Why the GPRS tweak will not work and why it is dangerous to change your DNS server addr.
A DNS server is basically used to convert a hostname/url like ?www.abhishta.net? to a corresponding I.P. address like ?192.168.1.1″. It will not improve loading times, download rates in any way.
But some users reported an increase in their browsing speeds. How did this happen? Let me explain it to you in brief:
A GSM system uses TDM or Time division Multiplexing, wherein each user transmits in predefined time slots. Since GPRS/EDGE is an overlay over GSM, it works in the same way. Initially, the network starts your connection by assigning you a single slot with the most conservative data rate. As it sees that your bandwidth requirement increases, it will try to increase your data rate by decreasing the coding rate (you still transmit in a single slot) if the channel conditions permit. However, if that is not enough, it will then try and assign you extra time slots to transmit, provided the network is not busy. Thus, your data rate increases gradually as you start your packet data session. So if you started your speed test with the network default settings and found your data rate to be say, 50kbps and then if you changed your DNS settings and re-ran the test, the network knowing that you have an active data connection, will allocate additional resources to you. That?s why you see an immediate increase in your speeds.
I would STRONGLY recommend people to keep the DNS server to the network default as a bad DNS server could lead to DNS spoofing.
Let us take the example of a bank, say for example, Bank of America. Its url is ?www.bankofamerica.com? and its actual IP address might be 129.2.24.23 (hypothetical IP address). And this is available in your DNS server. Now, someone comes along and says, change your DNS server to blah blah and you will get better speeds. Trusting him, you do it. In the new DNS server, www.bankofamerica.com is now mapped to IP address 129.24.56.20 which belongs to a hacker. The hacker runs a web server from that IP address and hosts a spoofed version of the bank of america website. And on that duplicate website, the moment you enter your username and password, it gets stored into the hacker?s database and your identity is compromised.
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