Vodovody a kanalizace Hradec Králové, a.s. (VAK HK, a.s.) is a municipally owned water utility company that is responsible for clean water supply and wastewater disposal. With its headquarters in Hradec Kralove in the East of Czechia, it provides water utilities to over 170,000 inhabitants using more than 1350 km of pipes and 550 km of sewers. VAK HK, a.s. infrastructure is operated by Královéhradecká Provozní, a.s. a member of the global Veolia group.
The legacy communications network, used to help manage its resources, used CONEL CDA radio modems with serial RDS protocol. Because of the end of support for all CONEL based devices, VAK HK, a.s. used this as an opportunity to source a modern, robust, IP network to provide reliable data communications now and in the future.
Current and future requirements were analysed and it was agreed the optimal solution would be best achieved using a Hybrid network with fully redundant data centres. In order to minimize disruption at any time during installation, the choice of Migration solution was also an important factor.
After comparing available options from different manufacturers, VAK HK, a.s. quickly realised that RACOM products and solutions ticked all the boxes.
The RipEX Radio modem and M!DGE Cellular router, both market leaders in their fields, share many SW and logic features. A central RipEX manages the routing of traffic, so an application can be implemented with one network interface. RipEX and M!DGE make ideal bed partners in any Hybrid network.
The RACOM Migration solution, too, is designed to ensure there is no network outage and that migration can be implemented as part of a regular maintenance program. And RACOM also manufacture the cabinets required to house all the new equipment – A complete one stop shop!
During migration, VAK HK, a.s. opted to use a parallel operation of legacy radios and RipEX, set up using two frequencies. Key repeater points were equipped with a duplexer allowing the network to operate on both frequencies simultaneously; one for the legacy network and the second for traffic on the RipEX.
27 primary sites, identified as critical infrastructure, are now equipped with M!DGE and RipEX working in parallel, making use of the RipEX Backup routing functionality to achieve high accessibility.
As the RipEX radio segment provides the highest availability, legacy RTU’s are connected to RipEX. However, when RipEX backup routing recognises there is an LTE connection available, traffic is routed through M!DGE to make best use of the connection. The M!DGE segment uses GRE tunneling within a private APN segment, terminated to a Cisco ASR box in the customer’s server house. This set up provides near 100% site connection availability.
An additional 69 points, identified as secondary sites, are radio only and have been migrated to RipEX with the legacy RDS serial or Modbus TCP protocol.
All the equipment is housed in cabinets, manufactured and supplied by RACOM.
Phase two of the project, already planned, will include two fully redundant data centres at different locations in case there is ever a need for disaster recovery. A private MPLS customer network will also be established to interconnect the data centres and relay points.
