Tracert Test - Planet Networking & Communication VGW 20FS Series User Manual

Tracert Test

3.14.5
Tracert is a trace router used to track routing.
Tracert sends a sequence of Internet Control Message Protocol (ICMP) echo request packets
addressed to a destination host. Determining the intermediate routers traversed involves adjusting the
time-to-live (TTL), aka hop limit, Internet Protocol parameter. Frequently starting with a value like 128
(Windows) or 64 (Linux), routers decrement this and discard a packet when the TTL value has reached
zero, returning the ICMP error message ICMP Time Exceeded.
Tracert works by increasing the TTL value of each successive set of packets sent. The first set of
packets sent have a hop limit value of 1, expecting that they are not forwarded by the first router. The
next set have a hop limit value of 2, so that the second router will send the error reply. This continues
until the destination host receives the packets and returns an ICMP Echo Reply message.
Trace route uses the returned ICMP messages to produce a list of hops (which usually consists of
routers and layer 3 switches) that the packets have traversed. The timestamp values returned for each
router along the path are the delay (aka latency) values, typically measured in milliseconds for each
packet.
Tracert introduce：
Click ' Tracert Test' in the navigation tree;
Fill in IP address or domain whose route needs to be tracked, and then click start.
Figure 3.16-7 Ping Test
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4-/8-/16-/24-/32-Port SIP Internet Telephony Gateway