Hi,
L1 , L2, L3, L4 suppor is the Level of Issues or tickets you will receive during the Production support
They have different Severities and Priorities based on the Level of issue ( ticket)
Again the Priority and severity depends on the SLA of the Client
Each Client will have its own intrepretation for this
In some clients
L1 will be the Very High priority ticket and needs to be solved with in 4 hours
L2 will be High priority tickets and need to be resolved within 8 hours
L3 will be the Medium priority ticket and needs to be resolved within 24 Hours
L4 will be the Low priority ticket and needs to be resolved within 48 Hours
And the priority and the time period will depends on the client.
Please revert back if you need more details
regards,
santosh