Modernizing a Mission-Critical Air Traffic Management Network with Secure IP/MPLS
Overview
A national air navigation service provider responsible for safe and reliable air traffic management across an entire country needed to migrate from a legacy TDM-based communications network to a modern IP/MPLS WAN. The new network would interconnect control towers, area control centers, radar installations, navigation aids, and administrative offices while carrying a diverse mix of voice, data, and legacy TDM services with stringent availability and security requirements.
A leading IP networking vendor was selected to design and deploy the nationwide IP/MPLS infrastructure using service aggregation routers with native support for Ethernet, TDM, analog voice, and serial data interfaces — all over a single converged platform with end-to-end encryption.
The Challenge
- Migration from legacy TDM infrastructure to IP/MPLS while maintaining uninterrupted air traffic management services
- Transport of analog voice (E&M signaling), serial data (SDI), E1 circuits, and IP traffic over a single converged network
- Mandatory Network Group Encryption (NGE) on all services to meet aviation security and regulatory requirements
- Precise timing synchronization using IEEE 1588v2 for operational systems that depend on accurate time references
- Diverse physical topology using a mix of leased fiber circuits, DWDM connections, airport fiber facilities, and microwave radio backup links with speeds from 300 Mbps to 1 Gbps
30+ Network Sites
7 Service Types
End2End Encryption
The Solution
Network Architecture
A ring-based IP/MPLS topology was deployed using a mix of high-density and standard service aggregation routers across the nationwide footprint. Core links operated at 1 Gbps over leased DWDM fiber, with microwave radio providing 300 Mbps backup at select sites. OSPF with traffic engineering extensions served as the IGP within a single area, while RSVP-TE LSPs with CSPF and FRR provided protected MPLS transport. BGP route reflectors enabled scalable VPRN service distribution without requiring a full iBGP mesh.
Service Delivery
Seven distinct service types were deployed across the network: analog E&M voice circuits transported as Cpipe TDM pseudowires, serial data interfaces (SDI) for legacy radar and navigation equipment, E1 circuits for inter-facility links, a dedicated C-NET VPRN for operational air traffic control communications, an Office Network VPRN for administrative traffic, a 6VPE VPRN for IPv6 transition, and Epipe services for point-to-point Ethernet connectivity. Each service type was assigned a dedicated customer ID and service ID range for operational clarity.
Network Group Encryption
All services traversing the IP/MPLS backbone were encrypted using Network Group Encryption (NGE), providing AES-256 encryption at the MPLS layer. Encryption keys were centrally managed through the network management platform with automated key rotation. The encryption architecture required careful MTU planning to accommodate the additional NGE overhead (approximately 56 bytes) across all transport links.
Synchronization & QoS
IEEE 1588v2 was deployed end-to-end for precise clock synchronization, critical for air traffic management operations. A seven-class DiffServ QoS model prioritized voice and control signaling above data traffic, with 16-priority scheduling on network ports and 4-priority scheduling on access ports.
Results
- Successfully migrated national air traffic management communications from legacy TDM to a converged IP/MPLS platform without service interruption
- Delivered seven distinct service types including analog voice, serial data, E1, and multiple IP VPN services over a single infrastructure
- Implemented end-to-end AES-256 encryption on all services using Network Group Encryption, meeting stringent aviation security requirements
- Achieved precise network synchronization via IEEE 1588v2 for time-critical air traffic control operations
- Established a scalable, ring-based topology with diverse fiber and microwave paths providing resilient nationwide connectivity