Juniper Networks M20 User Manual
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This guide provides an overview and description of the Physical Interface Cards (PICs)
supported by the Juniper Networks M20 Internet router that are end-of-life and can
no longer be ordered. The PICs are described alphabetically. Table 1 on page 3 lists
the end-of-life PICs supported by the M20 Internet router by PIC family.
PICs provide the physical connection to various network media types. The PICs are
mounted on Flexible PIC Concentrators (FPCs), which are inserted into a slot in a
router. A PIC typically occupies a single slot on an FPC. PICs receive incoming packets
from the network and transmit outgoing packets to the network. During this process,
each PIC performs framing and high-speed signaling for its media type. Before
transmitting outgoing data packets, the PICs encapsulate the packets received from
the FPCs. Each PIC is equipped with a media-specific ASIC that performs control
functions tailored to the PIC's media type. For complete information about installing
PICs and transceivers, see the PIC and Transceiver Installation Instructions located at
Blank PICs resemble other PICs, but do not provide any physical connection or
activity. When a slot is not occupied by a PIC, you must insert a blank PIC to fill the
empty slot and ensure proper cooling of the system.
NOTE: A single FPC slot has a maximum throughput of 3.2 Gbps. Inserting a
combination of PICs with an aggregate higher than that is supported, but constitutes
oversubscription.
Blank PICs resemble other PICs, but do not provide any physical connection or
activity. When a slot is not occupied by a PIC, you must insert a blank PIC to fill the
empty slot and ensure proper cooling of the system.
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M20 Internet Router PIC Guide: End-of-Life PICs