Received data enters a PLIM from the physical optical interface. The data is routed to the physical interface controller, which provides the interface between the physical ports, and the Layer 3 function of the MSC. For receive (ingress) data, the physical interface controller performs the following functions:

• Multiplexes the physical ports and transfers them to the ingress packet engine through the line card chassis midplane.
• Buffers incoming data, if necessary, to accommodate back-pressure from the packet engine.
• A GE PLIM provides Gigabit Ethernet specific functions, such as:
  • VLAN accounting and filtering database
  • Mapping of VLAN subports

The ingress packet engine performs packet processing on the received data. It makes the forwarding decision and places the data into a rate-shaping queue in the “to fabric” section of the board. To perform Layer 3 forwarding, the packet engine performs the following functions:

• Classifies packets by protocol type and parses the appropriate headers on which to do the forwarding lookup
• Determines the appropriate output interface to which to route the data
• Performs access control list filtering
• Maintains per-interface and per-protocol byte-and-packet statistics
• Maintains Netflow accounting
• Implements a flexible dual-bucket policing mechanism

The “to fabric” section of the board takes packets from the ingress packet engine, segments them into fabric cells, and distributes (sprays) the cells into the eight planes of the switch fabric. Because each MSC has multiple connections per plane, the “to fabric” section distributes the cells over the links within a fabric plane. The chassis midplane provides the path between the “to fabric” section and the switch fabric section.

The “from fabric” section of the board receives cells from the switch fabric and reassembles the cells into IP packets. The section then places the IP packets in one of its 8K egress queues, which helps the section adjust for the speed variations between the switch fabric and the egress packet engine.

The transmit (egress) packet engine performs a lookup on the IP address or MPLS label of the egress packet. The egress packet engine performs transmit side features such as output committed access rate (CAR), access lists, diffServ policing, MAC layer encapsulation, and so on.

The transmit packet engine sends the egress packet to the shaping and queuing function (shape and regulate queues function), which contains the output queues. Here the queues are mapped to ports and classes of service (CoS) within a port. Random early-detection algorithms perform active queue management to maintain low average queue occupancies and delays.

On the transmit (egress) path, the physical interface controller provides the interface between the MSC and the physical ports on the PLIM. For the egress path, the controller performs the following functions:

• Support for the physical ports.
• Queuing for the ports
• Back-pressure signalling for the queues
• Dynamically shared buffer memory for each queue
• A loopback function where transmitted data can be looped back to the receive side

As shown in Figure 2, the MSC contains a central processing unit (CPU) that performs the following functions:

• MSC configuration
• Management
• Protocol control

The CPU subsystem includes:

• A CPU chip
• A Layer 3 cache
• NVRAM
• A flash boot PROM
• A memory controller
• Memory, a dual in-line memory module (DIMM) socket, providing the following:
  • Up to 2 GB of 133 MHz DDR SDRAM on the CRS-MSC
  • Up to 2 GB of 166 MHz DDR SDRAM on the CRS-MSC-B
  • Up to 8GB of 533 MHz DDR2 SDRAM on the CRS-MSC-140G
  • Up to 15GB of 533 MHz DDR3 DIMM on the CRS-MSC-X (200G)

The CPU interface module, provides the interface between the CPU subsystem and the other ASICs on the MSC and PLIM.

The MSC also contains a service processor (SP) module that provides:

• MSC and PLIM power-up sequencing
• Reset sequencing
• JTAG configuration
• Power monitoring

The SP, CPU subsystem, and CPU interface work together to perform housekeeping, communication, and control plane functions for the MSC. The SP controls card power up, environmental monitoring, and Ethernet communication with the line card chassis RP cards. The CPU subsystem performs a number of control plane functions, including receipt of FIB downloads, local PLU and TLU management, statistics gathering and performance monitoring, and MSC ASIC management and fault-handling. The CPU interface drives high-speed communication ports to all ASICs on the MSC and PLIM. The CPU talks to the CPU interface through a high-speed bus attached to its memory controller.

The 1-port OC-768 PLIM provides an interface of 40 gigabits per second (Gbps), which is the OC-768 line rate. The PLIM performs Layer 1 and Layer 2 processing for an OC-768 data stream by removing and adding the proper header information as data packets enter and exit the PLIM.

The OC-768 PLIM is a class 1 laser product that operates in POS mode only; DPT mode is not supported. The PLIM contains:

• Optics module: Provides receive (RX) and transmit (TX) optic interfaces that comply with ITU Recommendation G.693. The module provides short-reach (SR) optics with SC fiber-optic interfaces.
• Framer: Provides processing and termination for SONET/SDH section, line, and path layers, including alarm processing and automatic protection switching (APS) support.
• Physical interface controller: Provides data packet buffering and Layer 2 processing, including processing for VLANs and back-pressure signals from the MSC.
• Additional components: Include power and clocking components, voltage and temperature sensors, and an identification EEPROM that stores initial configuration and PLIM hardware information.

The Cisco IOS XR software also provides diagnostic functions for the PLIM.

Figure 1 shows the front panel of the OC-768 PLIM.

The 1-port OC-768 PLIM has the following components:

• Single port (0) with SC fiber-optic interfaces for TX and RX.
• Three port LEDs that provide information about the status of the port:
  • ACTIVE: Indicates that the port is logically active; the laser is on.
  • CARRIER: Indicates that the receive port (RX) is receiving a carrier signal. The LED goes out (turns dark) if a loss-of-signal (LOS) or loss-of-frame (LOF) condition is detected.
  • RX PKT: Blinks every time a packet is received.
• STATUS LED: Green indicates that the PLIM is properly seated and operating correctly. Yellow or amber indicates a problem with the PLIM. If the LED is off (dark), check that the board is properly seated and that system power is on.
• Power consumption: 65 W

The OC-192 PLIM contains four ports that can be software configured to operate in packet-over-SONET (POS) or Dynamic Packet Transport (DPT) modes. The OC-192 PLIM provides Layer 1 and Layer 2 interface capabilities for four OC-192 data steams by removing and adding the proper Layer 1 and Layer 2 header information as data packets enter and exit the PLIM. The OC-192 PLIM feeds the MSC with one 40-Gbps data packet stream. The OC-192 PLIM has features described in Table 1.

Note	DPT mode is not available at this time.

The Cisco IOS XR software also provides loopback and diagnostic functions for the OC-192 PLIM.

The four different types of optics modules define the four major variants of the OC-192 PLIM:

• Long-reach (LR), Product ID: OC192-POS/DPT-LR=
• Intermediate-reach (IR), Product ID: OC192-POS/DPT-IR=
• Short-reach (SR), Product ID: OC192-POS/DPT-SR=
• Very-short-reach (VSR), Product ID: OC192-POS/DPT-VS=

Figure 1 shows the front panel of the three versions of the OC-192 PLIM.

Each 4-port OC-192 PLIM has the following components:

• Four ports (0, 1, 2, and 3) with TX and RX jacks for each port.
• STATUS LED: Indicates that the board is properly seated and operating OK.
• Five green LEDs for each port:
  • ACTIVE/FAILURE: Indicates that the port is logically active; the laser is on.
  • CARRIER: Indicates that the receive port (RX) is receiving a carrier signal.
  • RX PKT: Blinks every time a packet is received.
  • WRAP: Indicates that the port is in DPT wrapped mode.
  • PASS THRU: Indicates that the port is operating in the POS mode (DPT pass through).
• Two DPT MODE LEDs: One of these DPT MODE LEDs is for ports 0 and 1, and the other DPT MODE LED is for ports 2 and 3. The DPT mode is always configured on pairs of ports.
• Each 4-port OC-192 PLIM power consumption—138 W

The OC-48 PLIM comes in three different variants which can be software configured to operate in packet-over-SONET (POS) or Dynamic Packet Transport (DPT) mode. The 16xOC-48 PLIM contains 16 OC-192 interfaces and provides Layer 1 and Layer 2 interface capabilities, for 16 separate OC-48 data streams, by removing and adding the proper Layer 1 and Layer 2 header information as data packets enter and exit the PLIM. The 16xOC-48 PLIM feeds the MSC with one 40 Gbps data packet stream.

Table 1 describes the features of the 16xOC-48 PLIM.

The Cisco IOS XR software also provides loopback and diagnostic functions for the 16xOC-48 PLIM.

Figure 1 shows a 16xOC-48 PLIM.

Figure 2 shows the front panel of the OC-48 PLIM.

Each OC-48 PLIM has the following components:

• A STATUS LED: Indicates that the card is properly seated and operating OK.
• 16 ports with SFP optic modules for each port.
• Eight DPT MODE or POS MODE LEDs: One of these DPT MODE or POS MODE LEDs is for each pair of ports, 0 and 1, 2 and 3, 4 and 5, 6 and 7, 8 and 9, 10 and 11, 12 and 13, and 14 and 15. The DPT mode is always configured on pairs of ports. The LED is lit when a pair of ports are configured in the DPT mode. At this time, the 16xOC-48 PLIM operates only in the POS mode.
• Five green LEDs for each port:
  • ACTIVE/FAILURE: Indicates that the port is logically active; the laser is on.
  • CARRIER: Indicates that the receive port (RX) is receiving a carrier signal.
  • RX PKT: Blinks every time a packet is received.
  • WRAP: Indicates that the port is in DPT wrapped mode.
  • PASS THRU: Indicates that the port is operating in the POS mode (DPT pass through).
• Each 16xOC-48 PLIM power consumption—136 W

The 8-port 10-Gigabit Ethernet (GE) XENPAK PLIM provides from one to eight 10-GE interfaces. The PLIM supports from one to eight pluggable XENPAK optic modules that provide the 10-GE interfaces for the card. The PLIM performs Layer 1 and Layer 2 processing for up to eight 10-GE data streams by removing and adding the proper header information as data packets enter and exit the PLIM.

Although the PLIM can terminate up to 80 Gbps of traffic, the MSC forwards traffic at 40 Gbps. Therefore, the PLIM provides 40 Gbps of throughput, which it passes to the MSC as two 20-Gbps data packet streams:

• Ports 0 to 3 (the upper set of ports) provide 20 Gbps of throughput.
• Ports 4 to 7 (the lower set of ports) provide another 20 Gbps of throughput.

The 8-port 10-GE XFP PLIM supports from one to eight pluggable XFP optics modules. The 8-port 10-GE XFP PLIM has:

• Eight ports that accept XFP optics modules
• Status LED for the PLIM
• LED for each port

Note	For information about the XFP optical transceiver modules supported on the 8-port 10-GE XFP PLIM, see the Cisco CRS Carrier Routing System Ethernet Physical Layer Interface Module Installation Note.

The 8-port 10-GE XFP PLIM supports the following types of XFP optical transceiver modules:

• Single-mode low power multirate XFP module—XFP10GLR-192SR-L, V01
• Single-mode low power multirate XFP module—XFP10GER-192IR-L, V01

Cisco qualifies the optics that are approved for use with its PLIMs.

For the modules listed, use a single-mode optical fiber that has a modal-field diameter of 8.7 ±0.5 microns (nominal diameter is approximately 10/125 micron) to connect your router to a network.

Figure 1 shows the front panel of the 8-Port 10-GE XFP PLIM.

Table 1 describes the PLIM LEDs for the 8-Port 10-GE XFP PLIM.

The 8-port 10-GE XFP PLIM power consumption—88 W (with eight optics modules)

Table 2 provides cabling specifications for the XFP modules that can be installed on the 8-port 10-GE XFP PLIM.

The 4-port 10-GE XFP PLIM supports from one to four pluggable XFP optics modules. The 4-port 10-GE XFP PLIM has:

• Four ports that accept XFP optics modules
• Status LED for the PLIM
• LED for each port

Note	For information about the XFP optical transceiver modules supported on the 8-port 10-GE XFP PLIM, see the Cisco CRS Carrier Routing System Ethernet Physical Layer Interface Module Installation Note.

The 4-port 10-GE XFP PLIM supports the following types of XFP optical transceiver modules:

• Single-mode low power multirate XFP module—XFP10GLR-192SR-L, V01
• Single-mode low power multirate XFP module—XFP10GER-192IR-L, V01

Cisco qualifies the optics that are approved for use with its PLIMs.

For the modules listed, use a single-mode optical fiber that has a modal-field diameter of 8.7 ±0.5 microns (nominal diameter is approximately 10/125 micron) to connect your router to a network.

Figure 1 shows the front panel of the 4-Port 10-GE XFP PLIM.

Table 1 describes the PLIM LEDs for the 4-Port 10-GE XFP PLIM.

The 4-port 10-GE XFP PLIM power consumption—74 W (with four optics modules).

This table provides cabling specifications for the XFP modules that can be installed on the 4-port 10-GE XFP PLIMs.

The 1-port 100-GE CFP PLIM supports one pluggable CFP optics module.

The 1-port 100-GE PLIM has:

• One port that accepts a CFP optics module
• Status LED for the PLIM
• Four LED indicators for the single port
• The 1-Port 100-GE CFP PLIM power consumption—150 W

The 1-port 100-GE PLIM supports the following types of CFP optical transceiver modules:

• 100-GE pluggable optical transceiver module—CFP-100GE-LR4, V01

Cisco qualifies the optics that are approved for use with its PLIMs.

Figure 1 shows the front panel of the 1-Port 100-GE CFP PLIM.

Table 1 describes the PLIM LEDs for the 1-Port 100-GE CFP PLIM.

The CFP uses duplex single mode SC fiber cabling. Table 2 provides cabling specifications for the CFP modules that can be installed on the 1-Port 100-GE CFP PLIM.

Caution

A CFP optics module must be installed in the CFP transceiver module slot of each 100GE PLIM installed in the Cisco CRS chassis. The CFP transceiver module preserves the integrity of the card and is required for EMI and Safety compliance and proper cooling in the chassis.

The 20-port 10-GE XFP PLIM supports from one to twenty pluggable XFP optics modules.

The 20-port 10-GE PLIM has:

• Twenty ports that accept XFP optics modules
• Status LED for the PLIM
• Port status LED for each port

Note	For information about the XFP optical transceiver modules supported on the 20-port 10-GE XFP PLIM, see the Cisco CRS Carrier Routing System Ethernet Physical Layer Interface Module Installation Note.

Note	The 20-port XFP PLIM has a fixed power budget for the pluggable XFP optics. See XFP Optics Power Management for detailed information.

The 20-port 10-GE PLIM supports the following types of XFP optical transceiver modules:

• Single-mode low power multirate XFP module—XFP10GLR-192SR-L, V01
• Single-mode low power multirate XFP module—XFP10GER-192IR-L, V01

Cisco qualifies the optics that are approved for use with its PLIMs.

For the modules listed, use a single-mode optical fiber that has a modal-field diameter of 8.7 ±0.5 microns (nominal diameter is approximately 10/125 micron) to connect your router to a network.

Figure 1 shows the front panel of the 20-Port 10-GE XFP PLIMs.

Table 1 describes the PLIM LEDs for the 20-Port 10-GE XFP PLIM.

The 20-port 10-GE XFP PLIM power consumption—150 W (120 W with no optics installed, 30 W optics budget)

Caution

The 20-port 10-GE XFP PLIM can have all 20 ports filled with SR (1.5W) 10km XFPs. If you use optics other than SR, you must be careful not to exceed the power budget, which may result in some ports remaining unpowered. Cisco IOS XR software enables the ports in a sequence that allows the configuration to remain within the optics power budget. For more details on how the software controls PLIM power consumption, see Cisco IOS XR Interface and Hardware Component Command Reference for the Cisco CRS Router .

The 14-port 10-GE XFP PLIM supports from one to fourteen pluggable XFP optics modules.

The 14-port 10-GE PLIM has:

• Fourteen ports that accept XFP optics modules
• Status LED for the PLIM
• LED for each port

Note	For information about the XFP optical transceiver modules supported on the 14-port 10-GE XFP PLIM, see Cisco CRS Carrier Routing System Ethernet Physical Layer Interface Module Installation Note.

Note	The 14-port XFP PLIM has a fixed power budget for the pluggable XFP optics. See XFP Optics Power Management for detailed information.

The14-port 10-GE PLIM supports the following types of XFP optical transceiver modules:

• Single-mode low power multirate XFP module—XFP10GLR-192SR-L, V01
• Single-mode low power multirate XFP module—XFP10GER-192IR-L, V01

Cisco qualifies the optics that are approved for use with its PLIMs.

For the modules listed, use a single-mode optical fiber that has a modal-field diameter of 8.7 ±0.5 microns (nominal diameter is approximately 10/125 micron) to connect your router to a network.

Figure 1 shows the front panel of the 14-Port 10-GE XFP PLIMs.

Table 1 describes the PLIM LEDs for the 14-Port 10-GE XFP PLIM.

The 14-port 10-GE XFP PLIM power consumption—150 W (115 W with no optics installed, 35 W optics budget)

Caution

The 14-port 10-GE XFP PLIM can have all 14 ports filled with a combination of SR (1.5W) 10km XFPs and LR (2.5W) 40km XFPs. If you use optics other than SR or LR, you must be careful not to exceed the power budget, which may result in some ports remaining unpowered. Cisco IOS XR software enables the ports in a sequence that allows the configuration to remain within the optics power budget. For more details on how the software controls PLIM power consumption, see Cisco IOS XR Interface and Hardware Component Command Reference for the Cisco CRS Router .

Note	The 14-port XFP PLIM has a fixed power budget for the pluggable XFP optics. See XFP Optics Power Management for detailed information.

The 20- and 14-port XFP PLIMs have a fixed power budget for the pluggable XFP optics. The XFP pluggable optics for the 20- and 14-port XFP PLIMs have different power consumptions based on their reach and type. The number of XFPs which will power up in a PLIM depends on their aggregate power consumption within the allocated power budget.

During XFP insertion, the power is allotted to the optics based on the insertion order of the XFPs. On boot up and reload, priority is re-assigned to the lower numbered ports.

The recommended insertion sequence is to alternate between inserting XFPs in lowest numbered ports for each interface device driver ASIC to avoid oversubscription. The insertion order for a 20 Port PLIM would be “0,10,1,11,2,12,...9,19.” For a 14 Port PLIM, insertion order would be “0,7,1,8,...6,13.”

If the PLIM power budget is exceeded, a console log message is displayed informing the user the power budget has been exceeded and to remove the XFP:

plim_[x]ge: %L2-PLIM-6-NO_POWER_XFP : Port <port number>, Not enough power available 
to power XFP, powering off

Any unpowered XFPs should be removed to ensure that the same XFPs that were powered before a reload are the same XFPs that are powered after a reload. Removing the unpowered XFPs prevents the powered down XFPs being given priority after the reload.

A show command is provided to indicate how much of the XFP power budget is currently used and how much power an XFP is consuming:

show controllers tenGigE 0/3/0/0 internal

A PLIM impedance carrier must be installed in each empty PLIM slot in the Cisco CRS-1 chassis (Figure 1). The CRS 8-slot chassis is shipped with impedance carriers installed in the empty slots. The impedance carrier preserves the integrity of the chassis and is required for EMI compliance and proper cooling in the chassis.