Cabletron Systems SmartSwitch 6000 User Manual page 165

Host MAC Address
Session Type
T1
Configuring SNA
is the MAC address of the host or workstation to which an SNA/LLC2 device needs
to connect. If the host will be attached via an Ethernet interface in the FRX/FRM, this
address must be entered as a "bit-swapped" translation of the address that the node is
expecting. Bit swapping is done by reversing the order of the bits (digits) within each
byte (pair of digits) of the hexadecimal address, while leaving the sequence of the
bytes unchanged.
For example, to bit-swap the hex address
1. Break the address into pairs of digits:|
2. Reverse the digits within each pair: |
3. Replace each digit as specified in the following table. This reverses the binary bits
of each digit. For example,
Digit Convert to
0 0
1 8
2 4
3 C
Using the example,
converts to:
| 02 | 00 | 08 | 00 | 08 | 11 |
4. Enter the bit swapped value (e.g.,
value will arrive at the host as the proper address (e.g.,
translated.
if Originated, means the FRX/FRM will initiate LLC2 sessions from the configured
Host MAC Address. If Terminated, the node will accept LLC2 sessions destined for
the host address.
In the examples shown in Figure 8-4 (on page 8-18), LLC2 hosts must be configured
in the FRX/FRM databases as follows:
Example 1: One record in FRX/FRM 2 for the host, with
.
Terminated
Example 2: One record in FRX/FRM 1 for the host, with
, one record in FRX/FRM 2 for the host, with
nated
Example 3: Two records in the FRX/FRM for the host, one with
, the other
Originated
Example 4: One record in the FRX/FRM for the host, with
.
Originated
is the Reply Timer, which is used by the local node to detect a failure by the remote
station to send a required acknowledgment or response. The local node will start the
timer when it transmits one of these:
an Information LPDU (LLC protocol data unit).
a Command LPDU with the P bit set to
is already running, the local node will reset and restart it.)
400010001088
40 | 00 | 10 | 00 | 10 | 88 |
04 | 00 | 01 | 00 | 01 | 88 |
( binary) becomes
7 0111
Digit Convert to
4 2
5 A
6 6
7 E
| 04 | 00 | 01 | 00 | 01 | 88 |
020008000811
.
Terminated
B'1.'
:
( binary).
E 1110
Digit Convert to Digit Convert to
8 1 C
9 9 D
A 5 E
B D F
) as the Host MAC Address. This
400010001088
Session Type
Session Type
Session Type
Session Type
Session Type
(If this LPDU is sent while the timer
3
B
7
F
) after being
=
=
Origi-
= .
Terminated
=
=
8-23