Cabletron Systems NBR-420 User Manual
Page 12
 
Chapter 1:
Introduction
Page 1-4
NBR-SERIES Installation Guide
Bridging/Routing
The NBR-420 and NBR-620 can support two optional Bridge/Router 
Interface Modules (BRIMs). These modules allow for additional Ethernet 
connections, Wide Area (Full or Fractional T1; 56k DDS) access, or links 
to existing high-speed network backbones such as Asynchronous Transfer 
Mode (ATM) or Fiber Distributed Data Interface (FDDI).
Memory
The NBR comes with 4 Megabytes (MB) of Shared Dynamic Random 
Access Memory (SDRAM), 8 MB of Local Dynamic Random Access 
Memory (LDRAM), and 2 MB of FLASH Electrically Erasable 
Programmable Read Only Memory (FLASH EEPROM). In addition, the 
NBR motherboard provides the option of upgrading memory capacity by 
using Single In-line Memory Modules (SIMMs). 
In order to fully use Remote Monitoring (RMON), it is necessary to 
upgrade local memory with an 8 MB SIMM. Without this upgrade, some 
RMON groups may not be available.
DLM
The NBR allows the option of using Cabletron Systems Distributed LAN 
Monitor (DLM) software to locally poll and monitor any Simple Network 
Management Protocol (SNMP) or Internet Protocol (IP) device.
Management Information Base (MIB) Support
The NBR provides IETF MIB support, which includes the following:
•
Cabletron Systems Enterprise MIBs
•
Remote Monitoring MIB (RMON)
•
Bridge MIB
•
MIBII
NOTE
For information on how to order SIMM upgrade packages, 
contact Cabletron Systems Technical Support.