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I searched the web for answers, but I haven't found anything conclusive. What are the advantages/disadvantages of using an alternative DNS (for example, OpenDNS or Google DNS) as opposed to the default ISP DNS server?

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possible duplicate of Should I use Google Public DNS service for my desktop? – Oliver Salzburg May 15 '12 at 20:00
That question is strictly about google DNS, this is more general. – Tibi May 18 '12 at 13:11
up vote 6 down vote accepted
  • Open DNS has services related to their dns servers, such as phishing protection or parental controls, though you may have to sign up to configure them.

  • Selecting a server with better response time can speed up browsing

  • Open DNS now offers an encrypted DNS tool, which keeps anyone from seeing your DNS requests. No matter whose DNS servers you use, your ISP knows every webpage you visit, even if the webpage is SSL, the DNS request is not encrypted even though the connection to the website is SSL encrypted, so they came out with the tool to take care of that vulnerability.

So it can improve browsing speed and security, you may not get both depending on where you are.

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some advantages:

  • they can be more stable and not fall, when your provider fails

  • they could be more trustfull (your provider could redirect those "not found" to an advertising page, while the openDNS or Google DNS say they don't do that)

  • they could be faster (yes, your provider can be using a hardware that can't handle all the requests from their consumers)

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My provider blocks "potentially unwanted sites" with their DNS server. For example - there is some torrent trackers, which I unable to reach because they're banned at provider. Cheap trick, but it's the one of the reasons why I am using google open dns.

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You should be aware that multiple ISPs have signed agreements with various industry groups (RIAA i.e.) to warn users that access copy written materials and reduce the quality of the user's service if they do not comply with the warnings. Bypassing the ISP block these sites via DNS is most likely the first step down this path. – EBGreen May 15 '12 at 18:56
Not "access", but "downloading illegal content". merely visiting a site will not get you warned. So much dis-information. They have to determine it is illegal content and that you are downloading it before you get a… – Moab May 15 '12 at 19:46
That is why I said "users that access..." As I said it is just the first step. The fact that the ISP blocks the site should be considered an implicit warning. – EBGreen May 15 '12 at 20:00
I can access a file without downloading it, in most democratic countries it is illegal for an isp to block a website. Comcast got sued for just that, and lost. – Moab May 15 '12 at 20:14
That's true, block is not really the proper term. Not resolve the address would be more accurate. As far as I know no one has challenged that in court and since there are alternate name resolution services I don't think a challenge would get far. I'm not a lawyer and I'm not here for a legal argument. Simply wanted to let the poster know of a relatively recent development. – EBGreen May 15 '12 at 20:17

it all boils down to one thing: trust. if you do not trust the results of one 3rd party DNS-resolver you might want to pick a different 3rd party (eg. GoogleDNS or OpenDNS or etc etc) which claim that they do not fiddle with the results. and if you do not trust that 3rd party either, you could roll your own:

then you will get the real results from dns-root-servers.

the only reason to use the DNS-resolver of your ISP is to get the ip-addresses for some (ISP-intrinsic) services (VOIP settings come to mind). but with options like mara-dns or tinydns you could manage that as well (by asking the DNS of the ISP for certain domains).

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Disadvantages might be:

  • reduced privacy: another provider knows about your internet usage (eg. which websites you visit) Especially since Google is now joining data gathered from different services in users profiles, this might not be desired.

  • NXDOMAIN redirection (default setting for OpenDNS), causing unwanted effects like wrong DNS responses and redirects to unexpected websites.

Advantages might be:

  • able to circumvent censorship and undefeatable NXDOMAIN redirection on provider's DNS servers

  • perhaps more reliable/faster responses but YMMV

  • DNS based configurable content filtering and malware site protection (offered by OpenDNS)

Unless you have any issues with your ISP's servers I recommend to just stick with them. Manual configuration is more likely to break if something changes one day.

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There is no any disadvantage using 3rd parties DNS. Using ISP or 3rd party DNS all is same,, there is no encryption on dns request, even we use tunneling through SSH, TLS, SSL, Telnet, IPSec, etc, all is same..dns request is not encrypted.

dns is expose only our destination (request web) they can't take our data. they know only mr.A request go to facebook,, mr.B request go to torrent site.. what mr.A and mr.B do.. they don't know, becoz data is inside protocol, and security depend on what protocol you are used. security issue more correct adressed to our destination website, becoz that is where "our packet" delivered.

there is so many 3rd party dns out there, not only google and open dns, here some blog i found listing alot dns provider,, some of them is anonymous dns based several country,

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