayTek AFM-102 dial-up backup to your Vigor 2820. Dial-up backup uses a 'good old-fashioned' analogue modem to dial a backup ISP if your ADSL line or ISP fails, either temporarily or for an extended period. The add-on analogue modem provides 'V92' connections (up to 52000bps downstream speed) which is somewhat slower than your broadband connection but suitable for light web browsing, email and all other essential online activities.
The DrayTek Vigor 2820 will detect when your ADSL connection fails and automatically activate the dial-up connection using the AFM-102 modem which is connected to the router's USB port. Once ADSL service is restored, the router will hang-up the dial-up connection.
There are lots of 'free' dial-up ISPs in the UK which you can use in an emergency or occasional use without subscription; you pay only for the call costs (normally 0845 Lo-Call Rate). Alternatively, you can subscribe to an ISP that offers dial-up calls that are free of charge, for a monthly subscription.
Analogue Dial-Up on its own
As well as backup to your ASDL connection, you can use a dial-up connection permanently without an ADSL line. This is ideal for shared Internet access, or wireless access to the Internet in temporary locations where an ADSL line isn't available, and an alternative to the 3G modem solution also available on the Vigor 2820.