DATA-LINC GROUP
6
PN 161-09990-002C
rev 3/29/04
SRM6200E-SLC User’s Guide
Configuration
In most cases, the SRM6200E-SLC comes pre-configured from the factory. However, it may sometimes be necessary to
change the configuration. Most parameters are changed in the radio section of the modem although there are a few settings
that are set using switches. If you are not sure if you need to change the configuration of the SRM6200E-SLC, you probably
don’t. Please contact Data-Linc Group for further information if you are unsure about your configuration.
Switch Settings
To access the switches, remove the modem from the SLC Rack. The switch bank (SW1-Diagram 3, pg. 24) is located in the
center of the large PCB.
Note: Leave switch positions 4, 5 and 6 at factory setting of off unless otherwise directed by Data-Linc Group.
Changing these switches requires a radio parameters change.
MAC Filtering Function
All devices capable of generating Ethernet traffic have a MAC (Medium Access Control) address. This address is used in the
communications of Ethernet data.
The SRM6200E-SLC is factory set to perform MAC level filtering. This means that it learns all the MAC addresses from the
LAN it is connected to, and only forwards data packets across the radio links which are destined for addresses located
across the radio link. The MAC filtering function is enabled by setting switch (SW2-Diagram 3, pg.24) to the on position.
The MAC address table can store up to 10,000 addresses. Each entry to the table has a lifetime of six minutes after which
the address is deleted. This dynamic table building allows for the possibility of stations being removed from the LAN. The net
result of this filtering functionality is the reduction of unnecessary network traffic across the radio link.
Note: Many Ethernet networks have data packets that are not covered by the MAC filter function (broadcast packets
for example). These packets can occupy tremendous amount of the network’s bandwidth and overwhelm the
SRM6200E-SLC section of the network. If the SRM6200E-SLC’s are going to be installed where they are linked to
an open network (on office network, etc.), a properly configured router or switch should be installed to protect the
modems from excessive data traffic. If you are unsure about your network, please consult with your network
administrator.
