DNS errors for the PlayStation 3 are typically caused by a bad connection to an Internet service provider's domain name system servers, which is a symptom of outdated hardware or software running the ISP's DNS servers. This error can be circumvented by pointing the PS3 connection settings to a different DNS server in the Internet settings control panel.
Domain name systems servers act as routing systems for Internet connections, pointing computers or consoles to the IP address of the end destination. The practice of entering dot com sites uses DNS servers, where the connection software resolves the website address into an IP address that can be viewed by a person over the Internet. When a DNS server is not functioning properly, it has trouble resolving these addresses, and the connection cannot be completed properly. Connecting via different DNS servers can fix this problem.
A PlayStation 3 is a video game console that uses wireless or direct connections to access the Internet, and it uses the same DNS services that a PC does. The PlayStation 3 console defaults to the main DNS server of the ISP providing the connection, which can be a problem if the ISP has an unreliable DNS service.