Cabletron Systems 9F310-02 User Manual

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DC/DC Converter
 
DC/DC Converter
 
The DC/DC converter converts the 48 VDC on the system power bus to the 
necessary operating voltages for its host network services module. The diagnostic 
controller monitors and controls the operation of the DC/DC converter.
 
INB Interface
 
Each module that attaches to the INB has an INB Network Interface Block (NIB). 
The INB NIB converts canonical frames to fixed length data blocks for 
transmission onto the INB. For data blocks received from the INB, the INB NIB 
reassembles the data blocks received from the INB back into canonical frames for 
transmission to the Fast Packet Switch (FPS) then from the FPS to the front panel 
ports. 
 
Fast Packet Switch 
 
The Fast Packet Switch (FPS) is a hardware based switch design that is the key 
building block of the MMAC-Plus. All filtering/forwarding decisions are made in 
hardware as opposed to software as in traditional bridges. This custom hardware 
allows the FPS to process over 150K frames per second. The FPS is designed to 
support up to 64 ports that are shared between the host processor, the INB 
backplane, and LAN/WAN interfaces on the front panel of MMAC-Plus 
modules. The FPS can operate in two modes; as a traditional bridge or as a 
SecureFast Packet Switch (SFPS). When operating in bridge mode, it makes 
filtering /forwarding decisions based on Destination Address (DA), with 
standard IEEE 802.1d learning. When operating in SFPS mode, all 
filtering/forwarding decisions are made based on a DA-SA pair and its receive 
port. These DA-SA pairs with the associated receive port are programmed into 
the switch using Cabletron’s Automated Connection Management System 
(ACMS). This provides the network administrator with the ultimate network 
security without the performance degradation found when using routers or 
bridges with special filtering capabilities. The MMAC-Plus hub can support 
modules operating in bridge mode and SFPS mode simultaneously providing 
security when/where needed and ease of configuration where security is not 
required. 
 
i960 Core
 
The i960 core provides the SNMP protocol stacks, to support industry standard 
MIBs. Additionally, Cabletron enterprise extension MIBs are supported for each 
media type. Advanced management services, such as the Distributed LAN 
Monitor, telnet and network address to MAC address mapping, are also provided 
by the i960 core.