The advent of (very) high bitrate services, the availability of high bandwidth transmission systems, and the advantage of ATM statistical mulitplexing gain offered by Gbit/s switches, raise the need for high speed switching and make the exploitation of advanced system concepts and technological advances inevitable.
The first objective of the project is to study the feasibility of 2.4 Gbit/s ATM switching based on the ROXANNE Multi Path Self Routing switching principle.
The second objective is the demonstration of the possibilities of a new electro-optical interconnection technology to solve the interconnection problems inside broadband exchanges.
The main objectives of the research were:
demonstration of asynchronous (ATM) switching at 2.4 gigabits per second based on the ROXANNE multipath selfrouting switch;
demonstration of the potential of a new electrooptical interconnection technology to solve interconnection problems inside broadband exchanges.
Key issues in the research include:
high speed and high density digital signal processing;
high speed and high density interconnection and packaging;
precision mechanics for fibre to fibre and fibre to device alignment.
Achievements of the research include:
a feasibility study of 2.4 gigabits per second ATM switching based on the ROXANNE concept has been completed, down to the level of chip partitioning;
Research on electrooptical board technology, multifibre packaging, and multifibre connector proceeds as scheduled.
The study of 2.4 Gbit/s ATM switching is be based on the switching fabric developed for the RACE 1022 (RATT) demonstrator, and on the use of a new 2.4 Gbit/s line termination card. The RATT demonstrator is capable of switching ATM connections at speeds up to 155 or 622 Mbit/s. However, the switching fabric of the RATT can also accommodate higher external link speeds. Indeed, the multiple path characteristic of the switching fabric implies there is no rigid relation between the external link bitrate and the internal speed of operation of the elements of the switching fabric.
To solve the high speed and high density interconnection problems inside broadband exchanges, an advanced electro-optical interconnection concept is being developed. Using discrete wiring technology, glass optical fibres are embedded in multilayer laminate substrates to realise electro-optical boards and back panels. The board technology is completed by the development of multi-fibre packages, electro-optical surface mount assembly techniques, a high density board to ribbon cable and board to back panel optical connector.
The feasibility of fibre in board parallel optical links was shown in a working demonstrator. In the extension of the project, the manufacturability of the optical interconnection concept is studied. Micro-machining is used for the fabrication of multi-fibre alignment parts. A hands-free backpanel connector is being developed.
- High speed and high density digital signal processing.
- High speed and high density interconnection and packaging.
- Precision mechanics for fibre-to-fibre and fibre-to-device alignment.
- Pulling forward the introduction of broadband services in Europe by reduction of the cost per unit of bandwidth. Due to ATM statistical multiplexing gain, a switch at 2.4 Gbit/s can handle considerably more traffic than 4 switches at 600 Mbit/s or 16 switches at 150 Mbit/s.
- Increased interest in broadband ATM switching through its application to single services having bit rates up to 2.4 Gbit/s.
- Electro-optical interconnection technology should facilitate cost-competitive solutions for the implementation of large broadband switches, based on the combination of optical interconnections and electronic logic.
IP1 5PB Ipswich
IP1 5PB Ipswich
10040 Leini Torino