3Com 7000 manual The following pages describe each of these steps and give examples

116APPENDIX D: CABLING REQUIREMENTS

between any two communicating ATM devices and their connectors at each end.

To determine whether the cable plant complies with the SMF-PMD standard, do the following:

1Compare the specifications of the fiber you are using to standard specifications, as described in Table 29.

2If you mix equipment supporting Category 1 and Category 2, verify the maximum attenuation between the equipment, as described in Table 30.

The following pages describe each of these steps and give examples.

Comparing Fiber to Compare the specifications of the fiber you are using to those in Table 29. Specifications If the fiber does not meet the specifications, use a different fiber or

contact 3Com Technical Support.

The single mode PMD specification (SMF-PMD) defines two optical power categories: Category 1 and Category 2. These categories refer to the optical power that must be launched into the fiber by the transmitter or detected by the receiver. 3Com currently supports only Category 1 single mode fiber.

The specifications for the standard single mode fiber are listed in Table 29. Refer to the Category 1 specifications in this table for fiber connecting 3Com equipment. For fiber used with Category 2 equipment from another vendor, refer to the Category 2 specifications.

The cable plant for a Category 2 implementation must have a minimum loss of 15.0 dB. In a Category 2 implementation, minimum cable plant losses are required to avoid saturating (blinding) the receiver.

Table 29 Single Mode Fiber Specifications

Category	Specifications	Descriptions
Both Categories	Core	8 to 10 µm
	Cladding	125 µm (±2 µm)