Route quality, numbering regulation, messaging deliverability and enterprise WAN design - written by the engineers and carrier-relations people who run the interconnects they describe.
Both replace the phone system, both live in the cloud, and both vendors will tell you they do what the other one does. The right choice depends on who answers the calls, what happens when nobody can, and what the business needs to know about it afterwards.
A SIP trunk is reachable from the internet, and somebody is scanning it right now. The controls that keep it safe are not exotic - TLS and SRTP, IP authentication, sensible limits and a carrier that watches for fraud - but they only work if every one of them is switched on.
A one-time passcode is only useful if it arrives before the user gives up. Here are the latency and conversion numbers we consider healthy, the route decisions that move them, and how to keep artificially inflated traffic from quietly eating the budget.
Porting a few hundred numbers across five countries is five different projects wearing one name. This is how we run them - the letters of authorisation, the realistic timelines per market, and the pitfalls that turn a two-week port into a two-month one.
ISDN switch-off dates are now fixed in most major markets. Moving from PRI to SIP is not just a like-for-like swap - it changes how you buy capacity, how you fail over, and what a phone number is attached to.
A local number in a country you have no office in is a regulatory question before it is a technical one. What each major region asks for, how long it takes, and how to avoid having numbers reclaimed after activation.
An OTP that arrives in eight seconds is a product feature. One that arrives in four minutes, or not at all, is a support ticket. Where deliverability is actually decided, and what a delivery receipt does and does not tell you.
Your calls can be perfectly legitimate and still show up as "Scam Likely". How call authentication works, why analytics engines label numbers, and the operational habits that keep an enterprise's outbound numbers clean.
The MPLS-versus-SD-WAN debate is mostly over, and the answer was "both". What each transport is good at, where SD-WAN overlays fall short on their own, and how to size a hybrid WAN across markets with very different last-mile realities.
Voice fraud costs the industry tens of billions a year, and most of it follows three well-understood patterns. What each one looks like on the wire, why it works, and the layered controls that catch it before it reaches your invoice.
Teams has become the phone system for a large share of enterprises, and there are three ways to give it a dial tone. How each works, what it costs to run, and which one fits a multi-country organisation with existing carrier relationships.