Packet Loss Test

Before it’s sent, data is packaged into several layers. This data packet then travels through various hubs (fiber optics, copper cables, wireless, etc.) to reach its destination. As it travels through these hubs, data packets can get lost or delayed. This results in packets arriving late or never arriving, causing network performance to suffer. 

One of the areas where the effects of packet loss are most apparent are in VoIP (voice over internet protocol) calls. When you look at voice calls conducted over an internet connection—whether through Google Voice, WhatsApp, Skype, Facebook voice chat, or other platforms—you can immediately recognize the effects of packet loss, which are typically manifested as the call “breaking up” or “lagging.” The quality of the call becomes poor and you start to miss words or even whole sentences. This may be because the data got lost along the way. These same audio effects can occur in video calls, including those over FaceTime, Zoom, and Skype.

Used to identify the cause of data arriving late or failing to reach the intended destination on a network, a network packet loss test can help you address the cause to keep your overall environment healthy and improve performance. Packet loss can be a major issue in networks of any size.

You can use a packet loss checker to perform two types of packet loss tests:

1. Packet loss caused by network congestion
2. Packet loss caused by wireless signal coverage

Though packet loss can be a common cause for poor network performance, these issues can also be caused by general bandwidth problems, delay, and jitter. To help pinpoint whether packet loss is behind your poor network performance, a packet loss tester is designed to monitor key elements of the network in addition to packet loss itself. This helps you more easily determine if the network performance issues are due to data transmission or congestion.

Packet loss is responsible for many network problems capable of impacting performance. The purpose of packet loss testing is to get to the bottom of those network problems by determining whether packet loss is responsible for low-quality VoIP connections or general network connectivity issues. If so, the tests can help you determine what’s causing the packet loss, so you can attempt to resolve the issue and improve your network performance. 

Unsuccessful data packets can slow down your network speeds, throw off your network bandwidth and throughput, and cause bottlenecks. Packet loss can also quickly become expensive if you don’t address its root cause, since it may cause you to spend money on more bandwidth and extra IT infrastructure to compensate for the lag. 

VoIP packet loss tests are also important for preventing low voice or video quality on calls to improve overall performance. Using network packet loss test tools like SolarWinds^® VoIP & Network Quality Manager (VNQM) can help you better control network latency, distortion, and noise by monitoring key performance metrics such as packet loss, network latency, jitter, and MOS. Effectively monitoring packet loss can lead to better network performance and fewer issues with VoIP.

While many tools are available to test packet loss for you, the general process follows the TCP/IP communication model. TCP stands for Transmission Control Protocol, and IP stands for Internet Protocol. Together, they find IP addresses to send data to (via IP) and ensure accurate delivery to the correct address (via TCP).

Windows and OS computers have native features that allow you to manually conduct a network packet loss test using TCP/IP for a specific IP address. These protocols send a series of data test packets to a certain device while tracking how many pings the device returns as it receives a packet. TCP/IP then detects the discrepancy between the number of packets sent and the number of packets received and calculates it as a percentage. For example, if only 12 out of 48 total packets were received, that communication line suffered a 75% data loss.

Starting a packet loss test on a Windows interface is simple: go to the Command Prompt application, enter the command ping -n 100 1.1.1.1, and wait for the results. Note that you can change the number of tests conducted using the -n XXX field (e.g. -n 75 for 75 tests, -n 32 for 32 tests, etc.). For MacOS, go to the Terminal application, input ping 1.1.1.1, press the return button, and watch it automatically run tests. To stop the program, press Control + C.

SolarWinds VNQM is designed to offer deep, critical call quality of service (QoS) metrics and WAN performance insights. The software is built to help you maintain and improve network conditions for successful VoIP delivery. 

VNQM comes with real-time WAN monitoring and site-to-site WAN performance alerts. It can also identify VoIP performance problems using call detail record (CDR) analysis. Additionally, VNQM can communicate with a variety of different systems—including Cisco systems—for a more comprehensive monitoring experience. 

VNQM offers powerful, advanced packet loss testing and monitoring capabilities designed to help you track key VoIP call performance metrics. This allows you to quickly and easily pinpoint the cause of poor call quality. The tool also lets you quantify packet loss performance for emulated VoIP traffic, which means you can create VoIP deployment performance baselines for comparison with future performance metrics. 

VNQM comes with a powerful and intuitive dashboard built to help you get a better handle on VoIP monitoring across your full network. In addition to packet loss, VoIP & Network Quality Manager lets you monitor network latency and jitter to help you improve network performance across your environment. 

The results of a packet loss test can provide valuable insight into the health of a network. Packet loss can happen for various reasons, such as congestion on the network, faulty hardware, or software issues.

Any percentage of packet loss is less than ideal. If you receive a packet loss rate between 2-5%, that means your network has an underlying problem that can cause greater disruption in the near future. However, if the packet loss rate is higher, it can indicate that the network is experiencing congestion, which means that too much data is being transmitted over the network at once. This can cause delays and affect network performance.

Hardware issues can also cause packet loss. For example, if there is a faulty router, damaged wire, or malfunctioning switch in the network, they may drop packets or fail to transmit them properly. In some cases, software issues such as bugs or misconfigured settings can also lead to packet loss.

Addressing packet loss is essential for maintaining a healthy and reliable network. If congestion is causing packet loss, it may be necessary to upgrade the network's bandwidth or optimize its configuration to reduce the amount of data transmitted. If hardware issues are causing packet loss, defective equipment may need to be replaced or repaired. Additionally, network administrators may need to review the network's software configurations and perform troubleshooting to identify and resolve any software issues.

In addition to deploying network packet loss tests to locate data transmission errors, SolarWinds VoIP and Network Quality Manager is capable of measuring other valuable metrics, including:

• Latency: This metric is a measure of the time it takes for a data packet to reach its final destination. In video and voice calls, latency manifests in audio and visual delays; on websites, it can cause web pages to run slower, reducing the quality of users’ online experiences. To calculate latency, VNQM tests a data packet using four timestamps that measure round trip time, source-to-target time, target processing time, and target-to-source time.
• Jitter: This metric gives insight into latency changes that cause inconsistent data synchronization. Jitter often distorts visual and audio calls and, if severe, can make communication unintelligible. Network Service Assurance operations in VNQM use configurable settings to help users locate problem points stemming from considerable jitter. Specifically, VNQM issues a set number of packets of a certain size and interval pattern at a customized frequency.
• Mean Opinion Score (MOS): VNQM generates MOS to provide an overarching score of your network’s health and call quality from the user's perspective. VNQM rates your network on a scale of 1 to 5 using an International Telecommunications Union (ITU) algorithm, along with other metrics like latency, jitter, and packet loss. A score of 5 reflects superior user-friendliness and satisfaction.

There’s always a risk of data loss in complex network environments, but with SolarWinds VNQM, you can mitigate harmful disturbances and keep operations running smoothly.