Resilient Packet Ring
Resilient Packet Ring (RPR) is a relatively new network technology that was specified by the IEEE standard 802.17 . It is a network protocol that was specially designed for the optimized transport of data traffic over fiber optic rings. A key aspect in defining the protocol was to take advantage of the pronounced self-healing ability of SONET / SDH networks. This important performance feature makes it possible, in the event of line interruptions, to switch over to an alternative route automatically and quickly (switchover time within approx. 50 ms). But instead of - as with SONET / SDH - relying on line- oriented connections, the RPR concept is based on packet-oriented connections for data transmission , which is intended to increase the performance of Ethernet and IP-based services.
Development history
The development of RPR was primarily initiated by the fact that the TCP / IP protocol family, a packet-oriented transmission technology, had established itself. The effects associated with this generation change, however, increasingly led to an increasingly inefficient use of the available transmission capacities. The reason for this lay in the insufficient coordination between the previous classic (line - oriented ) transmission technologies in the two lowest layers of the OSI reference model and the new packet-oriented technologies that are based on the services offered by these layers. With the implementation of RPR, this deficiency in the architecture design is to be eliminated and a more resource-saving combination of the previously divergent technologies achieved. The use of RPR therefore has several advantages for the operators of wide area networks:
- a more efficient use of the available transmission capacities
- the standardization of the network architecture used
- the optimization of operational processes
characterization
The network architecture on which the RPR is based consists of two opposing transmission rings, the so-called ringlets (also known as ringlets). These ringlets are formed by the implementation of RPR stations and nodes and work in opposite directions, i.e. H. the data flow in the two rings takes place in opposite directions. This has the advantage that after a ring is interrupted, a short circuit can be made between the two rings and the data stream affected by the fault can be diverted to the other ring.
Web links