Alcatel Carrier Internetworking Solutions 8800 User Manual
Roma
page -22
OmniSwitch Troubleshooting Guide
September 2005
Roma
Each Fabric Module is based on two Roma ASICs, which provide the store-and-forward switching fabric
function for the OS-8800 product. The Roma ASIC is bit-sliced; a group of eight Roma ASICs operates
together as a single synchronized fabric. A total of four Fabric modules are required to build a complete
Fabric in the OS-8800 system. An optional fifth Fabric Module may be used for fabric redundancy. In a
group of eight Roma ASICs, there is always one master and seven slaves. These ROMA ASICs are located
on Switch Fabric Modules at the rear of the chassis.
function for the OS-8800 product. The Roma ASIC is bit-sliced; a group of eight Roma ASICs operates
together as a single synchronized fabric. A total of four Fabric modules are required to build a complete
Fabric in the OS-8800 system. An optional fifth Fabric Module may be used for fabric redundancy. In a
group of eight Roma ASICs, there is always one master and seven slaves. These ROMA ASICs are located
on Switch Fabric Modules at the rear of the chassis.
The SFM module consists of two identical fabric slices. Each fabric slice consists of one Roma ASIC.
There is also a bridge FPGA that interfaces the on-board ASICs to the CMM modules through the BBUS
management bus. Major SFM elements are the following:
There is also a bridge FPGA that interfaces the on-board ASICs to the CMM modules through the BBUS
management bus. Major SFM elements are the following:
• Two Roma ASICs
• One Bbus FPGA
• One DC-DC Converter
• Reset Circuitry
• Clock Circuitry
• Power Fail Detect/ Uncontrolled Power Failure Circuitry
Following is the fabric hardware environment:
• The Roma-based fabric always operates using a set of eight Roma ASICs
• The eight operational Roma chips must be numbered according to bit slice position
• An additional two hot-standby Roma ASICs can provide for fabric redundancy
• Two Roma ASICs per separately insertable card, five fabric slots per Eagle chassis
• 64 fabric ports per Roma ASIC (supports up 64 Coronado ASICs or 16 Calais ASICs)
• Support for any architecturally coherent combination of Coronado and Calais ASICs
• 512 logical ports per system corresponding to Roma queues (maximum)
• 384 physical ports per system corresponding to Roma unicast queues (maximum)
• 64 IPC queues per system (maximum)
• 64 multicast FIFOs per system (maximum)
• 24 physical ports per NI slot (maximum)
• Calendar mechanism for dequeuing unicast and multicast frames
• Multicast (VLAN) vector table for multicast propagation control
• Greater than 500 MHz raw link rate per fabric port (each direction)
• 2.4 Gbps per Coronado
• 10 Gbps per Calais (or equivalent replacement hardware)
• Four paycheck levels to support flow prioritization