User's Manual

Harmony Utility 33
• Last ACK RSSI: This statistic reports the RSSI (Received Signal Strength) for the
last acknowledgment (ACK) received by the PCI Card. RSSI is reported in decibels
(dB) and typically ranges from 0 to 75. In general, an RSSI less than 15 indicates a
weak signal and an RSSI greater than 30 indicates a strong signal.
• ACK Errors:
This statistic reports the number of unicast transmit attempts for
which no acknowledgement (ACK) was received.
• CTS Errors:
This statistic reports the number of Clear To Send (CTS) errors. When
the PCI Card uses RTS/CTS before transmitting a packet, it first sends a Request
to Send (RTS) message to the packet’s recipient. The packet’s recipient then
returns a CTS message to the PCI Card. When the PCI Card receives the CTS, it
sends the packet to the recipient. However, if the PCI Card does not receive a CTS
within a fixed period of time, it will resend the RTS. After a fixed number of
retries, the PCI Card will record a CTS Error if a CTS has not been received.
• Unicast Bytes Received:
This statistic reports the total number of bytes contained
in the unicast packets received by the PCI Card.
• Multicast Bytes Received: This statistic reports the total number of bytes con-
tained in the multicast packets received by the PCI Card.
• WEP Undecryptable:
This statistic displays the number of packets that were dis-
carded due to a problem during decryption, such as mismatched WEP Keys.
• Bad Frame Checksum: This statistic displays the number of received packets that
failed the CRC (Cyclic Redundancy Check) of the Frame Check Sequence (FCS).
• Last Frame’s RSSI:
This statistic reports the RSSI (Received Signal Strength) for
the last packet received by the PCI Card. RSSI is reported in decibels (dB) and
typically ranges from 0 to 75. In general, an RSSI less than 15 indicates a weak
signal and an RSSI greater than 30 indicates a strong signal.
• Duplicate Frames:
This statistic displays the number of duplicate packets
received by the PCI Card. When the PCI Card successfully receives a packet, it
sends an acknowledgment (ACK) to the transmitting node. If the ACK does not
reach the transmitting node within a specified period of time after it sent the
packet (due to interference or some other type of delay), it will resend the packet
to the recipient. In this case, the PCI Card then receives the packet a second
time, records that it received a duplicate packet, and sends an ACK again.