Pack your data: Traveling Through a Network

I use Ping when I can’t connect to a server to test if the website is having connectivity issues. It is a quick and easy way to tell you if the destination server is off-line. Ping doesn’t capture device information as packets are routed through network devices but instead gives the amount of time it takes for the packet to be received and acknowledged. It also gives the failure rate of any dropped packets.

Traceroute is a good command to use when troubleshooting a failure in a connection. Network administrators use this command often when adding a new router or changing firewall configuration to trace packets through the system. If there is a failure, the trace information will pinpoint the IP of the device where it failed.

Data Packets

Data packets contain data along with headers information that include destination IP, data size, and other information the destination uses to consume the data. Once a packet is received, the receiving server sends an acknowledgement (called an ACK) to the sending system. The sending system knows all is good if an ACK is received and will continue to send data packets. When the sending system doesn’t receive a message back it indicates there wasn’t a successful connection. If a connection was established but there is a problem with corrupt data or dropped packets, the receiving server will respond with a NAK. This message traffic can be used when troubleshooting more complex communications issues.

Using Commands Ping and Tracert

I chose Omlet.co.uk and Chickens.fr to perform my network commands, the screen shots show results below. 

Ping

Using the ping command, both websites looked like typical working websites. Both servers responded fairly quickly, and all data was received without errors. 

Tracert

The tracert command showed a different story where: 

• Omlet.co.uk had three failed attempts, no timeouts and 20 hops with an average of 156 ms. 
• Chickens.fr had 12 failed attempts, 4 timeouts and 14 hops with an average of 169 ms.  

The tracert results paints a better picture of connectivity and network speeds.