What Is Packet Loss And How Does It Affect Your Network?

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This is part 1 of a 3-part series on that ever-so frustrating issue of packet loss. Parts 2 and 3 will follow shortly. 

What is packet loss? 

In this series of articles, we are going to educate you on what packet loss is, how to measure it and how to make it go away. Simply put, packet loss is when “one or more packets fail to make their destination” and in many cases, it is a minor background issue. Many applications are designed to be tolerant of packet loss by having a level of acceptable packet loss or relying on TCP’s built in retransmission. 

What is high packet loss

Acceptable packet loss? 

While it sounds like an oxymoron as packet-loss should not be acceptable, many application/protocol designers are aware that packet loss happens and as such, protocols are designed to tolerate it. For example, you could probably lose 1% of all the packets involved in a SIP VoIP call and have no issues. 

What causes packet loss?

One of the most common causes of packet loss is congestion, the act of having a link close to its maximum throughput that can often cause packets to start getting dropped. Other causes tend to include faulty hardware, general radio based issues and in some cases, packets can be dropped intentionally by devices to achieve a purpose such as limiting traffic throughput or for routing purposes. 

What are the affects of packet loss?

Packet loss will generally reduce the speed or throughput of a given connection. Sometimes this can result in a loss or reduction in quality to latency sensitive protocols or applications such as streaming video or voice over IP, where there is less of a requirement for accuracy. Packet loss will still have some minor knock on affects since it may increase the CPU load to process the additional network overhead. 

In the next article, I will cover how to identify packet loss on simple networks and on routed networks.