TM MLS (Telekom Malaysia Multi Line SIP) is Telekom Malaysia's SIP trunking service — it carries multiple concurrent phone lines over an internet connection instead of traditional copper or PRI/E1 circuits. If you've been asked to move off an old PRI line, MLS is usually what TM offers as the replacement. Here's what it is and what you need to use it.
How TM MLS works
Instead of physical voice circuits, MLS delivers your lines as SIP channels over a data connection — it rides the same infrastructure as Unifi, so new sites don't need separate voice cabling. You buy a number of concurrent channels (how many calls can happen at once) plus your phone numbers.
MLS is the lines, not the phone system
This is the key point: MLS provides the trunk (the connection to the outside world). You still need a phone system — a PBX — behind it to route, answer, record and manage calls. That PBX can be on-premise or, increasingly, a cloud PBX.
TM MLS vs PRI
| Legacy PRI/E1 | TM MLS | |
|---|---|---|
| Delivery | Dedicated voice circuit | SIP over internet (Unifi infra) |
| New-site cabling | Required | Not needed |
| Scaling channels | Slow, hardware-bound | Easier |
| Future-proofing | Being retired | Current SIP standard |
What you need to use it
A SIP-capable phone system. Modern IP and cloud PBXs support SIP natively; a legacy TDM PBX can connect through a SIP gateway. Many businesses use the switch to MLS as the moment to move the whole phone system to the cloud — see our guide on moving from TM MLS to cloud.