1-32
IM AQ1300-01EN
Ping Requests That Are Not Answered
The AQ1300/AQ1301 will not send a ping reply in response to the following kinds of ping requests.
• Ping requests with an LLC/SNAP header attached (only ping requests that conform to the DIX
specification are supported)
• Ping requests with an MPLS label attached
• Ping requests that are counted as errors, except for payload and sequence errors
• Ping requests that are received at the same time that a linkdown occurs
• Ping requests that are received at the same time that a collision occurs
• Ping requests whose packet lengths are less than 63 bytes, greater than 10000 bytes, or greater
than the oversize threshold.
• IP fragmented ping requests
• Ping requests with three or more VLAN stacks.
VLAN Tag Handling
The AQ1300/AQ1301 sends ping replies in response to ping requests with VLAN tags attached.
Ping Reply Transmission Conditions
• If a collision occurs while a ping reply is being sent, it is resent.
• If a ping request is received while transmission is paused, a ping reply is sent after transmission
is resumed.
• If transmission is paused and the AQ1300/AQ1301 is waiting to send a ping reply and a normal
test frame, after transmission resumes, the AQ1300/AQ1301 will send the ping reply first and
then the normal test frame.
• Replies are not sent for ping requests that are received before the transmission of the current
ping reply has finished.
• If a linkdown occurs immediately after a ping request is received, the AQ1300/AQ1301 will not
send a reply to that request.
Automatic MAC Address Acquisition
In automatic MAC address acquisition, the AQ1300/AQ1301 uses ARP processing to automatically
obtain the MAC address of the device under test (DUT) and then uses that address as the frame
destination MAC address.
Automatic MAC Address Acquisition Conditions
• When automatic acquisition is enabled, ARP acquisition is performed with the specified target
host (IP address) at the start of measurement. If the target host is not in the same segment as
the AQ1300/AQ1301, ARP acquisition is performed with the default gateway.
(Acquisition is performed before measurement starts. Afterwards, the statistics are cleared and
measurement starts.)
• The AQ1300/AQ1301 waits for a reply after it sends an ARP packet. The timeout value is 1
second. The AQ1300/AQ1301 will try again after timing out.
• The acquired MAC address is cleared at the start of the next test.
• If the MAC address increment feature is enabled, it has priority.
• If the variable field feature is enabled, it has priority.
Ignored ARP Replies
The following ARP replies are not recognized as ARP replies when they are received.
• ARP replies with an LLC/SNAP header attached (only ARP replies that conform to the DIX
specification are supported)
• ARP replies with an MPLS label attached
• ARP replies that are counted as errors, except for payload and sequence errors
• ARP replies that are received at the same time that a linkdown occurs
1.9 Emulation