Apple TV streaming can be hindered by Google DNS
According to Maller's theory, Akamai is able to obtain the correct geography information and accurately route you through the closest server when you use your ISP's DNS settings. If you subvert this process using a third-party DNS service, then the routing from Akamai may be less than optimal. It may even route everyone through the same pipes which causes congestion and slows down streaming. While this intuitively makes sense, Maller only provides anecdotal evidence to support this theory. Until more evidence surfaces, I would not go around telling everyone they need to ditch OpenDNS or GoogleDNS. Nonetheless, this possible DNS effect is something to store in the back of your mind as changing your DNS is potentially a quick and easy solution if you are having difficulties while streaming Apple TV rentals.
[Via ZDNet]
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If you are experiencing problems with streaming video on your Apple TV, you may want to take a closer look at your DNS settings, according...
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several months ago I had trouble loading gmail webpages so I switched the dns to google dns and problem solved two days ago I could not load the apple website or iTunes so I switched back to my ISP dns and problem solved. apple and google having a go at each other?
December 22 2010 at 5:28 PM Report abuse Permalink rate up rate down ReplyI was having some problem with my isp's dns servers abut a week back incidentally about 2 days beforewhen I got my apple tv 2 and I the download speeds on apple tv 2 were pathetic it sometimes took over 30 mins for tv show to start and then I read this article and switched back to isp's dns server and the tv show started instantly. So I guess this article has some truth to it.
December 22 2010 at 12:27 PM Report abuse Permalink rate up rate down ReplyNetMage, eh? Then what part of #1 and #2 above you didn't understand? ;-)
Once your computer has established a connection to a site (any site) what the remote site sees is your IP address, not the IP address of your DNS (which is not transmitted at any stage). Please, get your facts right -- IP-based geolocation is based on the IP address assigned by your ISP.
RT.
Your IP address is not used for the geolocation. When you switch DNS servers, different IP addresses for the Akamai servers are being returned. That's why I used traceroute to determine where the IP was located. There are different IP addresses stored in different DNS services for the Akamai records. That's how it generally aggregates traffic by region. The assumption is that you use the ISP's server's that will be physically nearby.
December 21 2010 at 2:08 PM Report abuse Permalink rate up rate down ReplyKevvo, your IP address *is* used for geolocation: http://en.wikipedia.org/wiki/Geolocation.
Whether Akamai is using it or not is a different issue altogether, but I hope they're not so naive to use whatever server has been assigned by a DNS lookup rather than figure by themselves the best one to stream content to your computer, ESPECIALLY BECAUSE resolving a site like www.apple.com (which ultimately seems to translate to e3191.c.akamaiedge.net) returns three different IP addresses depending on wheter I use my ISP's, Google's or OpenDNS's DNS -- and there could be plenty of valid reasons not to use my ISP's.
RT.
Yves, sorry but you are the one who doesn't understand the problem:
1) There is no way for anyone to know what your DNS settings are: www.tuaw.com is looked up in the current DNS, which returns an IP address which, in turn, it's used to connect to this site. Once the connecton is done the DNS plays no further role whatsoever and the remote site has no knowledge about it.
2) IP-based geolocation is done by looking up your IP address, usually in the WHOIS database.
There's plenty of information available on the subject, so there is no need to take anyone's word as the gospel.
RT.
You shouldn't talknabout stuff you don't understand, like DNS resolution. Do you think your DNS server stores the address of every name in the world?
DNS is a distributed system - when your DNS server needs to resolve an Akamai name, it asks the root servers for the relevant name server, which is owned by Akamai. It then asks the Akamai server for the name resolution, and Hey Prsso! Akamai knows the IP address of your DNS server, and can use this to modify the resolution to distribute traffic.
Guys, guys, guys... the DNS you are using has nothing to do with the IP address seen by the site you are connecting to.
That is, if A establishes a connection to B, A's DNS obtains the IP address of B and, conversely, is B's DNS that returns A's IP address -- that's why you need a proxy or, even better, a VPN in some other country to make it appear you are using a different IP address (think about location restricted services like Pandora or Hulu).
But the best part is that you don't have to take my word (or anyone else's) for it, just change your DNS to Google's or OpenDNS and visit a site like http://whatismyipaddress.com/ and see for yourself.
RT.
I think you just don't understand the problem. Nobody say that your IP change, the problem is the redirection to a different akamai server that may be a few hops away than the one you get if you use your isp dns.
December 21 2010 at 7:23 AM Report abuse Permalink rate up rate down ReplyThis articles title is very misleading. It should be "Apple TV streaming can be hindered by Thirdparty DNS"
December 20 2010 at 10:28 PM Report abuse Permalink rate up rate down ReplyIf you want to know which DNS you should use for yourself, head over here and grab Steve Gibson's DNS benchmark tool. There's hundreds of 3rd party DNS servers out there besides OpenDNS and Google. (Windows only app)
http://www.grc.com/dns/benchmark.htm
I can actually somewhat confirm this. When I use my ISP's DNS (RoadRunner) I get an Akamai server in Dallas (I live in South Texas) on the RoadRunner backbone. When I use Google DNS, I get an Akamai server in Marietta, Georgia on the Comcast backbone. OpenDNS also gives a Dallas server, but it is off the RoadRunner backbone, making it 'farther.' I used traceroute and nslookup to find this out. One could use these tools with their own connection to determine what is best.
December 20 2010 at 5:36 PM Report abuse Permalink rate up rate down ReplyYes, GeoDNS means that the Akamai server you connect to depends on the location of the DNS server you are using.
So using your ISP's DNS server will generally mean you connect to the Akamai server that they intend you to use. Using an alternate DNS provider generally means you will connect to the Akamai server local to that provider.
Sometimes this will make things better, sometimes it will make things worse. In my case (Time Warner Cable, SoCal) switching made my Apple TV streaming work again. I suspect the local Akamai server was being overloaded, or maybe the ISP's path to it was inadequate.
For other people, the public DNS service the switch to could be a long way away, resulting in you connecting to a very remote Akamai server. (Hint: try doing a traceroute to your DNS server's IP address).
IMO, Apple would be better off dealing with these issues themselves, by connecting to a few different servers in the area and dynamically adjusting based on RTT times/throughput heuristics. Local servers can be detected using GeoIP techniques instead of DNS, and Apple's HTTP live streaming format splits the stream into chunks so it would be relatively easy to switch mid-stream.
Except DNS has nothing to do with routing. Or, perhaps I should say "shouldn't." If Akamai is somehow using DNS lookups to determine load balancing, then they need to hire a new IT staff.
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