Application Notes / Intelligent Transport Network for Traffic Infrastructure
The main purpose for implementation of an intelligent network along motorways
or railways is to ensure high traffic security. Along with other activities it can
be assured by:
- Remote control of messages on weather conditions on the route
- Crash warning systems
- Automatic accident reporting systems
- Video monitoring and announcing of traffic jams
- Remote control of security systems in tunnels (video monitoring,
fire and smoke alarms) and viaducts (wind, rain, snow, slippery ice, fog)
The second purpose is to ensure additional public services:
- Safety-related information
- Advance traffic control, signalization and navigation
- Advance electronic payment of motorway or train fees
- Advance parking management etc.
The third purpose of an intelligent networks is to ensure speech and data
communication between relevant access points and connections to the
public communication network.
For the most secure operation of peripheral devices for traffic control,
a reliable network must be established. The most commonly used one is BSHR with
section protection by two or four fibers. When two fibers are used, in the
case of section failiure, the traffic continues, but the traffic capacity
is halved. In the case, where four fibers are used, one pair of
fibers is intended only for the protection purpose; the protection is
therefore 100 %.
The ring can be divided into a backbone network and an access chain. The
backbone network ensures a high capacity traffic connection between
main cities or stations. The second task of the backbone network is to
ensure ring protection for the access chain. For that reason, the
transmission capacity of the backbone must be much higher in comparison with
the transmission capacity of the access chain.
Our proposal is:
- To built a backbone network by high capacity STM-16 SDH equipment (2.5 Gbit/s).
- The transmission capacity of the access chain can be lower:
155 Mbit/s (STM-1) It can be established by SparkLight.
- In the access points different tributaries of SparkLight
are available: STM-1, 45 Mbit/s, 34 Mbit/s or 2 Mbit/s. By using
Cross Connect and Flexible Multiplexers, different data protocols
(V.24, X.21, V.35, 10 BaseT/Ethernet) or services (ISDN, HDSL,
ADSL, SDSL) are accessible.
- If video transmission in some access points is expected, the
VU2 unit of Iskra Transmission can be inserted directly into the