Client Overview

A rapidly growing financial services organization needed a secure, resilient, and centrally managed network architecture connecting multiple offices across several cities, its on-premises datacenter, and production workloads hosted on AWS.
A key requirement was seamless and secure integration with core banking services, delivered through a national MPLS backbone.

Business Challenge

The client faced several challenges in scaling their distributed operations:

• Offices in different cities had inconsistent connectivity, leading to latency and downtime.
  
• No unified WAN strategy to securely access core banking applications hosted on the bank’s MPLS network.
  
• Increasing reliance on AWS workloads required low-latency, private connectivity rather than internet-based VPN.
  
• Need for strong security posture: segmentation, encrypted tunnels, identity-based access, and centralized management.
  
• Required high availability for financial operations, branch transactions, reconciliation, and back-office systems. 

The objective was to design a single, unified enterprise network with secure hybrid cloud integration and guaranteed service availability across all branch locations.

Our Solution

1. Multi-City Office Network Architecture

We designed a standardized network architecture for all office locations, ensuring consistency, security, and fault tolerance.

1.1 Standardized Branch Network Blueprint

Each office was equipped with:

• Dual WAN routers for high availability
  
• Redundant firewalls (active/passive) with centralized policies
  
• Dual Internet links + MPLS link, depending on branch size
  
• SD-WAN overlay (optional) for application-aware routing
  
• Redundant switches (core/distribution/access)
  
• Segmented VLANs for:
  
  • User LAN
    
  • Guest network
    
  • IP telephony
    
  • Surveillance
    
  • Server/IT Ops
    
  • Payment/transaction systems (PCI-aligned) 

1.2 Unified WAN Connectivity Across Cities

To interconnect branches securely:

• Established an MPLS Layer-3 VPN backbone between all offices.
  
• MPLS provider delivered QoS-enabled circuits for:
  
  • Financial transactions
    
  • Core banking access
    
  • Real-time applications (VoIP, video) 
• ECMP routing enabled load-sharing over MPLS & internet-based IPsec tunnels (where applicable).
  
• BGP used as the dynamic routing protocol for predictable convergence. 

1.3 High Availability Across All Branches

• Redundant firewalls with state sync
  
• Multiple ISP uplinks with automated failover
  
• Hot standby router (HSRP/VRRP) for gateway redundancy
  
• Loop-free switching architecture using Rapid Spanning Tree or MLAG
  
• Automated monitoring for link health and latency 

2. Integration with Core Banking Services via MPLS Backbone

Because the client relied heavily on core banking systems:

• A dedicated MPLS VRF was provisioned by the bank’s telecom provider.
  
• Branch routers connected directly to this VRF for:
  
  • Transaction processing
    
  • Ledger synchronization
    
  • Payment gateway access
    
  • Authorization/verification services 
• BGP communities and route filters enforced strict traffic control.
  
• End-to-end segmentation ensured that only authorized subnets reached the banking network. 

Result:
Financial transactions across all branches became consistent, low-latency, and secure, supporting regulatory and audit requirements.

3. Hybrid Cloud Integration with AWS

3.1 Production Workloads on AWS

The client hosted critical production workloads on AWS, including:

• Core APIs and microservices
  
• Batch processing engines
  
• Customer-facing applications
  
• Analytics & reporting systems
  

These workloads required secure, private, and low-latency connectivity from all branches and the datacenter.

3.2 AWS Direct Connect Integration

We deployed a redundant AWS Direct Connect (DX) architecture:

• Two DX circuits to separate AWS PoPs
  
• Private VIF connecting to AWS VPC production environment
  
• DX gateway used for multi-VPC design
  
• BGP sessions between DX routers and AWS edge routers
  
• VPN failover for DX outage scenarios
  

Routing Architecture:

• MPLS → Datacenter Core → Direct Connect → AWS
  
• Optional SD-WAN tunnels for branch-to-AWS direct paths
  
• Segmented routing tables for production vs. non-production traffic 

Outcome:
Branches could securely access AWS workloads without relying on public internet, dramatically improving reliability and reducing latency.

4. Security Architecture & Zero-Trust Controls

A multi-layered security model was implemented:

• Firewall policies centrally managed using templates
  
• Zero-trust segmentation using:
  
  • VRFs
    
  • VLANs
    
  • Security zones
    
• IAM-based access for cloud workloads
  
• End-to-end encryptions for internet tunnels
  
• Intrusion detection & threat monitoring using SIEM
  
• Logging across branches consolidated in a central SOC 

5. Monitoring, Observability & Operations

A unified NOC view was created:

• Real-time link monitoring for MPLS, Direct Connect, and ISPs
  
• SNMP/NetFlow/Telemetry-based analytics
  
• Automated failover drills
  
• SLA dashboards for branch availability
  
• CloudWatch integration for AWS network paths 

Results & Business Outcomes

✔ Unified Enterprise Backbone Across All Cities

All branches now connect over a single secure MPLS cloud with consistent performance.

✔ Reliable Integration with Core Banking Systems

Financial transactions and payment services became faster and more predictable.

✔ Low-Latency, Secure Access to AWS Production Workloads

Direct Connect provided predictable bandwidth and private connectivity.

✔ High Availability Across All Branch Locations

Redundant routers, firewalls, and ISP links minimized downtime.

✔ Strong Compliance & Security Posture

Network segmentation and Zero-Trust design aligned with banking and financial regulations.

✔ Scalable Foundation for Growth

New branches and cloud workloads can be added without redesigning the network.

Conclusion

The end-to-end network architecture transformed the client’s distributed operations into a secure, resilient, hybrid enterprise network.
By integrating multi-city offices via MPLS, enabling private AWS connectivity with Direct Connect, and ensuring a high-security, high-availability design, the client is now equipped with a network backbone that supports their financial services reliably and at scale.

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Executive Summary – Multi-City Enterprise Network with MPLS Backbone & AWS Direct Connect

Overview

A growing financial services enterprise required a highly available, secure, and centrally managed network to support its offices across multiple cities, integrate with core banking systems over an MPLS backbone, and connect to production workloads hosted on AWS.
The new design needed to eliminate branch connectivity issues, standardize security controls, and deliver resilient access to mission-critical financial and cloud applications.

Business Challenges

• Inconsistent network performance across city offices
  
• No unified, secure connectivity to banking systems
  
• Latency issues with AWS-hosted production apps
  
• Lack of standardized branch network architecture
  
• Requirement for 99.99% uptime, redundancy, and regulatory compliance
  
• Need for centralized monitoring, visibility, and governance 

Solution Highlights

1. Multi-City Branch Network Architecture

• Standardized branch design with dual routers, dual firewalls, and redundant switches
  
• Multiple WAN paths (MPLS + dual ISP) for high availability
  
• Segmented VLANs for users, finance systems, guest Wi-Fi, surveillance, and IT operations
  
• Optional SD-WAN overlay for application-aware routing 

2. MPLS Backbone for Core Banking Integration

• Dedicated MPLS Layer-3 VPN provided secure access to banking applications
  
• BGP routing for consistent, low-latency transactions
  
• Segregated VRFs and strict route filtering for regulatory compliance
  
• Ensured reliable transaction processing, ledger sync, and payment operations 

3. Hybrid Cloud Connectivity with AWS Direct Connect

• Redundant AWS Direct Connect (DX) circuits for private, low-latency access
  
• DX Gateway for multi-VPC production environment
  
• BGP-based routing with VPN fallback for DR scenarios
  
• Secure, high-performance access from all branches to AWS production systems 

4. Security & Monitoring

• Zero-Trust segmentation using VLANs, VRFs, firewall zones
  
• Centralized firewall policy management
  
• End-to-end encrypted tunnels for internet paths
  
• Unified NOC view with real-time monitoring of MPLS, DX, ISP links, and AWS traffic 

Key Outcomes

✔ Unified, Reliable Enterprise Backbone

Seamless connectivity across all city offices with predictable performance.

✔ Secure, Compliant Access to Core Banking

MPLS VRF design ensured strong security, low latency, and regulatory alignment.

✔ High-Performance Integration with AWS

Direct Connect delivered stable, private connectivity for production workloads.

✔ 99.99% Uptime Across Branches

Redundant routers, firewalls, and WAN links minimized downtime.

✔ Scalable for Future Growth

New branches and cloud services can be onboarded without redesigning the network.

Conclusion

The modernized network architecture created a resilient, secure, and scalable hybrid ecosystem, enabling the financial services enterprise to operate seamlessly across multiple cities while maintaining reliable access to core banking and AWS production systems. This foundation positions the organization for continued growth, improved operational efficiency, and enhanced customer service.