A quick ping testing indeed explains everything. As for my analysis, i took www.yahoo.com as example. This is done before get "disconnected".
ping www.yahoo.com
Pinging www.yahoo-ht3.akadns.net [87.248.113.14] with 32 bytes of data:
From the pinging output, we can derives that domain name is actually translated to the following IP via DNS server.
www.yahoo.com=87.248.113.14
In order to determine the DNS server is the real culprit, i did a separate ping on the domain name and the translated IP when the error page returned.
ping www.yahoo.com - Negative result
ping 87.248.113.14 - Positive result
As a result, it clearly shows the internet connection is up but the DNS server failed to translate the domain name to the corresponding IP. In other words, you can still access to yahoo web site if you hit the site IP directly. Eg, http://87.248.113.14
According to Maxis, all the broadband user DNS settings should be set as automatically. The problem is sometimes the DNS settings might lost in the space and hence "disconnecting" the user. In fact, this also affects Streamyx subscriber frequently. Thank to Google, i managed to find a Maxis DNS IP that revitalize my browser. Apparently this DNS settings is meant for the GPRS service, but as long as it works:D
These are the one and only Maxis DNS server found in the net:
Primary DNS: 202.75.129.101
Alternate DNS: 202.75.129.102
Alternatively, should you run out of idea what DNS IP to use, you can always opt for the public DNS server. Check it out at http://www.opendns.com/
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Hope this could help some of the desperate Maxis broadband subcriber out there;)