OpenDNS

OpenDNS

Type	DNS Resolution Service
Founded	2005
Headquarters	San Francisco, California
Key people	David Ulevitch (Founder & CEO)
Employees	20[1]
Website	OpenDNS.com

OpenDNS is a DNS (Domain Name System) resolution service. OpenDNS extends DNS adding features such as misspelling correction, phishing protection, and optional content filtering. It provides an ad-supported service^[2][3] "showing relevant ads when we [show] search results" and a paid advertisement-free service.

OpenDNS provides the following recursive nameserver addresses^[4] for public use, mapped to the nearest operational server location by anycast routing:

• 208.67.222.222 (resolver1.opendns.com)
• 208.67.220.220 (resolver2.opendns.com)
• 208.67.222.220 ^[4]
• 208.67.220.222 ^[4]

OpenDNS also provides the following recursive nameserver addresses as part of their FamilyShield^[5] parental controls which block pornography, proxy servers, phishing sites and some malware:

• 208.67.222.123
• 208.67.220.123

IPv6 addresses (experimental)^[6]

• 2620:0:ccc::2
• 2620:0:ccd::2

Services

OpenDNS offers DNS resolution for consumers and businesses as an alternative to using their Internet service provider's DNS servers. By placing company servers in strategic locations and employing a large cache of the domain names, OpenDNS can process queries more quickly.^[7] DNS query results are sometimes cached by the local operating system or applications, so this speed increase may not be noticeable with every request but only with requests that are not stored in a local cache. OpenDNS has adopted and supports DNSCurve.^[8]

Other features include a phishing filter, domain blocking and typo correction (for example, typing "example.og" instead of "example.org"). By collecting a list of malicious sites, OpenDNS blocks access to these sites when a user tries to access them through their service. OpenDNS also launched PhishTank, where users around the world can submit and review suspected phishing sites.

The name OpenDNS refers to the DNS concept of being open, where queries from any source are accepted. It is not related to open source software; the service is based on closed-source software.^[9]

OpenDNS earns a portion of its revenue by resolving a domain name to an OpenDNS server when the name is not otherwise defined in DNS. This has the effect that if a user types a nonexistent name in a URL in a web browser, the user sees an OpenDNS search page. Advertisers pay OpenDNS to have advertisements for their sites on this page. While this behavior is similar to VeriSign's previous Site Finder or the redirects many ISP's are placing on their own DNS servers, OpenDNS states that it is not the same, as OpenDNS is purely an opt-in service (compared to Site Finder's effect on the entire Internet, as VeriSign is an authoritative registry operator)^[10] and that the advertising revenue pays for the customized DNS service.^[11]

One example of such an added service was the company's April 22, 2007 launch of "shortcuts",^[12] letting users make custom DNS mappings, such as mapping "mail" to "mail.yahoo.com". This feature launch was covered by a large number of publications, including the New York Times,^[13] Wired,^[14] and PC World.^[15] Unfortunately, due to browser compatibility and other issues, this service has been discontinued.^[16]

On May 13, 2007, OpenDNS launched a new domain blocking service which provides the ability to block/filter web sites visited based upon categories. This allows corporate, educational and parental control over the type of sites that may be accessed. On August 9, 2007 OpenDNS added the ability to override the filter through individually managed blacklists and whitelists. On February 20, 2008 in an effort to make their domain block list current with new website additions, OpenDNS changed from a closed list of blocked domains to a community driven list whereby individual OpenDNS subscribers can suggest sites for blocking. If a sufficient number of other subscribers concur with the categorization of the site it is added to the appropriate category for blocking. The threshold of votes required to add a new site to the filter has not been disclosed. Over 50 categories now exist for categorizing websites providing for fine grained control over web browsing habits. The basic OpenDNS service does not require a sign up, but using the block/filter feature requires the user to create an account and log in to a dashboard.^[17]

On December 3, 2007, OpenDNS began offering DNS-O-Matic, a free service, to provide a method of sending dynamic DNS (DDNS) updates to several DDNS providers using DynDNS's update API.^[18]

On October 21, 2009, OpenDNS launched OpenDNS premium services, for small businesses and enterprises with advanced needs. The service offers ad-free result pages, increased reporting and block features, and other services. Pricing for the Enterprise version starts at $2000 per year.^[19] The deluxe version, more customisable than the free-of-charge basic version and free of advertisements, costs $9.95 per year for families and $5.00 per user per year for businesses, schools and organizations.^[19]

As of March 2010 OpenDNS handles over 20 billion DNS requests daily, with over 26 billion being delivered on 21 April, 2010. ^[20]

History

• In July 2006, OpenDNS was launched by computer scientist and entrepreneur David Ulevitch. It received venture capital funding from Minor Ventures, which is led by CNET founder Halsey Minor.

• On July 10, 2006, the service was covered by digg, Slashdot, and Wired News, which resulted in an increase of DNS requests from just over one million requests on July 9 to 30 million on July 11.^{[citation needed]}

• Before 2007 OpenDNS was using the DNS Update API from DynDNS to handle updates from users with dynamic IPs.^[21]

• On October 2, 2006, OpenDNS launched PhishTank, an online collaborative anti-phishing database.

• On June 11, 2007, OpenDNS started advanced web filtering to optionally block adult content for their free accounts.

• On November 5, 2008, Nand Mulchandani, former head of VMware's security group, left VMware to join OpenDNS as new CEO, replacing founder David Ulevitch, who remained as the company's chief technology officer.^[22]

• In July 2009, OpenDNS was funded by Sequoia Capital and Greylock.^[23]

• In November, 2009 David Ulevitch resumed his post as CEO of OpenDNS.

• In June 2010, OpenDNS launched "FamilyShield", a service designed to filter out sites with pornographic content. The service uses the DNS addresses 208.67.222.123 and 208.67.220.123.^[24]

• On September 1, 2010, the World Economic Forum announced the company as a Technology Pioneer for 2011.^[25]

• On November 8, 2011, Founder and CEO David Ulevitch wrote an open letter to Congress about the Stop_Online_Piracy_Act and the Protect IP Act.^[26]

Privacy issues, conflicts and Google redirection

While the OpenDNS name resolution service is free, peoplewho have complained about how the service handles failed requests. If a domain cannot be found, the service redirects users to a search page with search results and advertising unless the user has paid for an upgraded service. Users can switch this off via the OpenDNS Control Panel, or specify another page to use for missing domains. This behavior is similar to that of many large ISPs who also redirect failed requests to their own servers containing advertising. ^[27]

In 2007, David Ulevitch explained that in response to Dell installing "Browser Address Error Redirector" software on their PCs, OpenDNS started resolving requests to Google.com. Some of the traffic is handled by OpenDNS typo-correcting service which corrects mistyped addresses and redirects keyword addresses to OpenDNS's search page, while the rest is transparently passed through to the intended recipient.^[28]

Also, a user's search request from the address bar of a browser that is configured to use the Google search engine (with a certain parameter configured) may be covertly redirected to a server owned by OpenDNS without the user's consent (but within the OpenDNS Terms of Service).^[29] Users can disable this behavior by logging in to their OpenDNS account and unchecking "OpenDNS proxy" option.^[30] Additionally, Mozilla users can fix this problem by installing an extension^[31] or by simply changing or removing the navclient sourceid from their keyword search URLs.

This redirection breaks some non-web applications which rely on getting an NXDOMAIN for non-existent domains, such as e-mail spam filtering, or VPN access where the private network's nameservers are consulted only when the public ones fail to resolve.

Server locations

• Amsterdam, The Netherlands
• Chicago, Illinois, USA
• Dallas, Texas, USA
• Frankfurt, Germany
• London, England, United Kingdom
• Los Angeles, California, USA
• Miami, Florida, USA
• New York, New York, USA
• Palo Alto, California, USA
• Seattle, Washington, USA
• Singapore
• Washington, DC, USA

See also

• Google Public DNS
• NortonDNS
• DNS Advantage

References

1. ^ "> About Us > Management". OpenDNS. http://www.opendns.com/who. Retrieved 2011-08-21. 
2. ^ July 26, 2007 (2007-07-26). "OpenDNS is a free, ad-based service". Pcmag.com. http://www.pcmag.com/article2/0,2817,2163029,00.asp. Retrieved 2011-08-21. 
3. ^ "OpenDNS > > We make money just like Google and Yahoo". http://www.opendns.com/how/free/how-can-opendns-be-free/. Retrieved 2011-08-21. 
4. ^ ^{a b c} "OpenDNS > Support > Knowledge Base > Additional (3rd and 4th) OpenDNS Addresses". OpenDNS. http://www.opendns.com/support/article/115. Retrieved 2011-09-21. 
5. ^ "OpenDNS Parental Controls". OpenDNS. http://www.opendns.com/home-solutions/parental-controls/. Retrieved 2011-11-08. 
6. ^ OpenDNS IPv6 Sandbox
7. ^ "OpenDNS: What's Your Take?". Neowin.net. 2007-03-13. http://www.neowin.net/index.php?act=view&id=38726. Retrieved 2010-04-20. 
8. ^ "OpenDNS adopts DNSCurve, official OpenDNS blog entry". Blog.opendns.com. http://blog.opendns.com/2010/02/23/opendns-dnscurve/. Retrieved 2011-08-21. 
9. ^ OpenDNS | 0x80
10. ^ "OpenDNS knowledge base: OpenDNS is not like Site Finder". Opendns.com. http://www.opendns.com/support/article/29. Retrieved 2010-04-20. 
11. ^ "OpenDNS knowledge base: How does OpenDNS make money?". Opendns.com. http://www.opendns.com/support/article/14. Retrieved 2010-04-20. 
12. ^ "OpenDNS Blog, shortcut the web". Blog.opendns.com. http://blog.opendns.com/2007/04/22/shortcut-the-web/. Retrieved 2010-04-20. 
13. ^ Pogue, David (2007-04-24). "NYT, A shortcut to your web destination". Pogue.blogs.nytimes.com. http://pogue.blogs.nytimes.com/2007/04/24/a-shortcut-to-your-web-destination/. Retrieved 2010-04-20. 
14. ^ Wired, OpenDNS offers keyword browsing shortcuts^{[dead link]}
15. ^ "PCworld, OpenDNS adds browser shortcuts to free service". Blogs.pcworld.com. 2007-04-23. http://blogs.pcworld.com/staffblog/archives/004202.html. Retrieved 2010-04-20. 
16. ^ "Shortcuts". OpenDNS Knowledgebase. http://www.opendns.com/support/article/123. Retrieved 27 September 2011. 
17. ^ "How to Protect your Kids Online using OpenDNS". PCTechNotes. 2009-03-17. http://pctechnotes.com/how-to-protect-your-kids-online-using-opendns/. Retrieved 2011-08-22. 
18. ^ "OpenDNS Announces DNS-O-Matic: Free Service to Simplify Residential ISP and Small Businesses' Dynamic DNS Service". Prweb.com. http://www.prweb.com/releases/2007/12/prweb573680.htm. Retrieved 2010-04-20. 
19. ^ ^{a b} "> Use". OpenDNS. http://www.opendns.com/start/. Retrieved 2010-04-20. 
20. ^ OpenDNS stats.
21. ^ "> Support > Knowledge Base > Dynamic IP: General Info". OpenDNS. http://www.opendns.com/account/dynamic_dns.php. Retrieved 2010-04-20. 
22. ^ "VMware security chief leaves to run OpenDNS". Computerworld.com.au. 2008-11-21. http://www.computerworld.com.au/article/268359/vmware_security_chief_leaves_run_opendns. Retrieved 2010-04-20. 
23. ^ Arrington, Michael. "Sequoia, Greylock Take Stake In OpenDNS", TechCrunch, July 7, 2009, accessed February 4, 2011.
24. ^ "Introducing FamilyShield Parental Controls". OpenDNS. 2010-06-23. http://blog.opendns.com/2010/06/23/introducing-familyshield-parental-controls/. Retrieved 2010-09-19. 
25. ^ Thirty-One Visionary Companies Selected as Technology Pioneers 2011
26. ^ Open Letter from OpenDNS to Congress about SOPA and PROTECT IP
27. ^ http://nxr-opt-out-trial.comcast.net/ Comcast Domain Helper Service
28. ^ David Ulevitch. OpenDNS Blog » Google turns the page... in a bad way. May 22, 2007. Retrieved 2008-07-04.
29. ^ Amit Agarwal Prevent OpenDNS from Redirecting Google Search Queries, March 21, 2008, Digital Inspiration. labnol.org. Retrieved 2008-07-04.
30. ^ "Is OpenDNS running a proxy?". Opendns.com. 2009-03-17. http://www.opendns.com/support/article/111. Retrieved 2011-10-09. 
31. ^ I'm Feeling Lucky Problem Fix for OpenDNS users, July 3, 2008.

External links

• OpenDNS website
• Review at CNET
• Review at PCMag