Cisco & Meraki specialists. Across the UK.
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Industrial Network Segmentation

Segment industrial devices and control systems with Cisco networks, documenting required traffic flows and protecting operations during approved changes.

Cisco Partner since 2009 Projects & ongoing support

Illustrative Cisco and Meraki network rack in a modern office
Your network. Properly considered.Design · Implementation · Support
1,000+

Devices supported
across the UK

20+

Client locations
supported

Nearly 8 Tbps

Traffic handled
at peak time

3 min

Average
response time

Average response is not a resolution time or a contractual guarantee. Support scope and response commitments are agreed for each engagement.

Industrial network segmentation limits which systems can talk to each other. The first step is to understand the traffic that production needs. We work with operational owners and equipment suppliers to map those flows. The result is a staged plan for Cisco-led network boundaries, with checks that new rules do not block essential work.

01

Cisco-focused engineering

Design around the platform, traffic and failure behaviour you actually operate.

02

Change with evidence

Use pre-checks, acceptance criteria and a documented route back.

03

Operational handover

Keep the configuration, diagrams and responsibilities understandable after delivery.

Build a defensible picture of required traffic

We start with process diagrams, supplier needs, switch records and approved traffic observations. Controllers, operator interfaces, historians, engineering stations and external maintenance systems may have relationships that are missing from an IT asset list. We identify those dependencies before proposing where to place a firewall or routed boundary.

Traffic observations need interpretation. A connection seen during one shift may not capture maintenance, start-up, failover or periodic reporting. We agree the observation period and ask equipment owners to identify infrequent but necessary activities. The resulting flow register distinguishes confirmed services from traffic that needs explanation, rather than permitting everything simply because it was observed once.

Illustrative enterprise Cisco network rack in a modern office environment
01Enterprise switching and routing, built to be operated.
Cisco PartnerCisco Partner
Cisco MerakiCisco Meraki
ISO 9001Quality management
ISO 27001Information security
Cyber EssentialsCyber Essentials
Cyber Essentials PlusCyber Essentials Plus

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Define zones that reflect operational ownership

Segmentation is more useful when its boundaries correspond to a process, trust level or maintenance responsibility. We consider equipment groups, production cells, engineering services and interfaces to the enterprise network. The terminology should remain understandable to the people who approve access and investigate incidents.

A separate VLAN can reduce a broadcast domain, while a VRF separates routing contexts; neither automatically supplies all the inspection or access restrictions a security need may need. We choose the enforcement mechanism for the actual boundary and document where authorised traffic is inspected, routed or simply switched.

Illustrative Cisco and Meraki fibre network rack with structured cabling
02Fibre, switching and the physical path behind the service.

A useful starting point

Not sure where to start?

Bring the requirement. We will help you define the engineering work.

Talk to a specialist

Treat shared services as explicit dependencies

Time services, name resolution, remote management, logging and data collection may need to cross several zones. Allowing broad access to a shared server can undermine the separation the design was intended to create. We find the specific destinations and service directions required by each group of devices.

Industrial demilitarised-zone arrangements may help mediate exchanges between operational and business systems. Their value depends on the services and controls actually implemented, not the label on a diagram. We clarify which team owns those intermediary systems and how a failure will affect production reporting or maintenance access.

Illustrative Cisco and Meraki equipment in organised data-centre racks
03Data-centre connectivity with clear physical and logical boundaries.

Select controls supported by the estate

Cisco switching, routing, identity-based policy and firewall services offer different ways to apply separation. We check platform, software and feature support before recommending a particular method. A design that assumes every older controller can authenticate like an office laptop is likely to create exceptions that weaken the result.

Where device identity is limited, we assess the practical controls available at the connection and gateway. Exceptions should have a documented reason, owner and review condition. The aim is a workable improvement with known limitations, not an impressive policy diagram that operations must bypass to keep the plant running.

Illustrative Cisco and Meraki industrial network equipment in a plant environment
04Network engineering for operational and industrial environments.

Introduce restrictions in controlled stages

The rollout can begin with visibility and a limited pilot before enforcement expands. We agree test devices, change windows, app checks and rollback actions with the operational owner. A test must consider process state and simple network reachability: equipment may remain pingable while a required control exchange fails.

We avoid applying a broad deny rule across an unfamiliar estate as a demonstration of security. The sequence should show which flows are being protected, what evidence supports the rule and how the change will be reversed if a legitimate dependency was missed. Emergency exceptions remain recorded and subject to review after the incident.

Illustrative Cisco and Meraki data-centre network infrastructure
05Network infrastructure designed around the workloads it carries.

Validate both access and isolation

Acceptance includes proving that required communications still work and that chosen unauthorised paths are blocked. Tests need written authority and a method suitable for the connected systems. Intrusive scanning or penetration techniques are not assumed to be safe merely because the project concerns segmentation.

The evidence can support a customer’s wider assurance programme. But it is not a blanket certification of the operational setup. Safety, process governance and regulatory obligations require their own assessment. We state exactly which network boundaries were tested and which conditions remain outside the agreed scope.

Illustrative Cisco and Meraki network rack in a modern office
06The office network: switching, uplinks and structured cabling.

Keep the segmentation current

New equipment, temporary vendor access and changes to data collection can gradually erode a well-designed boundary. We recommend a change process linked to the flow register, with an owner for each exception. Diagrams and policy records should be updated when the live network changes, not saved for an annual documentation exercise.

MCI can assess a current industrial network or develop segmentation alongside a planned network migration. The outcome is an agreed set of operational zones, permitted flows, enforceable controls and evidence that your team can use to maintain the separation after the project ends.

Illustrative enterprise Cisco network rack in a modern office environment
07Enterprise switching and routing, built to be operated.

Talk to a specialist

What does your network need next?

Tell us what you are planning, changing or trying to improve. We will help define a practical next step and the engineering scope.

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