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Change your DNS to avoid or bypass broadband 'outages' like Comcast's

Glenn Fleishman | June 5, 2015
Comcast had a massive "outage" on Monday that affected Seattle and the San Francisco Bay Area. Note that "outage" is in quotation marks, because the problem wasn't with the physical links that made up its broadband network, nor with routers that connect segments large and small. Instead, it was a bit of plumbing gone awry, like a faucet tap that can't be opened up, even though the pipes and water are all fine.

Comcast had a massive "outage" on Monday that affected Seattle and the San Francisco Bay Area. Note that "outage" is in quotation marks, because the problem wasn't with the physical links that made up its broadband network, nor with routers that connect segments large and small. Instead, it was a bit of plumbing gone awry, like a faucet tap that can't be opened up, even though the pipes and water are all fine.

Comcast had a DNS (Domain Name System) server failure in parts of the country. DNS is the glue that converts human-readable and -typeable names like "www.macworld.com" into the underlying Internet Protocol (IP) numbers used to initiate connections like 70.42.185.230 and 2607:f8b0:400a:805::1004. (The former is old-fashioned, original-flavor IPv4; the latter IPv6.)

It's a surprisingly important bit of connective tissue. While one can (tediously) enter numbers manually, they're subject to change, and many web servers are configured so that the name has to be sent as part of the request; this is what allows one piece of hardware or server software to handle multiple or even tens of thousands of different websites.

But you can take this into your own hands very simply. All computers and most mobile devices and routers let you point to DNS servers other than those provided by your ISP (Internet service provider). There are a few potential problems with this, but if the choice is between Internet and no Internet, there's no reason not to.

Choose an alternate and configure DNS

So-called public DNS providers offer DNS lookups that anyone can use. Switching to one requires a tiny bit of configuration, but no account or other arrangement with the service.

OpenDNS is the oldest of these, and it started at a time when ISP-run DNS servers were pokey as all get-out: it could take a second or even longer the first time your computer requested a given domain name to look up or resolve that name into an IP address. OpenDNS made web browsing seem faster by having zippy servers. The company now has an array of free-with-registration and paid add-on services for malware, threat protection, and network usage analysis. Its DNS servers are at 208.67.222.222 and 208.67.220.220.

Google's Public DNS followed later, and is just DNS and nothing more. It has the stylish numbers 8.8.8.8 and 8.8.4.4 for its DNS servers. (There are other public providers, but no reason I know of to shop around further.)

In the vast majority of network configurations, an IP address and other network settings are provided from a DHCP (Dynamic Host Configuration Protocol) server on a local network via a router to all devices that need Internet access. One or more DNS servers is set this way. However, you can override this.

 

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