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Switching Technology

Demand for network bandwidth continues to grow, driven by the increasing number of systems used in network-intensive applications. LAN segmentation has been the prevalent method for addressing these demands and has been further popularized by trends toward server centralization. However, the implementation costs of LAN segmentation, as well as the real performance characteristics of conventional network components, have served to limit growth of some Token- Ring networks. Alternative technologies for addressing bandwidth demands present yet other inhibitors, usually relating to costs. Token-Ring switching provides users with an easy, cost-effective technique for addressing these demands.

Token-Ring switches, such as the CrossFire 8600 and the CrossFire 8605, increase throughput between Token-Ring segments by supporting simultaneous, parallel conversations. Switched connections between Token-Ring segments last only for the duration of the packet—new connections can be made between different segments for the next packet.

Token-Ring switches solve congestion problems caused by high-bandwidth devices and powerful applications as well as the number of users. Therefore, each of these devices—servers, for example—can be assigned its own 16 Mbps segment.

In Token-Ring networks, the major bottleneck is typically the throughput to high- bandwidth devices such as servers, and between routers, bridges, and switches. An effective solution is full-duplex communication, an option for each segment connected to a CrossFire 8600 or a CrossFire 8605 port. Normally, Token-Ring operates in half-duplex communication mode, which means stations can either receive or transmit. With full-duplex technology, two communicating stations can transmit and receive at the same time. When packets can flow in both directions simultaneously, effective Token-Ring bandwidth doubles from 16 Mbps to 32 Mbps.

The CrossFire 8600 and the CrossFire 8605 can forward Token-Ring frames among multiple, shared or dedicated Token-Ring LAN segments. Using a frame forwarding technique similar to that of a multiport Token-Ring transparent bridge, the switch uses Token-Ring MAC addresses to forward Token-Ring frames from any of its ports to any other.

Switch of Switches

The CrossFire 8600 and the CrossFire 8605 can be deployed in a variety of network configurations, all of which provide a significant increase in network performance. The series of Olicom Token-Ring products allows users to build network systems that can transport data efficiently and scale upwards as throughput requirements increase. The switches deliver high-reliability and media flexibility. These features combine to allow the switches to be used as a switch of switches which provides media flexibility in an Token-Ring configuration.

CrossFire 8600/8605 Token-Ring Switches v. 1.2, P/N: 710001641

Overview and Specifications

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Olicom 8605, 8600 manual Switching Technology, Switch of Switches