Netopia R910, Руководство пользователя

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14-158 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 R910 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 on the
previous page). 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.
In the Statistics & Diagnostics screen, select Trace Route and press Return. The Trace Route screen appears.
To trace a route, follow these steps:
1. Select Host Name or IP Address and enter the name or address of the destination you want to trace.
2. Select Maximum Hops to set the maximum number of routers to count between the Netopia Router and
the destination router, up to the maximum of 64. The default is 30 hops.
3. Select Timeout (seconds) to set when the trace will timeout for each hop, up to 10 seconds. The default is
3 seconds.
Trace Route
Host Name or IP Address:
Maximum Hops: 30
Timeout (seconds): 5
Use Reverse DNS: Yes
START TRACE ROUTE
Enter the IP Address/Domain Name of a host.
Trace route to a network host.