Senior Networking & Security Specialist

CBSbutler Holdings Limited trading as CBSbutler; Newbury; Hybrid; GBP 130,000 - 156,000; Full time

Job summary

CBSbutler seeks a Senior Networking & Security Specialist/Technical Lead to steer design and hands-on implementation of complex network and security projects across enterprise environments in a hybrid Newbury setting.

You will lead technical delivery, create comprehensive designs, and mentor engineers, while engaging with stakeholders throughout project lifecycles.

Qualifications

• Extensive hands-on design and implementation of complex network and security solutions.
• Experience across enterprise environments, multi-vendor, multi-site.
• Strong ability to produce high-level and low-level designs and runbooks.

Responsibilities

• Lead design and implementation of complex network and security solutions across environments.
• Produce high-quality HLDs, LLDs, implementation plans and runbooks.
• Perform design validation, PoC testing and verification post-implementation.
• Configure, deploy and optimise network and security infra.
• Diagnose and resolve complex incidents.
• Conduct capacity planning and technical assessments.
• Act as primary technical contact for stakeholders.
• Present designs to technical and non-technical audiences.
• Coordinate engineers and provide technical leadership and mentoring.
• Collaborate with project managers, architects, client teams and operations.

Skills

Networking

Routing & Switching

BGP

OSPF

IS-IS

EIGRP

VLAN

STP/RSTP/MSTP

vPC/LACP

QoS

VXLAN

GRE

IPsec

Cisco ACI

spine-leaf architecture

Job description

Senior Networking & Security Specialist / Technical Lead

Location: Newbury - Hybrid, 1-2 days per week onsite

Contract: 6 months rolling

Security Clearance: Active or eligible for UK SC Clearance

Rate: £500-£600 per day, inside IR35

We are looking for an experienced Senior Networking & Security Specialist / Technical Lead to join a high-level technical delivery team, leading the design and hands-on implementation of complex, multi-vendor network and security solutions across enterprise environments.

This is a hands-on role combining technical leadership, solution design, implementation and stakeholder engagement.

Key Responsibilities

• Lead the design and implementation of complex network and security solutions across greenfield and brownfield environments
• Produce high-quality HLDs, LLDs, implementation plans and operational runbooks
• Perform design validation, PoC testing and pre/post-implementation verification
• Configure, deploy and optimise network and security infrastructure
• Diagnose and resolve complex network and security incidents
• Conduct technical assessments and capacity planning
• Act as the primary technical point of contact for project stakeholders
• Present technical designs and implementation strategies to technical and non-technical audiences
• Coordinate engineers and technicians, providing technical leadership and mentoring
• Work closely with project managers, solution architects, client teams and operations throughout the project lifecycle

Technical Experience Required

• We're particularly interested in candidates with strong experience across:
• Networking
• Advanced routing & switching
• BGP, OSPF, IS-IS and EIGRP
• VLAN, STP/RSTP/MSTP, vPC/LACP and QoS
• VXLAN, GRE and IPsec
• Enterprise and service-provider environments
• Cisco ACI, including spine-leaf architecture and multi-pod/multi-siteNetwork Security
• Next-Generation Firewall design and implementation
• IPsec, SSL/TLS and SD-WAN security
• Security policy and lifecycle management
• Compliance-aligned network securityApplication Delivery
• L4/L7 load balancing
• SSL offloading
• Global Server Load Balancing (GSLB)
• High-availability architecturesVendor Technologies
• Cisco IOS/IOS-XE/IOS-XR/NX-OS, ASA, Firepower, ISE, Catalyst Centre and ACI
• Juniper JunOS and SRX
• Fortinet FortiOS, FortiGate, FortiManager and FortiAnalyzer
• F5 BIG-IP LTM/GTM/ASM/APM and iRules

Desirable

• Network automation experience using Python and/or Ansible
• Experience integrating network platforms via REST/NETCONF/RESTCONF/gRPC APIs
• Professional-level networking certifications such as CCIE, JNCIE or equivalent
• Cisco DevNet certification

What We're Looking For

You'll need to be a confident technical lead who can take ownership of complex deliverables, communicate technical concepts clearly, solve problems under pressure and work effectively with both technical and business stakeholders.

If you're an experienced Network & Security Specialist looking for your next contract opportunity in a technically challenging environment, we'd love to hear from you.