Spirent SmartBits System, Справочное руководство

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Chapter 13: Token Ring Cards
Token Ring Operational Detail
182 SmartBits System Reference
Counters that originate from MAC reports to LAN Manager Server Functional addresses
(usually REM frames) are listed below. We should expect to receive multiple error counts
for
non-isolating errors when there is more than one other station on the ring
.
Card Triggers
The TR Smartcard has two trigger comparators that can be specified to match patterns of 1
to 6 bytes in length anywhere in a frame. The trigger offset is specified from the Access
Control byte.
The trigger comparator is normally used on the ring (receive) data but it can be switched to
trip on the transmitted data. This facility is only used by the latency measuring part of the
Smartwindows application.
The receive trigger comparators can be set to trigger on AC byte patterns. The trigger
counter will only increment when the trigger is associated with a frame so although the
trigger will trip with a token pattern (that is, the Trigger indicator LED will flash) its
counter will only increment if the trigger pattern specifies a frame.
Controlling Connections to the Ring
The default operation of this card is to silently connect to the ring on startup. The card is
not programmed to perform the lobe tests, duplicate address tests and other MAC
exchanges on startup as it is not intended to act as a ring station.
Although this process is sufficient for most applications envisaged for the card, users may
need finer control for their tests. The TR card has provision to control the operation of the
card through the
TRA serial command and its corresponding TRAdvancedControl function
in the programming library.
Counter Size Counts
Line Errors 16 Line Errors detected by other units (isolating).
Internal Errors 16 Recoverable internal errors on other units.
Burst Error 16 Burst Errors detected by other units (isolating).
A/C Error 16 Monitor violation detected by AMP (isolating).
Abort Delimiter 16 Abort Delimiter transmitted.
Lost Frame 16 Incompletely stripped frame (non-isolating).
Receiver
Congestion 16 Unit overloaded (non-isolating).
Frame Copied 16 Possible duplicate MAC address (non-isolating).
Frequency Error 16 Excessive jitter detected by Active Monitor (non-isolating).
Token Error 16 Circulating frame or reserved token (non-isolating).