Cabletron Systems ESX-1320 Installation Manual

Also see for ESX-1320: Management guide

Cabletron Systems ESX-1320 Installation Manual Manual pdf 59 page image

Multimode Fiber Optic NetworkESX-1320/ESX-1380 Installation GuideB-3B.3 MULTIMODE FIBER OPTIC NETWORKWhen connecting a multimode fiber optic link segment to the ESX-1380,ensure the network meets the following requirements:• Cable Type: Use the following multimode fiber optic media:- 50/125 μm fiber optic cabling- 62.5/125 μm fiber optic cabling- 100/140 μm fiber optic cabling• Attenuation: You must test the fiber optic cable with a fiber opticattenuation test set adjusted for an 850 nm wavelength. This testverifies that the signal loss in a cable falls within the followingacceptable levels:- 13.0 dB or less for a 50/125 μm fiber cable segment- 16.0 dB or less for a 62.5/125 μm fiber cable segment- 19.0 dB or less for a 100/140 μm fiber cable segment• Budget and Propagation Delay: When you determine the maximumfiber optic cable length to incorporate fiber runs into your network, youmust calculate and consider the fiber optic budget (a total loss of10.0 dB or less is permissible between stations) and total networkpropagation delay.To determine the fiber optic budget, combine the optical loss due tothe fiber optic cable, in-line splices, and fiber optic connectors.Typical loss for a splice and connector (together) equals 1 dB or less.Network propagation delay is the amount of time it takes a packet totravel from the sending device to the receiving device. Totalpropagation delay allowed for the entire network must not exceed25.6 μs in one direction (51.2 μs round trip). If the total propagationdelay between any two nodes on the network exceeds 25.6 μs, youmust use bridges or switches.• Length: The maximum possible multimode fiber optic cable length is2 km (1.24 miles). However, IEEE 802.3 FOIRL specifications specifya maximum of 1 km (0.62 miles).