Founder and technical leadership
Founder and Technical Director of THIRTY NINE DEGREES LTD
Matthew Southgate is the founder and technical director of Thirty Nine Degrees Ltd, with more than 20 years of experience across ISP networks, business technology, Microsoft 365, VoIP, resilient infrastructure and cyber security.
Matthew provides technical leadership across UKDDI, 39D, 39Security, 39T and 39 Networks within the wider 39 Group.
UKDDI focuses on business telephone numbers, SIP services and voice delivery. The wider group connects those services with managed IT, Microsoft 365, cyber security, business connectivity, managed Wi-Fi and ISP network expertise.
Matthew's background spans ISP operations, routing policy, BGP, IPv6, multi-carrier connectivity, high availability, DDoS resilience and business-critical network infrastructure.
His work combines technical architecture with day-to-day operational responsibility across Microsoft 365, devices, servers, cloud systems, backups, security controls and business continuity.
Experience includes business phone systems, SIP trunks, 3CX-compatible routing, hosted voice, number provisioning and resilient communications design.
Matthew leads practical security work covering identity, endpoint protection, managed networks, incident readiness, recovery planning and resilient infrastructure.
His background includes ISP operations, BGP, IPv6, Microsoft 365, business phone systems, SIP and VoIP, resilient infrastructure, cyber security and business continuity planning at Visa during the Millennium Bug.
Matthew's early career included business-continuity planning for Visa, the card-payment organisation, during preparations for the Year 2000 transition. That work helped shape a practical focus on resilience, documented recovery and making sure critical services continue when technology changes or fails.
Matthew's published profile connects his work with business phone systems, SIP, VoIP and resilient infrastructure. UKDDI applies that experience to number inventory, service configuration, SIP packages, recurring payments and VAT invoicing.
Qualifications and career claims are linked to certificates, published profiles, event pages, articles or other external sources wherever available.
Matthew contributes to technical briefings, cyber-security training and business events intended to make complex risks and systems easier to understand.
Published guidance focuses on practical decisions for established small businesses, including cyber risk, Microsoft 365, managed detection and operational resilience.
Choose a UK number online or contact UKDDI for SIP, 3CX, hosted voice, routing and number-porting requirements.