Why network architecture matters for UK financial firms
Updated: 7 days ago
A slow or unreliable network can disrupt trading platforms, client services, cloud applications and the systems firms rely on every day. For UK financial organisations, network architecture now sits at the centre of operational resilience. It is no longer a background IT decision.
This article explores why resilient network design matters, how it connects to regulatory expectations, and what a reliable architecture looks like in practice.
The risk is already visible
Network resilience directly affects a firm's ability to deliver critical services.
In the Bank of England's 2026 H1 Systemic Risk Survey, cyberattack was cited by 82% of respondents as one of their top five risks to the UK financial system. Risks relating to artificial intelligence were cited by 32%, and infrastructure disruption by 16%. The survey drew responses from 57 firms, including banks, insurers, asset managers and hedge funds.
The Bank of England is clear that firms need robust plans to keep important services running through cyberattacks, IT outages and third-party failures. A network that cannot absorb disruption puts those plans at risk.
What regulators expect
UK operational resilience rules from the PRA and FCA require firms to identify their important business services, set impact tolerances for each, and demonstrate they can remain within those tolerances during severe but plausible disruption. The deadline for full compliance was 31 March 2025.
Network architecture underpins every one of these requirements. If a single connection, data centre or provider failure could push a service beyond its tolerance, the architecture needs to change.
Two further frameworks raise the stakes:
DORA has applied since January 2025 to financial entities operating in the EU, with detailed requirements for ICT risk management and resilience testing.
The UK critical third parties regime brings designated technology providers, including major cloud platforms, under direct regulatory oversight. Firms remain responsible for managing their own dependency on those providers.
Build around important business services
A resilient network starts with mapping which systems support each important business service. These include trading platforms, payment processing, client portals, analytics and remote access.
Each has different requirements. Trading systems may need low-latency, deterministic connectivity. Client portals need high availability. Back-office analytics may tolerate brief delays but hold sensitive data. Designing around these differences prevents over-engineering in some areas and dangerous gaps in others.
Make cloud connectivity part of the design
Most financial firms now run a mix of on-premises, private cloud and public cloud environments. The Bank of England notes that cloud services can improve scalability and resilience while introducing concentration and third-party risk.
Priority | Purpose |
Secure, identity-based access | Protect systems and sensitive data |
Resilient cloud connectivity | Avoid single points of failure between sites and providers |
Performance monitoring | Detect degradation before it affects services |
Backup and recovery | Maintain continuity during outages |
Third-party risk management | Understand and plan for provider dependencies |
Security starts with architecture
Network segmentation separates critical workloads from general user traffic, limiting how far an attacker or fault can spread. Zero trust principles take this further by verifying every user and device, regardless of location.
Continuous monitoring gives IT teams early visibility of unusual traffic, performance issues and potential threats.
Design for failure, not just performance
Resilience should be designed in, not added after an incident. A useful test is to ask what happens if each critical component fails.
Consider a firm whose trading platform relies on a single internet circuit into one data centre. A fibre cut takes the platform offline, and the firm breaches its impact tolerance within the hour. With dual-carrier connectivity, diverse routing and automated failover, the same event goes largely unnoticed.
A resilient architecture typically includes:
Dual-carrier or diverse-path connectivity
SD-WAN for intelligent traffic routing and failover
Redundant hardware at critical sites
Resilient links to cloud providers
Tested recovery procedures aligned to impact tolerances
Continuous monitoring and alerting
Support hybrid teams and third-party access
Remote staff, contractors and third-party vendors all need secure access to firm systems. Identity-based controls, least-privilege access and secure remote connectivity keep that access consistent without widening the attack surface.
As firms adopt new cloud applications and AI tools, the network must adapt without introducing new weak points. Ongoing management keeps performance, security and change control on track.
Build a network that's ready for what's next
A resilient network supports the performance, security and continuity that UK financial firms and their regulators depend on. With the right architecture and ongoing management, it becomes a foundation for reliable operations and a clear part of your resilience evidence.
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