It's a different type of security. ST is very old school local telco work like administering policy, maintenance of network hardware/software & troubleshooting.

These jobs are now mostly outsourced to Indian and Pinoy in big MNCs and the ST brand itself also not good in the market, exp can only move around GLC and SME, most international MNC won't accept if stay too long.

For such low security jobs, better to opt for stat board which has better job security and pay/bonus stability.