Introduction

Barton Willmore is the UK’s leading independent planning and design consultancy. With 12 offices nationwide Barton Willmore combines national influence with local knowledge to offer their customers the very best advice.


Nocsult consulted for Barton Willmore to help them migrate the branch offices off the expensive leased lines which were approaching the end of contract. The requirement was to lower the expenditure on leased lines, but also to increase available bandwidth in each branch across the country.


Basic Concepts

- Existing Network build across multiple locations in the UK;
- The main office in Reading reached capacity and was scheduled to be moved to a new location, over two floors;
- Cisco Equipment across the network;
- Expensive leased lines to used connect the branches into an MPLS cloud, mostly at 10Mbps;
- No redundancy for most branches, and any issue with the leased line meant the staff were unable to do their work;
- Existing internal VoIP infrastructure;
- Bandwidth capacity was approaching maximum, and often this meant congestion.


Project Requirements

- Decide on a solution that would provide redundancy, increased bandwidth and reduced cost;
- Test the solution in lab environment;
- Ability to run dynamic routing protocol across the core routers in each branch;
- Use the existing RFC1918 address space in each location;
- Deploy the core equipment in a DataCentre environment;
- Provide connectivity to more than 200 workstations in the new main office;
- Migrate the network to the new solution gradually, without downtime;
- Deploy SNMP monitoring, Netflow and Live Weather maps.


Design and Testing

Phase 1

- The chosen solution was DMVPN dual hub and spoke topology;
- Deploy and test DMVPN in lab environment;
- Create failover scenarios and analyze the failover times.


Phase 2

- Build the datacenter core and migrate the storage and main servers into the Datacentre;
- Deploy the core DMVPN routers into the datacenter;
- Deploy the two DMVPN spokes in the new main office, one on each floor;
- Install British Telecom and Virgin Media point to point gigabit lines from the new main office to the datacenter;
- Load balance on both lines, with each floor preferring the line terminating on that floor;
- Configure IPSLA probes for OSPF to act on line failure for either of the providers;
- Test routing scenarios and failover scenarios. The decision was made to use OSPF inside the customer network;
- Connect the main office into the DMVPN cloud, while also providing connectivity to the incumbent MPLS cloud for the remaining branches.


Phase 3

- Provision business broadband instead of point to point leased lines into branches;
- Migrate the rest of the branches into the DMVPN solution while maintaining connectivity to the existing MPLS cloud;
- Install two different broadband providers in each branch;
- Increase bandwidth capacity from 10Mbps per branch to 200Mbps using business broadband;
- Configure local internet breakout to distribute the internet access traffic;
- Connect the branches securely to the datacenter main servers;
- Upgrade busy offices to 10Gbps links with 1Gbps workstation access port;
- Open new offices and join them into the DMVPN solution;
- Deploy SNMP monitoring, Netflow, Alerting and Live Weather Maps;
- Deploy private monitoring probes across different offices.


Key Advantages

- WAN bandwidth increased from 10Mbps per office to 200mbps minimum;
- WAN redundancy means the company is not incurring a loss when one of the lines fails, as the failover re-routes traffic transparently for the users;
- New offices can be joined in a matter of minutes once the broadband is installed;
- More than 50% cost savings when compared to leased lines.