AWS re:Invent 2025 - LSEG: Modernizing critical financial systems with multicloud and hybrid cloud

Modernizing Critical Financial Systems with Multicloud and Hybrid Cloud

Overview of LSEG

• London Stock Exchange Group (LSEG) is a global provider of market data and financial infrastructure, operating major trading platforms and offering a range of financial services.
• LSEG has a significant multicloud presence, with over 1,300 AWS accounts in addition to a presence on Azure and GCP, as well as a sizable on-premises footprint.

Challenges of Multicloud

• Regulated industries often have requirements around exit strategy, concentration risk, and diversity, which can drive a multicloud approach.
• Without clear direction, teams can build unique infrastructure, logging, monitoring, and other components across different cloud providers, introducing complexity.
• Operationalizing a well-secured, governed, and regulated cloud platform across multiple cloud service providers (CSPs) is challenging.
• Skill gaps, with most people being specialized in a single cloud provider, can hinder effective multicloud management.

LSEG's Multicloud Framework

1. Cloud Capability Framework: A common foundation of capabilities, standards, and principles for things like IAM, networking, and policy, stored in version-controlled Git repositories.
2. Core Cloud Platforms: LSEG has landing zones in AWS, Azure, and GCP, providing standard APIs for core platform operations.
3. Cross-CSP Capabilities: LSEG has standardized on common capabilities across cloud providers, such as policy engines, golden images, security tooling, and AI/ML tooling.
4. Native vs. Agnostic Services: LSEG prefers to use native cloud services whenever possible, only going for cross-platform solutions when there are clear regulatory, compliance, or operational reasons to do so.
5. Unified Orchestration and Management: LSEG has standardized on Terraform for infrastructure as code, building verified modules that comply with their security and policy frameworks.
6. Cloud Product Framework: LSEG provides a set of standardized, opinionated modules and services to their developers, abstracting the complexity of the underlying cloud platforms.

Benefits of LSEG's Multicloud Approach

• Increased developer productivity, with applications being deployed 80% faster in some cases.
• Improved security and compliance posture through a standardized framework.
• Enhanced collaboration and reuse among the platform engineering team.
• Cost savings in terms of resource, license, and operational costs.

FX Price Stream Modernization

• FX Price Stream is a global dealer-to-client streaming quote service that links liquidity providers with taker clients.
• Challenges included the need for modernization, low-latency performance, and high infrastructure costs.
• LSEG leveraged AWS Outposts to deploy the FX Price Stream application, achieving:
  • 2x improvement in latency, with 49th percentile latency of 1ms vs. 2ms on-premises.
  • 6x improvement in median latency, from 1.1ms to 181 microseconds.
  • 3.3x higher peak throughput, reaching 165,000 messages per second.
  • 2x faster sustained performance during peak load periods.

Resilient Clearing House on Hybrid Cloud

• The London Clearing House (LCH) is a critical national infrastructure organization that acts as a central counterparty to clear and settle financial transactions.
• Regulatory requirements mandated the ability to operate independently of the cloud service provider for up to 5 days in the event of a total outage.
• LSEG's solution leverages a hybrid cloud approach:
  • Primary region: Amazon EKS, Oracle RDS, S3, and FSx for NetApp ONTAP.
  • Secondary region: Data replication for disaster recovery.
  • Tertiary solution on AWS Outposts: EKS, Oracle EC2, and NetApp storage, providing the ability to operate independently for up to 5 days.
• LSEG has successfully tested the 5-day disconnect scenario, proving the resilience of the critical national infrastructure workloads.

Key Takeaways

• LSEG has adopted a structured approach to multicloud, balancing cloud-native and cloud-agnostic services.
• AWS Outposts can be leveraged for low-latency and high-resilience requirements, such as in the FX Price Stream and LCH use cases.
• LSEG's multicloud framework and product-centric approach have delivered benefits in terms of developer productivity, security, collaboration, and cost savings.
• Regulated industries can leverage hybrid cloud solutions, like LSEG's LCH architecture, to meet stringent resilience and independence requirements.