Packet loss is defined as the failure of one or more transmitted packets to arrive at their destination. While every network can expect to encounter some packet loss from time to time, significant or sustained packet loss does require investigation into the root cause.
5 Reasons for Packet Loss
Link Congestion
Networking devices drop packets when congestion in the network occurs, as there are more packets trying to traverse the link than it is designed to handle.
Overutilized Devices
Similar to link congestion, when a device tries to process more traffic at any given moment than it is designed to, the device can drop the excess packets it can’t process.
Faulty Hardware
Damaged network cards, deteriorated ports, bad routers, and bad wiring can all lead to some packet loss within a network.
Wireless Networks
Wireless networks are more prone to packet loss as they often deal with interference from other networks in the area, physical structures, distance, etc.
Configuration Errors
Whenever configurations must be made, human error must be taken into consideration. Was the network designed, laid out, and configured correctly, with the appropriate cables and devices? If different speed/media cables are mixed, or a device is configured for full-duplex traffic instead of half-duplex traffic, then packet loss is to be expected.
Effects of Packet Loss
Depending on the application, it can be fairly easy to spot the signs of packet loss. VoIP, video, and streaming services are some of the easiest applications to identify packet loss, as they cause noticeable errors in the user experience of the streaming service. Voice and/or video may be delayed or cut out all together.
Not being able to hear the person you’re talking to over the phone or having part of your live sporting event not show up in real time can be frustrating, but what about when the packet loss occurs at a network link that’s connected to an important security or monitoring tool, like a next-gen firewall or network analyzer
Significant packet loss can render your tools useless. Without seeing all of the puzzle, your tools won't be able to properly diagnose network problems or security vulnerabilities. People like to use the analogy of a puzzle missing pieces, but that doesn't convey the seriousness of packet loss as it pertains to security tools. It's closer to dark spots on medical imagery. Would you accept a diagnosis from a doctor who was pretty sure they saw most of the data he or she needed? You'd want all of the information available in order to give an accurate reading.
Rather than relying on SPAN ports as your access method in your network, designing your network using a combination of network test access points (TAPs) and purpose-built packet brokers can ensure that your security and monitoring tools receive all 100% of the traffic, with no dropped packets.
[Want to learn more? Download our TAP vs SPAN whitepaper today to understand the best way to ensure 100% access to all network traffic.]