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Pro tip: Don’t worry about older battery backups for modems and gateways
Providers used to be required to offer battery backup to support 911 calls using VoIP (voice over internet protocol) technology, but that’s now the customer’s responsibility. However, battery backup for your modem probably isn’t worth the hassle now. That’s because almost everyone uses a cell phone instead of VoIP these days. What’s more, the old backups supported only voice calls (not internet access), and a disaster bad enough to cause a power outage usually means you’ll have a widespread internet outage anyway.
If you still use VoIP and 911 backup gives you peace of mind, contact your provider to ask about purchasing battery backup or install your own backup power solution such as a long-lasting UPS.