So with 3G services about to start from the private operators, users may have many doubts regarding the 3G services. Some of the Questions I here most often regarding 3G services are answered here:
Can I use 2G Sim for 3G services?
Yes. But, if you have a really old Sim card of only 16K (or even 32K), you may want to upgrade your Sim for better service experience.
What is difference between Sim and USIM?
What SIM is to GSM (2G), USIM is to UMTS (3G). So basically, USIM is the Sim card for a 3G network. But as said previously, you can use your 2G Sim card and get 3G services as well.
What are the advantages of USIM?
There are several advantages. The one that most can observe is the available of higher memory. For example, the USIM that BSNL provides for its 3G services has 128K memory. Most 2G Sim cards will have a memory of 32K, with some latest 2G Sim having 64K memory.
Apart from just Memory expansion, there are several security features available in USIM, that are absent in SIM card.
What charges are levied for upgradation from 2G Sim to USIM?
This will be known only when the carriers actually start 3G services. As far as BSNL USIM is concerned, the cost of USIM alone is Rs.300.
If you want to continue with the same number as before (2G) for the 3G services, you should migrate to 3G USIM (this depends on technical feasibility). At present, BSNL charges Rs.110 for migrating from SIM to USIM retaining the same number in case or Postpaid and Rs.151 in case of Prepaid.
If you have any other Questions, please ask them in the comments section below.