The RMDCN Project in RA VI

The Regional Meteorological Data Communication Network (RMDCN) provides a computer network infrastructure for the meteorological community in WMO Region VI. Over the years it has expanded to sites in WMO Region II.

• RMCDN Community Web Site (Login required)

Some history

In 1998 WMO RA (Regional Association) VI and the ECMWF council agreed to establish a common Managed Data Network, the Regional Meteorological Data Communication Network (RMDCN), as a cost-effective solution to replace the existing point-to-point links. They further agreed that ECMWF would lead and co-ordinate the procurement, implementation and operational monitoring of such a network for all RA VI Members. In December 1998 Equant was selected as the provider for the RMDCN. After the delivery and installation of the equipment at each NMC (National Meteorological Centre) and RTH (Regional Telecommunications Hub), connectivity and performance tests started for each PVC (Permanent Virtual Circuit) established between sites. On 15 March 2000 the RMDCN became operational. On 27 June 2002 the RMDCN contract was amended to allow Countries outside RA-VI to join the network.

The 2004 bi-annual contract review resulted in an offer from EQUANT to migrate to an MPLS based network. This proposal was approved by ECMWF council in December 2004. The other WMO members connected to the RMDCN also accepted the proposal for the migration. An amendment of the RMDCN contract, specifying the new service levels and the migration plan, was signed in May 2006. Immediately afterwards the implementation of the migration of the RMDCN to an IPVPN MPLS technology started. The new network was being rolled out in parallel to the existing network and on 16 April 2007 the acceptance phase started. After two months of extensive testing the new network was finally accepted on 18 June 2007.

RMDCN configuration

The network is based on the MPLS backbone infrastructure of Orange Business Services (OBS - a merger of Orange, Equant and France Telecom on 1 June 2006). This technology allows OBS to implement an IP Virtual Private Network (IPVPN) for the RMDCN community. The main characteristics for the new network are:

• It provides any-to-any connectivity between the RMDCN members.
• It provides a Gold or Silver Service Level:
• The Gold Service Level provides Class of Service mechanisms. Three Classes of Service have been defined: D1 class is for highest priority traffic and should get 75% of the bandwidth; D2 class is for medium priority traffic and gets 20% of the bandwidth and D3 class is for lowest priority traffic and gets 5% of the bandwidth. Please note that these bandwidth allocations only will take effect when the access circuit of a site is congested.
• It can provide Load Balancing for Mission Critical sites.
• Resilience is available in three options:
• Mission Critical: The site has got two diversely routed circuits to different OBS Points of Presence. The circuits are connected to two separate routers on the User Site.
• Extra Enhanced: The site has got two diversely routed circuits to different OBS Points of Presence. The two circuits are connected to the same router on the User Site.
• Enhanced: This uses the OBS NAS backup service which uses warm standby routers and ISDN dialup connections. This then creates a logical connection to the ECMWF routers which then acts as a gateway for the site into the IPVPN.

The new network connects 49 sites as listed in the following table.

An overview of the network configuration is shown in the following figure.

The following figure shows the global coverage.

In the framework of the WMO/ECMWF agreement on the RMDCN, the ECMWF project team manages the network and monitors the QoS (Quality of Service) on a 24-hour basis for all participating Centres. All the changes, new requests and connections affecting the network are co-ordinated by the project team. The manpower costs for these tasks are funded by the ECMWF Member States. The RMDCN web site provides the participating Centres with up-to-date information.