Costello andamp; Reyes Group Ltd has been engaged by its client, an international consulting firm, to identify two DV Cleared Network Architects for a 6 month initial period based in Milton Keynes. There is significant scope for extension Network Architect YOU MUST HOLD VALID DV CLEARANCE! Role Purpose The Network Architect will be accountable for the end-to-end design, governance, and evolution of secure, resilient, and operationally sustainable network architectures across Microsoft Azure, Microsoft 365, hybrid cloud, and modern data-centre environments. The role spans IaaS, PaaS, and SaaS connectivity, VXLAN BGP EVPN, and identity-centric security architectures, ensuring tight integration between networking, identity systems, endpoint security, NDR, XDR, behavioural analytics, and incident response workflows. This is a design authority and strategy-defining role, supporting greenfield builds, Legacy network modernisation, and cyber-resilience uplift in line with modern threat landscapes and regulatory expectations. CCIE-level network architect with extensive hands-on experience across Cisco (Catalyst, Nexus, Meraki, ACI), Juniper, Aruba/HP and Arista. Proven delivery of large-scale end-to-end designs and implementations. Deep expertise in routing and core networking (BGP, OSPF, MPLS, VRF, SD-WAN, QoS, IPv6, Multicast, VoIP/CUCM), datacentre fabrics (Spine-Leaf, VXLAN, Nexus/ACI, Juniper QFX), wireless (Cisco/Aruba), and cloud networking across AWS, Azure and GCP ..... full job details .....