In desktop support activity, there are three levels. DL1, DL2 and DL3. After DL3, the next stage will be the team leader. This system will vary from Organisation to Organisation. My son works in TCS as L3 engineer. As far as I know, the qualification required for all these levels is same only. But based on the years of experience you will be getting promoted. My son was working in HCL company as L1 support. After working for 2 1/2 years he shifted to TCS as L2. Now in the same company, he got promoted as L3. To switch our to L3 you may have to put up required experience in the same Organisation where you are presently working. Another way is to apply for another company where your profile matches with your experience and qualification for the DL3 position. Anyhow updating and upgrading our skills always with certification courses and other diplomas is a positive addition to our profile and will give better chances for climbing the ladder in our career.