Where do "lost" packets go?

[vaconcamp]

I pinged my university's private server just to see what would happen (I'm really bored) and all 4 packets that I sent were never received. I assume this was because they block out any foreign incoming connections, but it got me thinking. Where did those packets go? What is the thing that gets rid of those foreign incoming packets once they're rejected? I know bus topology networks have terminators, but is this also true for other topologies?

 

[maxwellmelon]

they just disappear. lost packets could have been received and as you say there security just ignores them as bad. or the data never made it to the server u pinged. basically they go to the point that a router broadcast it and no computer picks them up. (when you send a ping its amazing the number of devices that see it but of course if its not meant for them they just ignore it.

 

[vaconcamp]

they just disappear. lost packets could have been received and as you say there security just ignores them as bad. or the data never made it to the server u pinged. basically they go to the point that a router broadcast it and no computer picks them up. (when you send a ping its amazing the number of devices that see it but of course if its not meant for them they just ignore it.

I know they disappear, but I meant physically where do they go? Like where do electrical impulses that make up that packet go? That's why I was wondering if there was a terminator somewhere that just constantly receives rejected packets.

 

[bill001g]

They go the same place good packets go. Its not like the end device somehow puts them in a pile or something. They are just number in memory and they are overwritten.

All a bad packet is one that the mathematically check sum included in the packet does not match the checksum done when the packet is received. If a packet is considered bad the receiving device in effect pretends it never received it

 

[sg4rb0]

I pinged my university's private server just to see what would happen (I'm really bored) and all 4 packets that I sent were never received. I assume this was because they block out any foreign incoming connections, but it got me thinking. Where did those packets go? What is the thing that gets rid of those foreign incoming packets once they're rejected? I know bus topology networks have terminators, but is this also true for other topologies?

The term lost is used to describe that when you sent an icmp echo to say 192.168.1.1, you did not receive an echo reply back. Therefore as far as your computer is concerned it's "lost". Usually what happens is when you sent an ICMP echo to a particular destination, it will hit a router or firewall that will have an access control list on it. The control list will filter out icmp echo type requests and just release it from the input buffer queue. Therefore you never receive a reply because the packet never reached the final destination. If, however, it did reach the destination, you would get an icmp echo reply to tell you the packet was sent and received successfully.