Author
Serhii Omelchenko
Global AEO/SEO Manager
Serhii is Global AEO/SEO Manager at Telnyx, based in Amsterdam, he is focused on making communications infrastructure findable and credible across both traditional search and AI-driven discovery. He previously led SEO and GEO strategy for some of the world’s most recognized consumer brands.
- 10
- Articles
- 2018
- Joined
Latest articles
Everything Serhii has published, most recent first.
VoiceWhat is call control? Direct, programmable control over every call
What is call control? Learn how call control works in a switch, a cloud API and a contact center, and how to transfer calls and stream media with Telnyx.
SIP TrunkingSIP response codes: a quick reference to every SIP code and error
SIP response codes, SIP codes and SIP error codes explained in two minutes: the full 1xx to 6xx list, what each code means, and which ones to retry or fix.
MessagingSMS vs MMS Explained for Developers: Limits, Cost and One API
SMS vs MMS compared for developers: character limits, media types, cost, when to send each and how to send both with one Telnyx API.
WhatsApp Business APIWhatsApp Business Messaging for Retail: Setup and Pricing
WhatsApp Business messaging for retail: order updates, promotions and support from one Telnyx number, from $0.004 a message. Setup steps and a sample API call.
WhatsApp Business APIWhatsApp Business for Hospitality: Guest Messaging, Costs and Setup
WhatsApp Business hospitality guide: how hotels, airlines and venues message guests across the stay, what it costs, and how to run it on one Telnyx number.
WhatsApp Business APIWhatsApp Business API Cost in 2026 After October 1
WhatsApp Business API cost in 2026: Meta's per-message rates after October 1, the 1,000 free service messages, BSP markup and a worked Telnyx example.
IoTIoT Devices: Definition, Examples, and How to Connect Them
Learn what IoT devices are, see examples by category, and compare the connectivity each device needs, with cellular data from $0.01 per MB.
WirelessHow to launch a white label eSIM reseller business
Compare ways to launch a white label eSIM reseller brand, what each costs to build and run, and how Telnyx eSIM puts your name on the network.
MessagingWhat is an SMS gateway and how does it work?
An SMS gateway routes text messages between applications and mobile networks. Learn how SMS gateways work, compare top providers, and integrate with the Telnyx SMS API.
MessagingRCS Business Messaging Pricing How It Works and What to Expect
RCS business messaging pricing depends on message type, destination, volume, and carrier. Learn how pricing works and what to ask providers before you commit.
