| MRV Products Upgrading FDDI to Gigabit Ethernet  The Fiber Distributed Data Interface (FDDI) protocol has been in common use in network backbones for a decade. FDDI provides a shared 100Mbps connection amongst many nodes using a ring topology. In most cases, individual hosts are connected to this backbone through bridges that attach many 10Mbps Ethernet connections to the 100Mbps FDDI backbone. FDDI allows ring-length to be up to 2km in distance, over multimode fiber-optic cabling, and is in common use in campus Enterprise backbones, especially in the government and financial industries. Most installations also use a redundant ring for backup purposes. As application bandwidth has grown over the last decade, FDDI networks have been unable to scale to match the requirements. Today it is necessary to have well over 100Mbps on the network backbone, and so switched Gigabit Ethernet is a common choice to leave room for future growth. Unfortunately, the distance limitation over multimode fiber using Gigabit Ethernet is 550m, when using standard fiber-optic interface types. MRV has developed a unique technology, Gigabit Multimode Extension (GMX), which actually couples enough power into multimode fiber to run Gigabit Ethernet to distances of well over 2km. This simple yet powerful technology actually allows Gigabit Ethernet to be a drop-in replacement for FDDI. Without GMX, the network infrastructure must be replaced; that is, multimode fiber-optic cabling must be switched to single-mode fiber-optic cabling. In addition, typical single-mode Gigabit Ethernet prices are much higher than GMX prices, allowing both a cost-elimination in the fiber-optic cabling and a cost-reduction in the network equipment itself. MRV's OptiSwitch family of switching and routing products, as well as the FiberDriver line of physical layer products provide GMX technology to bypass the limits of traditional multimode fiber. Gigabit Ethernet technology by itself does not provide the ring-redundancy that FDDI provides, however MRV offers a wide range of standards-based redundancy protocols, including Rapid Spanning Tree for a fast fail-over to backup fiber-optic connections. Since typical FDDI networks have 2 fiber-optic pairs running from each device to the next in the ring, it is quite simple to use redundant Gigabit Ethernet connections. MRV also provides optical fail-over equipment to protect the individual fiber-optic connections and cables. Optionally, the network administrator can choose to use Link Aggregation technology instead of redundancy technology to interconnect the devices. Using Link Aggregation, the fail-over capability still exists, but the secondary link is kept active to supply extra backbone bandwidth. When upgrading from FDDI to Gigabit Ethernet, one must be sure to check the fiber-optic distances and make decisions about what kind of topology and redundancy to implement. If the distances from device to device are small enough, standard Gigabit Ethernet (1000Base-SX) technology is sufficient. For larger distances, MRV provides the unique GMX technology to extend each link up to 2km. MRV equipment also provides a wide range of topologies and redundancy protocols, either at Layer-2 or Layer-3, allowing a seamless upgrade to connect the 10Mbps, or even 100Mbps end-stations to a Gigabit Ethernet backbone. This solution removes the backbone bottleneck and even allows room for future growth without any change to the network infrastructure. To find out more about MRV GMX solutions, contact your MRV sales representative, at sales@americanteledata.com. |
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MRV Products By Category  Out-of-Band Console & Power Management Pluggables Wave Division Multiplexing By Product Line OptiSwitch TereScope |
