B-4
Cabling and Technology Information
Mode Conditioning Patch Cord
The following information applies to installations in which multimode fiber-
optic cables are connected to a Gigabit-LX port or a 10-Gigabit LRM port.
Multimode cable has a design characteristic called “Differential Mode Delay”,
which requires the transmission signals be “conditioned” to compensate for
the cable design and thus prevent resulting transmission errors.
Under certain circumstances, depending on the cable used and the lengths of
the cable runs, an external Mode Conditioning Patch Cord may need to be
installed between the Gigait-LX or 10-Gigabit LRM transmitting device and the
multimode network cable to provide the transmission conditioning. If you
experience a high number of transmission errors on those ports, usually CRC
or FCS errors, you may need to install one of these patch cords between the
fiber-optic port in your switch and your multimode fiber-optic network
cabling, at both ends of the network link.
The patch cord consists of a short length of single mode fiber cable coupled
to graded-index multimode fiber cable on the transmit side, and only
multimode cable on the receive side. The section of single mode fiber is
connected in such a way that it minimizes the effects of the differential mode
delay in the multimode cable.
10-Gig LR single mode fiber N/A 2 - 10,000 meters
10-Gig ER single mode fiber N/A 2 - 40,000 meters
1
Cat 6 cabling requires TIA TSB-155A testing for 500 MHz operation and ANEXT.
2
For distances less than 20km, a 10dB attenuator must be used. For distances between 20km and 40km, a 5dB attenuator
must be used. Attenuators can be purchased from most cable vendors.
Table B-2. Technology Distance Specifications(Continued)
Technology Supported cable type Multimode fiber
modal bandwidth
Supported distances
To Next Page
Loading...
Need help?
General
