The current major mobile internet deployment in India is EDGE with pockets of 3G deployed by couple of operators. EDGE gives a maximum speed of 384Kbps with per channel capacity being around 50Kbps max.
So a user on EDGE is atleast guaranteed a 64Kbps speed, which is fair enough for email and chat. EDGE is based on legacy GSM radio technology. On the other hand 3G has picked up the radio technology from CDMA. CDMA is superior in terms of data speeds when compared to GSM.
3G has WCDMA as radio technology for data access. Further upgrades to 3G are HSPA and HSPA+.With so many technologies users experience different speeds at different times in different networks.
The user experience depends on various factors and it is not a good idea to judge Bangalore network based on what is received in a Delhi network.
When a user is connected to the network he will be assigned one or more channels based on the network conditions. More the channels more is the speed. With HSPA networks the per channel data rate has increased tremendously. While in the nights if the network is free, users may experience speed upto 7 to 21 Mbps based on HSPA or HSPA+.
Important thing to note here is downlink and uplink speeds are different. This is a technology limitation. Usually one is expected to download more data then upload it. So the technology is designed in such a way that users get more downlink capacity. With such a high speeds every body can surf internet pretty well. But the story doesn’t end here.
Web browsing doesn’t need 7 Mbps of bandwidth. May be video stream will. Here comes the operator control. First a pipe will be created for the user for accessing internet. Next based on the what user is accessing a secondary pipe may be created.
The secondary pipe can be made fatter or thinner based on what user pays. For e.g. a corporate user wants to get all his emails on mobile. So apart from usual pipe a separate pipe will be created for this user, in which all his emails flow, thus increasing the quality of email experience for the user.
There could also be cases where a video stream may be given lower priority in the network so that you tube videos may not consume the whole bandwidth there are several intelligent ways to deal with this.The bottom line is users cannot expect same speed all the time in all the networks.