Direct Routing vs Operator Connect in Southeast Asia: an honest comparison

It's 3:00 PM on a Tuesday. I'm sitting in a kopitiam somewhere between Petaling Jaya and Singapore's CBD, sipping a kopi-O kosong, listening to a very stressed IT Director across the table. He's pulling his hair out.

"My boss went to a tech seminar," he says, eyes twitching. "Now he wants to move all our 3,000 staff across five ASEAN countries to Teams Voice by next month. Should we use Direct Routing or Operator Connect?"

I almost choked on my coffee.

In the pristine, air-conditioned halls of vendor presentations, the choice between Direct Routing (DR) and Operator Connect (OC) sounds like a polite menu option. Would sir prefer the steak or the fish? But out here in the trenches of Southeast Asian telecommunications — where carrier maturity varies more wildly than the spice levels of local sambal — it's not a preference. It's a survival strategy.

Having spent a decade configuring Ribbon SBC 5400 Cores and AudioCodes gateways to talk to every conceivable flavor of legacy PABX across this region, I can tell you the truth: what works perfectly in a Marina Bay high-rise will absolutely crash and burn in a Manila manufacturing plant if you don't know what you are doing.

So, let's cut through the marketing fluff. Here is the honest, battle-scarred comparison of Direct Routing vs Operator Connect, and where each actually fits in our beautiful, chaotic region.

The TL;DR: What exactly are we arguing about?

Before we dive into the geographical madness, let's simplify the tech. Microsoft Teams is the ultimate cloud PBX. But it needs a bridge to dial out to the real world (the Public Switched Telephone Network, or PSTN). You have two main ways to build that bridge.

Operator Connect (OC) is like taking a Grab (or Uber, for the mat sallehs). You open the Teams Admin Center, pick an approved local telco partner from a dropdown list, provide the permissions your OC vendor requires, assign phone numbers to your users, and you are done. The telco handles the connection to Microsoft. They own the Session Border Controller (SBC) in their data center. It is beautiful, simple, and requires almost zero telecom knowledge.

Direct Routing (DR) is purchasing a Hilux and modifying it yourself the way you deem fit. You buy your own SIP trunks from any telco. You deploy your own SBC — whether it's a physical Ribbon Edge 8100 in your server room, or a virtual AudioCodes Mediant in Azure. You control the routing rules, the dial plans, and the failovers. It's complex, it requires expertise, but it gives you absolute control over everything.

So, do you grab the Grab or drive the Hilux? Let's look at the map.

Singapore: The Atas Cloud Utopia

Let's start with the easiest one. Singapore is the undisputed telecom maturity capital of the region. The fiber is everywhere, the latency is practically non-existent, and the major players (Singtel, StarHub, and others) are heavily integrated into Microsoft's Operator Connect ecosystem. You can port fixed line numbers.

If you are a corporate office in Singapore with 500 staff who only use laptops, wireless headsets, and mobile phones, Operator Connect is a no-brainer. You can provision numbers while eating your chicken rice. It's seamless, fully managed, and highly reliable.

When to still use Direct Routing in SG? You use DR if you are kiasu (fearful of losing out) about your advanced integrations. If you have a massive customer service contact center — Genesys or NICE — that needs to share the SIP trunks with Teams, or if you want to implement AI voice bots that intercept calls before they hit the user, OC's "closed box" won't let you do it easily. You need your own SBC to split and control that traffic.

Malaysia: The Boleh Hybrid Battleground

Ah, Malaysia. Truly Asia, and truly a hybrid environment. Telcos like TM, Maxis and TIME are massive, but the infrastructure maturity can shift dramatically depending on whether your office is in downtown KLCC or a sprawling manufacturing plant in Shah Alam.

Operator Connect is gaining serious traction here for white-collar offices. But Malaysia is still heavily industrialized.

The Direct Routing reality: try telling a factory manager in Penang that they can't connect their 40 analog overhead paging horns, their legacy DECT phones, or the guardhouse intercom because Operator Connect doesn't natively speak analog. In Malaysia, we deploy Direct Routing nine times out of ten for mid-to-large enterprises. Why? Because you absolutely need an on-premise SBC — like an AudioCodes Mediant or a Ribbon EdgeMarc — to act as the middleman for all those physical, analog devices that refuse to die.

You also want DR because you might want to negotiate SIP trunk rates between two different telcos to get the best price, which DR allows you to do without being locked into one vendor's app store. Full control of call routing, failover policies and perhaps even compliance recording via SBC SIPREC — all of these absolutely mean Direct Routing in some form.

Indonesia & The Philippines: The Wild West (Bring Your Own Hilux)

If you try to deploy a pure cloud Operator Connect model for a highly distributed enterprise in Indonesia or the Philippines, you are going to have a very bad time.

Here, carrier maturity is fragmented. You are dealing with thousands of islands, complex local regulations — like strict local PSTN breakout laws where voice traffic must terminate through a local domestic carrier — and let's be honest, internet connections that sometimes drop when a heavy rainstorm hits Jakarta or Manila.

Direct Routing is mandatory here. You don't just want Direct Routing; you want Direct Routing with a Survivable Branch Appliance (SBA). An SBA is a feature built into enterprise SBCs that keeps your local phones working even if the internet connection to the Microsoft 365 cloud completely dies.

If a backhoe cuts the fiber line outside your Manila office, an SBA ensures that your staff can still pick up their Teams IP phones and make emergency PSTN calls out through a local, physical backup line. Operator Connect simply cannot save you when the WAN goes dark. In these countries, you drive the Hilux, and you bring a spare tire.

Vietnam & Thailand: The "Trust, But Verify" Zones

Vietnam and Thailand are modernizing at lightning speed. You'll find pockets of incredible 5G and fiber infrastructure, but the B2B telco offerings for SIP and cloud voice are still a mixed bag. Not every local carrier is fully certified for Operator Connect yet, and those that are might still be figuring out their own internal support SLAs.

In these markets, Direct Routing gives you the ultimate superpower: carrier agility.

If you lock yourself into an Operator Connect contract with a local telco and discover their voice quality is dropping packets like hot potatoes, migrating away is a massive headache. The network points only to Teams, eliminating flexibility. With Direct Routing, your Ribbon SBC 5400 Core sits in the middle. If Telco A starts giving you terrible service, you just plug in a SIP trunk from Telco B, update the routing table in the SBC, and migrate your traffic over a weekend without the end-users even noticing. You own the routing, so you own your destiny.

So, How Do You Choose?

After more than 150 deployments, the decision matrix we use with our clients usually boils down to this.

Go with Operator Connect if:

• You have a lean IT team that breaks into a cold sweat when they hear the acronym "SIP."
• Your users are purely "knowledge workers" sitting in modern offices in high-maturity markets like Singapore.
• You have exactly zero analog devices, paging systems, or fax machines left on your premises.
• You don't need complex contact center or AI voice integrations.
• You can migrate with a big-bang approach.

Go with Direct Routing if:

• You are a large enterprise, necessitating a smooth migration over a few phases.
• You are migrating offices, factories, hospitals, or hotels that still rely heavily on analog endpoints and physical infrastructure.
• You operate in Indonesia, the Philippines, or anywhere else where internet reliability demands local survivability (SBA).
• You want the negotiating power to mix and match multiple telcos across different countries while funneling them all into a single Microsoft Teams tenant.
• You have an IT team — or a good system integrator — who actually enjoys tinkering with the deep, dark magic of regular expressions, call routing policies, and SBC failover architectures.

The Summary

There is no "one size fits all" when it comes to voice migration in Southeast Asia. Our region is too beautifully diverse for a single cookie-cutter architecture.

Operator Connect is a phenomenal leap forward in simplifying cloud voice. It is the sleek, modern future we were all promised, and for standardized corporate offices, it is an absolute dream to deploy and manage.

But Direct Routing remains the heavy-duty toolkit that holds the region's complex, messy, and highly customized telecommunications infrastructure together. Whether you are navigating the strict regulatory environments of Jakarta, connecting legacy factory horns in Penang, or routing advanced contact center traffic in Singapore, Direct Routing — powered by rock-solid SBCs — gives you the unyielding control required to make it work.

The secret isn't picking the newest technology just because it looks good in a PowerPoint presentation. The secret is knowing exactly what kind of road you are driving on before you choose the vehicle. So, do your discovery, map your endpoints, understand your local telco's true maturity, and when in doubt, ask an expert over a good cup of coffee.