Connect. Secure. Manage.
Catalyst Core and Distribution
Build Cisco campus core and distribution layers with clear fault boundaries, predictable forwarding paths and capacity for planned business growth.
Devices supported
across the UK
Client locations
supported
Traffic handled
at peak time
Average
response time
Average response is not a resolution time or a contractual guarantee. Support scope and response commitments are agreed for each engagement.
Catalyst core and distribution networks carry traffic between floors, buildings and data centres. They need enough capacity and a tested way to cope with faults. We plan the routing, power and separate paths together. This helps you choose a design your team can run and maintain, without adding layers that the site does not need.
Cisco-focused engineering
Design around the platform, traffic and failure behaviour you actually operate.
Change with evidence
Use pre-checks, acceptance criteria and a documented route back.
Operational handover
Keep the configuration, diagrams and responsibilities understandable after delivery.
Decide whether a separate core is justified
Not every network needs three physical layers. A smaller campus may be better served by a collapsed core, while a larger or more geographically dispersed estate may benefit from separating access aggregation from backbone transport. We consider site geography, the number of access blocks, growth expectations, app dependencies and maintenance windows before choosing the topology.
The central question is what must remain available during a failure or planned change. If a distribution switch fails, which floors or services are affected? If a software upgrade requires a restart, can the remaining path carry normal traffic? We set out acceptable disruption with the customer, then select supported designs that can be tested against those expectations.
Standards & partnerships
Confidence in the team behind your network.
Cisco Partner
Cisco Meraki
Cyber Essentials
Cyber Essentials PlusMCI Network Services is operated by Proxar Ltd. Certifications apply to the certified legal entity and the scope of its certificates. View accreditation information
Layer 2 boundaries and Layer 3 routing
Extending VLANs through a campus can make initial rollout convenient but can also enlarge the impact of loops and spanning-tree changes. We assess where Layer 2 domains should end, where default gateways should sit and how routing should connect buildings and security zones. Routed access is not automatically the best answer; endpoint mobility, current systems and operational skills can influence the choice.
OSPF, IS-IS, BGP or other supported routing approaches may be appropriate in different setups. We document neighbour relationships, route summarisation, failure detection, redistribution boundaries and the expected path after a link failure. A routing protocol should not be chosen because it is fashionable. It should be chosen because its behaviour is understood by the team that will operate it.
A useful starting point
Not sure where to start?
Bring the requirement. We will help you define the engineering work.
Resilience requires independent failure paths
Two links are not necessarily resilient if they use the same fibre route, line card or upstream device. We review physical cabling, optic types, power supplies, rack distribution and maintenance dependencies. Where the platform supports virtualised switching or multi-chassis aggregation, we assess both the benefits and the shared-control-plane risks. Independent routed devices may provide clearer fault boundaries for some organisations.
We test convergence aims using realistic traffic. A control-plane adjacency returning to an established state does not prove that an app has recovered. Voice, transactional apps and market-data distribution can expose transient loss or asymmetry that a basic network access check misses. Acceptance tests should include representative traffic and documented recovery times rather than relying on theoretical platform claims.
Different environments. The same care.
Built around the work
your network supports.
Finance, banking and the wider private sector. We start with the systems and people that depend on your connections.
Finance & banking
Market-data paths, routing and provider coordination on clients’ behalf.
Financial-market services ↗Offices & multi-site teams
Reliable access between people, workplaces and business applications.
Office network design ↗Data centres & cloud
Network boundaries, workload connections and operational ownership.
Data centre networks ↗Capacity, optics and oversubscription
Core and distribution capacity planning should use observed usage and traffic patterns, not simply the aggregate speed printed on access-port labels. We consider uplink oversubscription, east-west traffic, firewall hairpinning, multicast replication and the effects of losing one member of a redundant path. An uplink that is comfortably sized during normal operation may become congested when its partner fails.
Optics and fibre infrastructure also need scrutiny. We confirm supported transceiver combinations, distances, fibre types, connector cleanliness and the availability of spares. Errors caused by marginal optical links can resemble routing instability or app faults. A sensible migration plan therefore includes physical-layer testing alongside setup validation.
Migration without unnecessary outage
A core refresh is not the place to discover undocumented dependencies. We inventory routed interfaces, static routes, routing peers, first-hop redundancy, access lists, multicast needs, management networks and any unusual app paths. We identify devices that may have hard-coded gateways or expect a particular source address. Those findings determine whether a parallel build, phased migration or tightly controlled cutover is appropriate.
Before changes, we capture settings, routing tables and relevant operational baselines. During the migration we check expected neighbours, prefixes, forwarding paths and app reachability. Rollback triggers are agreed in advance and supported by a practical way to restore the former path. A rollback plan that depends on unavailable hardware or untested access is not a credible safety measure.
Keep the design maintainable
A successful core is one that the customer’s team can understand and operate. We deliver logical and physical diagrams, addressing and routing documentation, platform support information and a record of design decisions. Monitoring should distinguish genuine loss of redundancy from harmless state changes. Configuration backups and change records should make it possible to investigate an incident without relying on the memory of one engineer.
MCI provides Cisco network design, installation and operational support throughout the UK, with a strong focus on London, Kent, Sussex, Essex and Berkshire. If you are replacing a campus backbone, integrating sites or investigating unstable routing, we can start with an architecture review and develop a rollout plan that reflects your actual service needs.
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.
+44 203 196 6566Choose option 1
sales@proxar.co.ukUK-wide service.
Most of our engineers are based in Kent, with a focus on London, Sussex, Essex and Berkshire.
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