3rd Line IT Engineer · London
Hey, I’m Sithin.
I secure, migrate and run the systems modern teams depend on: identity, endpoints, cloud and collaboration. Here I write up what actually works.
10+
years across infrastructure, modern workplace and IT audit
1,000+
users and 100+ domains moved from Google Workspace to Microsoft 365
~360
users moved to Netskope SSE with no disruptive cutover
98%
patch compliance across 1,000+ devices with ConfigMgr
Who I am
From the data centre floor to zero trust
I’m Sithin Sony, a systems engineer based in London. My career started in 2012 supporting servers, data centres and remote users at Cisco in Bangalore, and has since taken me through Doha, Kerala and London.
Along the way the job shifted from racking hardware to running identity, endpoints, SaaS and cloud for whole organisations, and to auditing those controls against ISO 27001, SOC, NIST and PCI-DSS. Today I’m a 3rd Line IT Engineer at proSapient, where I look after security, identity, cloud and the AI platforms the business runs on.
I started this blog to write up the things I wish I’d found when I needed them: real migrations, real configurations, and the trade-offs behind them.
What I work on
Six areas I spend my days in, and write about here.
Security & zero trust
Netskope SSE (SWG and CASB), Conditional Access, Purview DLP and zero trust policy built on identity, least privilege and continuous monitoring.
Identity & access
Microsoft Entra ID, SSO and SCIM federation across Google Workspace and Slack, privileged access and break-glass design.
Endpoints & devices
Intune MDM, Autopilot and Apple Business Manager zero-touch enrolment, plus patching at scale with ConfigMgr.
Microsoft 365 & Workspace
Exchange Online, Teams, SharePoint and Google Workspace administration, tenant migrations, and SPF, DKIM and DMARC done properly.
Cloud & infrastructure
GCP org hardening with VPC Service Controls, VMware vSphere, Meraki and UniFi networks, Datadog observability, and PowerShell and Bash automation.
AI platforms
Bringing Gemini Enterprise and Vertex AI into the business with federated identity, custom IAM controls and a clear cost model.
Selected work
Recent projects I’ve led
Cisco Secure Access to Netskope SSE
Delivered single-handedly for ~360 users across multiple sites with no disruptive cutover, including inline blocking of unapproved AI tools.
Microsoft 365 security uplift
Turned a 33-finding assessment into 37 tasks across Conditional Access, privileged access, Entra, Purview and Intune to support client due diligence.
Google Cloud organisation hardening
VPC Service Controls around GCS and Vertex AI for partner data, org policies blocking out-of-org projects, and audit logs streamed to Wiz.
AI platform strategy
Built a three-year cost model comparing Gemini, Claude and a hybrid, then deployed Gemini Enterprise with Entra federation and custom IAM.
Google Workspace to Microsoft 365
As Global Administrator, moved 1,000+ users and 100+ domains with a 99.9% data transfer success rate across 1,200+ mailboxes.
Zero-touch onboarding
Intune with Autopilot and Apple Business Manager cut onboarding time by 50% across Windows, macOS, iOS and Android.
The journey
Four countries, six roles
Mar 2025 – Present · London
3rd Line IT Engineer, proSapient
Security, identity, GCP and AI platforms, plus SaaS consolidation, email deliverability and Datadog observability for L3 operations.
Apr 2022 – Oct 2024 · London
System Engineer, CentralNic PLC
IT controls testing and ISMS in Vanta, the Google Workspace to Microsoft 365 migration, Purview DLP, Intune zero-touch and ConfigMgr patching.
Sep 2020 – Dec 2021 · London
IT Specialist, BoxMedia
Google Workspace and Microsoft 365, UniFi and Meraki networks, meeting rooms, and ISO 27001 asset audits for 500+ devices.
Jun 2017 – Jun 2020 · Kozhikode, India
Technical Specialist, Austeron Mediatech
VMware vSphere and vSAN for 500+ virtual machines, and Microsoft 365 for 300+ users.
Apr 2017 – Jun 2017 · Doha, Qatar
Systems & Network Administrator, Skyway Group
SCCM deployment for 300+ workstations and a 600+ user move to Office 365.
Nov 2012 – Mar 2017 · Bangalore, India
Systems & Network Administrator, Cisco
Servers, network systems and the local data centre, with remote support for 200+ users.
Certifications
- CISA
- ISO 27001 Internal Auditor
- CompTIA Security+
- ITIL
- M365: Intune Expert
- M365: Administrator Expert
- CCNA
Education
- Master’s degree, Network & Information Security, Kingston University (2020–2022)
- Bachelor of Computer Applications, Kristu Jayanti College, Bangalore (2009–2012)
The toolbox
Netskope SSE · Cisco Secure Access · Microsoft Entra ID · Intune · Autopilot · Apple Business Manager · Purview · Exchange Online · ConfigMgr · Google Workspace · Google Cloud · Vertex AI · Gemini Enterprise · Wiz · Vanta · Datadog · Slack Enterprise Grid · Cisco Meraki · UniFi · VMware vSphere · vSAN · AWS · PowerShell · Bash · ServiceNow · Jira · Confluence
Explore the blog
Pick a topic, or get in touch if something here helped or you’d like to compare notes.