Using iPhone Safari over WiFi is DNS sensitive
Since I got my iPhone I’ve been really enjoying its slick user interface and ease of web browsing, but I started to notice that Safari was for some web sites loading pages very slowly. In fact for some web sites Safari would not load pages at all.
I found that if I switched WiFi off I could load these stubborn pages no problem over GPRS/EDGE. I thought I had found the iPhone Achilles Heel; WiFi browsing was just not all that it was cracked up to be. I could browse these web sites just fine using Firefox or IE on my Sony Vaio Laptop over the same WiFi connection. It had to be the iPhone that was at fault.
Resetting the Safari cache, cookies and history made no difference. I tried turning off Javascript too, to no avail.
Now my WiFi network router is an old Buffalo unit I’ve had years. I wondered if it was somehow not compatible with the iPhone, but it supports 802.11g so why should that be the case? Most odd.
I started going through the configuration for the WiFi router one setting at a time and considering how it might affect the iPhone differently to my Laptop. Nothing jumped out at me, until I got to the network settings.
No DNS information!
My network looks like this: Broadband Router –> CISCO Firewall –> WiFi Router –> PCs/Laptops/Consoles etc (either using WiFi or hard wired into the WiFi router).
Once I had filled in the IP address of the Broadband Router into the WiFi Router’s configuration, it resolved my problem. Safari on the iPhone was browsing any web site I liked at full speed.
I’m curious to know why none of our WiFi laptops or Nitendo Wii etc have had a problem with this, but I guess the iPhone is just very sensitive to DNS information.
So If you are experiencing slow page load times in Safari over WiFi on your iPhone, double-check ALL the DNS settings throughout your network.
via http://www.timskipper.net/blog/internet/using-iphone-safari-over-wifi-is-dns-sensitive/