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IM AQ1300-01EN
Features
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App
Index
1.9 Emulation
IPv4 Host
ARP Reply
To perform address resolution, the AQ1300/AQ1301 sends an ARP reply when it receives an ARP
request.
When you enable ARP replying, it is always enabled regardless of the test mode setting, filter
condition, or measurement or transmission condition.
When Auto or Auto(Remote) has been selected in the Test menu, ARP replying is always enabled and
set to “Source Address only.”
When Manual has been selected in the Test menu and the test layer is L3-IPv4, you can configure
ARP replying using the emulation settings.
ARP Requests That Are Not Answered
The AQ1300/AQ1301 will not send an ARP reply in response to the following kinds of ARP requests.
• ARP requests with a LLC/SNAP header attached (only ARP requests that conform to the DIX
specification are supported)
• ARP requests with an MPLS label attached
• ARP requests that are counted as errors, except for payload and sequence errors
• ARP requests that are received at the same time that a linkdown occurs
• ARP requests that are received at the same time that a collision occurs
• ARP requests whose packet lengths are less than 63 bytes, greater than 1519 bytes (greater
than 1523 when there is one VLAN stack or greater than 1527 when there are two VLAN stacks),
or greater than the oversize threshold.
• ARP requests with three or more VLAN stacks.
VLAN Tag Handling
The AQ1300/AQ1301 sends ARP replies in response to ARP requests with VLAN tags attached.
ARP Requests with Test Tags
The AQ1300/AQ1301 sends ARP replies in response to ARP requests with test tags attached.
ARP Reply Transmission Conditions
• If a collision occurs while an ARP reply is being sent, it is resent.
• If an ARP request is received while transmission is paused, an ARP reply is sent after
transmission is resumed.
• If transmission is paused and the AQ1300/AQ1301 is waiting to send an ARP reply and a normal
test frame, after transmission resumes, the AQ1300/AQ1301 will send the ARP reply first and
then the normal test frame.
• Replies are not sent for ARP requests that are received before the transmission of the current
ARP reply has finished.
• If a linkdown occurs immediately after an ARP request is received, the AQ1300/AQ1301 will not
send a reply to that request.
Ping Reply
The AQ1300/AQ1301 sends a ping reply when it receives a ping request.
When you enable ping replying and the test mode is not Loopback Test, ping replying is always
enabled regardless of the test mode setting, filter condition, or measurement or transmission condition.
When Auto or Auto(Remote) has been selected in the Test menu, ping replying is always enabled.
When Manual has been selected in the Test menu and the test layer is L3-IPv4, you can configure ping
replying by specifying the emulation settings.
