GSM Gateway Modification

Job ID: 39567128

Budget: ₹1,500 – ₹12,500 INR

I need help modifying a Skyline 8-port GSM gateway to enable calling to China. Currently, calls to China return a 403 response code.

Requirements:
- Modify firmware or settings to allow these calls
- Hardware modification is acceptable
- Current firmware version is uncertain
- I can provide detailed model and specs

Ideal skills and experience:
- Experience with GSM gateway configuration and modification
- Familiarity with handling 403 response codes
- Knowledge of firmware and hardware modification

Please provide a solution to enable calling to China.