Principal Network Architect

CACI Ltd; Greater London; On-site; GBP 120,000 - 160,000; Full time

Job summary

CACI Network Services is a rapidly expanding IT and networks consultancy. As Principal Network Architect, you will act as trusted advisor, technical authority, and strategic partner to our clients, leading the design of complex, secure, scalable network architectures.

You will work with sales, delivery teams, engineering and senior stakeholders, guiding engagements from concept to design, delivery oversight and operational readiness, with emphasis on pre-sales support and architectural

Qualifications

• Experience designing and delivering large-scale network and security solutions.
• Strong understanding of network architecture and security principles.
• Experience acting as Design Authority on complex engagements.
• Proven pre-sales, tender responses, and solution shaping experience.
• Ability to communicate complex concepts to non-technical stakeholders.

Responsibilities

• Lead design of secure, scalable network architectures across major programmes.
• Engage with stakeholders from C-level to technical teams to translate requirements.
• Produce high-quality architectural documentation (HLA, HLD, LLD).
• Partner with Sales on pre-sales engagements and tender responses.
• Provide technical leadership during delivery and ensure architectural intent.

Skills

Large-scale network solutions

Security architectures

Pre-sales experience

Design Authority

Architecture leadership

Tools

Python

Ansible

Terraform

Job description

About Network Services

CACI Network Services is a rapidly expanding specialist IT and Networks consultancy offering a wide variety of opportunities to work within challenging and exciting environments with our major clients in Global Media, Banking, Government, Telecoms & Utilities.

The Role

As a Principal Network Architect, you will be a trusted advisor, technical authority, and strategic partner to our clients. You will lead the design of complex, secure, and scalable network architectures, translating business requirements into robust technical solutions. This role combines technical leadership, solution architecture, consultancy, and pre‑sales engagement, requiring a strong ability to operate at both strategic and hands‑on levels.

You will work closely with customers, sales, delivery teams, engineering functions, and senior stakeholders—guiding engagements from initial concept through to detailed design, delivery oversight and operational readiness.

Key Responsibilities

Client Engagement & Consultancy

• Operate as a trusted advisor for key clients and prospective customers (new logos).
• Engage with stakeholders from C‑level executives to technical engineering teams, translating complex technical and business requirements into high‑level and detailed technical architectures.
• Provide expert consultancy on network strategy, transformation roadmaps, best practices, and emerging technologies.
• Build strong, long‑term relationships that support account growth and customer satisfaction.

Technical Leadership & Architecture

• Act as the Design Authority across major programmes, owning the end‑to‑end technical vision from inception through transition to operations.
• Architect network solutions across environments of varying scale—from small to mid‑sized infrastructures through to highly complex, large‑scale enterprise and multi‑site architectures—covering LAN/WAN, Wireless, routing, switching, SDN, and security technologies. Ensure all designs are scalable, resilient, secure, and aligned to customer requirements, technical strategy, and industry best practices
• Lead creation of high‑quality architectural documentation, including HLA, HLD, LLD, standards, and design patterns.
• Ensure designs align with industry best practices, compliance requirements, and customer governance processes.
• Partner with the Sales team during pre‑sales engagements to define solutions, scope opportunities, and support commercial proposition development.
• Lead technical responses for Tenders, IITs, and RFPs, including architecture design, technical writing, risk identification, and pricing model support.
• Present proposed solutions to senior client stakeholders with clarity, confidence, and technical authority.

Collaboration & Delivery Oversight

• Work alongside multi‑disciplinary delivery teams, providing leadership, technical guidance, and assurance during implementation phases.
• Support project managers and engineering teams to ensure solutions are delivered in line with architectural intent and to the highest quality.
• Contribute to internal knowledge sharing, capability development, and practice maturity across the organisation.
• Contribute to the identification, design, and development of innovative internal products, frameworks, and service offerings that enhance CACI’s strategic advantage, improve delivery efficiency, and support growth across key market sectors.

Across a broad and evolving technology landscape, including:

• Enterprise LAN/WAN, SD‑WAN, SDA and Wireless architectures
• Data Centre end to end solutions
• Routing & switching technologies
• Software‑defined networking solutions
• Cloud networking (AWS / Azure / GCP / OCI) – highly desirable

What We’re Looking For

Technical & Professional Expertise

• Proven experience designing and delivering large‑scale network and security solutions across enterprise or service provider environments.
• Deep understanding of network architecture principles, high availability design, routing protocols, segmentation, security architectures, and cloud networking.
• Experience acting as the final technical authority or Design Authority on complex engagements.
• Strong background in pre‑sales, tender responses, and solution shaping.
• Ability to clearly articulate complex technical concepts to non‑technical audiences and senior stakeholders.

Consultancy & Communication

• Excellent interpersonal, written, and verbal communication skills—capable of producing well‑structured technical documentation and delivering impactful presentations.
• Ability to engage with business stakeholders and end‑users to diagnose issues, propose solutions, and provide strategic recommendations.
• Comfortable representing the organisation independently, with a focus on delivering outstanding customer experiences.

Ways of Working

• Demonstrably collaborative approach when working with sales, engineering, and delivery functions.
• Self‑sufficient, proactive, and comfortable working in high‑pressure environments.
• Experience working within Agile / Scrum, Waterfall, and hybrid project delivery methodologies.
• Strong commitment to continuous learning and staying ahead of industry advancements.

Desirable Certifications & Skills

(Certifications not required but advantageous)

• CCNP / CCIE, JNCIP / JNCIE, or equivalent expert‑level certifications
• Security vendor certifications from platforms such as Fortinet (NSE), Palo Alto (PCNSE/PCNSA), Cisco Security (CCNP Security/CCIE Security), and Check Point (CCSA/CCSE).
• Cloud certifications (AWS/Azure/GCP/OCI)
• Strong understanding of structured delivery and operational frameworks (ITIL, PRINCE2, AgilePM, or similar project/service management certifications)
• Experience with automation tools (Python, Ansible, Terraform, etc.)