Netopia R2121, Руководство пользователя

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15-4 User’s Reference Guide
Packets Lost: The number of packets unaccounted for, shown in total and as a percentage of total packets
sent. This statistic may be updated during the Ping test, and may not be accurate until after the test is over.
However, if an escalating one-to-one correspondence is seen between
Packets Out and Packets Lost , and
Packets In is noticeably lagging behind Packets Out , the destination is probably unreachable. In this case, use
STOP PING .
Round Trip Time (Min/Max/Avg): Statistics showing the minimum, maximum, and average number of
seconds elapsing between the time each Ping packet was sent and the time its corresponding return Ping
packet was received.
The time-to-live (TTL) value for each Ping packet sent by the Netopia R2121 is 255, the maximum allowed. The
TTL value defines the number of IP routers that the packet can traverse. Ping packets that reach their TTL value
are dropped, and a “destination unreachable” notification is returned to the sender (see the table above). This
ensures that no infinite routing loops occur. The TTL value can be set and retrieved using the SNMP MIB-II ip
group’s ipDefaultTTL object.
Trace Route
You can count the number of routers between your Netopia Router and a given destination with the Trace Route
utility.
Select Trace Route in the Statistics & Diagnostics screen and press Return to go to the Trace Route screen.
Netopia
Netopia
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host
Netopia
Netopia
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Netopia
Netopia
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host
host
send Ping packet 1
send return Ping packet 1
send Ping packet 2
send Ping packet 3
send return Ping packet 2
send return Ping packet 3
receive return Ping packet 1
receive Ping packet 1
receive Ping packet 3
receive Ping packet 2
receive return Ping packet 2
receive return Ping packet 3
time