MICSO uses a network in SDH / DWDM technology and a network in IP/ MPLS technology, both of them extended at European level. The physical layer of both networks is made of an optical fibre infrastructure.

As a matter of fact the network in SDH / DWDM technology, apart form constituting a platform on which it is possible to provide services of pure connectivity at high capacity, serves also as an infrastructure of access and transport of IP/MPLS backbone.

The distiguishing characters of the network are mainly:

• the extension all over Europe with 23,000 km of infrastructure
• the capillary presence in the main European cities

Afterwards a short description of the network infrastructure is reported


Figure 1. Fibre optic network infrastructure

The topological structure of the transmissive network is the ring structure typical one, to guarantee a high reliability of service in case of failure; the ring network structure, which foresees diversified physical pathways for the two branches of the ring has a total loss of the service only if two failures on the ring take place contemporarily.
The level of availability of the service that MICSO guarantees is in the order of 99.98%.

The technologies presented to build the transmissive network are:

• DWDM- Dense Wavelength Division Multiplexing
• SDH (Synchronous Digital Hierarchy)

The total capacity transportable on the DWDM dorsal is that of wavelengths at 10 Gbps (STM64) on a single pair of fibres

Backbone IP MPLS

The MPLS IP network is made up of Cisco technology and uses the optical Ciena WDM layer dedicated to IP (IP over WDM) for the transport at the backbone level. The core nodes of the MPLS network are found in London, Frankfurt, Amsterdam and Paris with access nodes in the main European cities. The network structure is reported in the following scheme



Figure 2 . MPLS IP Network

The fiber optic network is also present in the main European Internet exchanges such as MIX in Milan, SFINX in Paris and LINX in London, with active peering sessions with the main service providers.

In particular, there are 374 active peering sessions with 298 different operators.

The peering connection at MIX in Milan has 2.5 Gbps capacity.

IP MPLS network performance is:

> 99.9% packet delivery
< 40ms European RTD