Bridging

There are two bit-order options:

¥LSBÑLeast SigniÞcant Bit

¥MSBÑMost SigniÞcant Bit To set the bit order:

1.Click on the empty LSB or MSB option button. When the option button is filled (), the selected bit order is enabled.

NOTE

Novell recommends setting the bit order to LSB (Least SigniÞcant Bit) when bridging between Token Ring and Ethernet. When the bridge is set to operate in LSB mode, all the NIC cards on the Token Ring network should also be conÞgured to operate in LSB mode.

The IBM Translation Table

The IBM Translation Table allows you to conÞgure the mode of frame translation for IBM SNA frames bridged from a Token Ring network to an Ethernet network. The device will translate IBM SNA frames using any of the Þve default SAP Service Access Point) addresses to Ethernet Type-II frames with a type code of 80D5; these default SAP addresses are shown in the IBM Format Table as the Þrst Þve entries.

Figure 2-35. The IBM Format Table

If the state on the entry is enabled, then the translation for the Token Ring frame with the given SAP address will be translated to Ethernet Type-II frame format.

If the state of the entry is disabled, the frame will be bridged as a 802.2 frame maintaining the SAP address information.

From the IBM Translation window you can change the Þrst Þve default SAP address entries, or add up to 15 additional entries to the table for the purpose of translating IBM SNA frames.

To view all the entries in the table you must click on the scroll box to the right of the displayed entry. A small scrollable window will appear. You can scroll through the window to view all the entries.

2-94

Setting Bridge Translation

Page 112
Image 112
Cabletron Systems 2.2 manual IBM Translation Table