significance of tracert

[ashwinssource]

I tried tracert on the same public IP three times and I get three different outputs. In the first one, I get 16 request timed outs and then the 17th entry which completes the route successfully. In the second set, I get first 4 request-timed outs followed by a few entries that complete the route. The third time, I get a 15 full entries that show the real route.

Now, my question is, if an application is tries to access the target IP, what significance does the above have ? Is it that the app does not work first time, and works from second time or third time ?

[Paul Komski]

15 full entries that show the real route
"The Real Route" is the route from your PC to the other one and there is no guarantee that two successive packets will travel the same route. Even two packets from the same file may travel a different route. That is an essential way that the internet works since if there is a "blockage" or "bottleneck" the servers will keep redirecting the packets on their travels. Some will never reach their destination and will "time out" others that haven't got there (no acknowledgement received) will be resent by your PC.

[ITgonna_be]

Routers allow for the quickest or the most available path to the intended destination. It could be slightly different at ANY time, depending upon time of day, local or regional Internet traffic, current events (locally, regionally or nationally), power outages or interruptions, systemic changes of any kind.

Pinging (or trace-routing) my ISP here in Eugene, Oregon means a path south thru the SFO Bay Area, or to Seattle and back, or whatever. Depending upon traffic loads and where my ISP has THEIR service accounts. I've seen it change occasionally.

[juniper]

with trace you only get the route the packet took to get to the host not the path back ( some extended traces you can ). the internet is asyncronous meening the packets can take multiple paths, trace sends 3 ICMP packets to each hop. trace is often blocked by firewalls it uses ICMP "time exceeded" responses to trace the path which is different from ECHO REQUESTS and ECHO REPLIES that are used by ping and can be blocked seperatley. Also alot of ISPs are using MPLS which is a tunneling protocol used mostly for traffic enginering and speed since the routers are basicly switching and not looking up routes in the routing table which makes them faster, the point of me bringing MPLS in this is because MPLS will not decrament TTLs ( you can make it decrament TTLs with a certain command but is almost always shut off to hide routes) so you will not see the routers when going through an MPLS tunnel with trace.