How to Identify Network Problems & Diagnose Network Issues

Just because your network is "UP," doesn't mean it’s working well! Network issues like choppy VoIP, jerky video calls, and network and application slowness issues can affect your business in drastic ways - which is why it’s important to know how to identify network issues for network performance troubleshooting.

There are many problems that can affect network performance, and some of them are very complex to identify and understand. Intermittent network issues frustrate users, affect business productivity, and are a nightmare for all IT administrators because they are the most difficult to solve.

That’s why it’s important to agree on the vocabulary surrounding this subject before thinking of identifying solutions.

In this article, we'll be defining the vocabulary surrounding network issues to teach you how to identify network problems, diagnose network issues, and find solutions.

When it comes to identifying and diagnosing network issues, your secret weapon is a Network Monitoring software. A Network Monitoring (or Network Performance Monitoring) tool monitors end-to-end network performance to identify network issues affecting your end-users and customers - even if those network problems may reside outside of your local network infrastructure.

We recommend a tool like Obkio Network Performance Monitoring Software because it does the work for you.

• Synthetic Traffic simulates the end-user perspective to identify issues
• Decentralized end-to-end monitoring of network locations with Monitoring Agents
• Continuous monitoring identifies intermittent issues that are hard to pinpoint
• Monitoring Agents collect data to diagnose network issues
• Measures network performance metrics like jitter, packet loss, throughput and more
• Troubleshoot network issues with Device Monitoring & Traceroute features

Get started with Obkio’s Free Trial!

The applications that run over your network don’t all have the same performance requirements. Some performance variations can affect VoIP or video quality, but will have no effect on web browsing or email activity.

The common causes of network issues are almost always the same. When you identify network performance issues, here are some common ones:

Network performance issues related to resource issues can mean different things, from equipment problems to high CPU usage. Let’s break down some of the most common resource issues:

1. Network Equipment & Devices: Sometimes, network issues occur within network equipment or devices like Firewalls, Routers, Switches, Wifi APs. Problems can be due to bad configurations, faulty connections, and even packet loss. Obkio’s network device monitoring solution easily monitors any SNMP-enabled network devices to ensure performance and diagnost network issues affecting network devices.
2. High CPU Usage: The most common cause of high CPU usage is when your network becomes bogged down by enormous amounts of traffic. CPU usage can increase drastically when processes require more time to execute or when a larger number of network packets are sent and received throughout your network. High CPU usage can bog down your network, or leave not enough CPU for other processes.
3. High Bandwidth Usage: When someone or something on your network begins monopolizing bandwidth by downloading gigabytes worth of data, possibly by video, it creates a congestion in your network. Network congestion due to high bandwidth usage leaves not enough bandwidth for other parts of your network — which is when you can start experiencing problems like slow download speed over the internet.

Network performance issues can allow for basic connectivity functions, but they do not allow for high performance. These failures can be either steady or intermittent, with the latter being the most challenging to identify and troubleshoot.

1. Network Slowness: Network slowness occurs when a computer network is operating at a slower-than-normal speed, often resulting in sluggish internet browsing or delays in accessing files or applications.
2. Latency: Latency is the time it takes for a message to travel from one point on the network to another. High latency can cause delays and slow down network performance, making it harder for users to access data and applications.
3. Packet Loss: Packet loss occurs When packets of data are lost or dropped during transmission. It can lead to retransmissions, which can slow down network performance and increase latency.
4. Network Congestion: When there are too many devices using the same network resources, the available bandwidth can cause network congestion, cleading to slower network speeds and longer wait times.
5. Packet Duplication: Packet duplication can occur when packets are duplicated during transmission, resulting in additional network traffic and potentially affecting network performance. When packets are duplicated, the receiving device may process the same data multiple times, leading to additional processing overhead.
6. Packet Reordering: Packet reordering can occur when packets are received out of order. This can be caused by network congestion or delays in packet delivery. Packet reordering can cause additional processing overhead as the receiving device has to reorder the packets before processing them.

Network availability issues refer to problems that prevent users from accessing the network or network resources. When a network is unavailable, users may experience downtime, loss of productivity, and potential loss of revenue. Some common network availability issues include:

1. Network outages: Network outages occur when the network is unavailable due to hardware failure, power outages, or other issues. Network outages can cause significant disruptions in service and may require significant time and resources to resolve.
2. Network congestion: Network congestion occurs when there is a high level of network traffic, causing delays and potentially making the network unavailable for some users. Network congestion can occur due to insufficient bandwidth, a large number of users accessing the network simultaneously, or other issues.
3. Security attacks: Security attacks, such as distributed denial-of-service (DDoS) attacks, can cause network availability issues by flooding the network with traffic or disrupting network resources. These attacks can cause network downtime and require significant resources to mitigate.
4. Configuration errors: Configuration errors can cause network availability issues, such as misconfigured network devices or incorrect routing tables. These errors can cause disruptions in network connectivity and may require troubleshooting to resolve.
5. Software bugs: Software bugs in network devices or network applications can cause network availability issues by causing devices to crash or behave unexpectedly. These issues can be difficult to diagnose and may require software patches or upgrades to resolve.

Network device issues refer to problems that occur with the physical devices that make up a network infrastructure. These issues can be caused by hardware failures, software bugs, or configuration errors, among other factors. Some common examples of network device issues include:

1. Defective Cables or Connectors: It may seem obvious, but some network issues may occur with the hardware outside of the network. Hardware problems like defective cables or connectors can generate errors on the network equipment to which it is connected. A copper, cable, or fiber-optic cable can be damaged, which will likely reduce the amount of data that can go through it without packet loss.
2. Hardware failures: Hardware failures, such as a failed router, switch, or network card, can cause disruptions in network connectivity and lead to network downtime. These issues can be caused by component failures, power surges, or other factors.
3. Firmware or software bugs: Firmware or software bugs in network devices can cause devices to behave unexpectedly or fail to function properly. These issues can be difficult to diagnose and may require updates or patches to resolve.
4. Configuration errors: Configuration errors can cause network device issues, such as misconfigured routing tables or incorrect access control lists. These errors can cause disruptions in network connectivity and may require troubleshooting to resolve.
5. Compatibility issues: Compatibility issues between network devices or software can cause problems, such as incompatible firmware versions or mismatched network protocols. These issues can cause disruptions in network connectivity and may require updates or configuration changes to resolve.
6. Overheating or power issues: Overheating or power issues can cause network devices to fail or shut down, leading to network downtime. These issues can be caused by inadequate cooling or power supply capacity, among other factors.

DNS errors essentially happen because you’re unable to connect to an IP address, signalling that you may have lost network or internet access. So, your site can simultaneously appear online for you, but offline to your visitors. DNS issues occur with the DNS infrastructure responsible for translating human-readable domain names into IP addresses that computers can use to connect to websites and other network resources. Some common DNS issues include:

1. DNS server failure: When a DNS server fails, it can prevent users from accessing websites and other network resources. DNS server failure can be caused by hardware failure, software bugs, or configuration errors.
2. DNS cache poisoning: DNS cache poisoning occurs when attackers manipulate the DNS cache to redirect users to fraudulent websites or malicious resources. This can lead to security breaches and potential loss of data or other sensitive information.
3. DNS misconfiguration: DNS misconfiguration can cause issues, such as misconfigured name servers or incorrect DNS records. These issues can cause disruptions in network connectivity and may require troubleshooting to resolve.
4. DNS propagation delay: DNS propagation delay occurs when changes to DNS records are not immediately propagated throughout the DNS infrastructure. This can cause disruptions in network connectivity and may require patience until the propagation is completed.
5. DNS overload: DNS overload occurs when DNS servers are unable to handle the volume of requests they receive, leading to slower response times or even network downtime. DNS overload can be caused by a large number of users accessing the network simultaneously or other factors.

1. Slow internet speeds: Slow internet speeds can be caused by a variety of factors, including insufficient bandwidth, network congestion, or distance from the network access point.
2. High latency: High latency can cause delays when accessing Internet resources, such as slow page load times or delays in sending and receiving data. This can be caused by network congestion, long distances between network endpoints, or other factors.
3. Intermittent Internet connectivity: Intermittent Internet connectivity issues can cause disruptions in internet access, such as dropped connections or intermittent outages. These issues can be caused by hardware failures, network congestion, or other factors.
4. Service provider issues: Service provider issues, such as network outages or maintenance, can cause disruptions in internet access or lead to slower internet speeds.
5. Interference in the Wireless Network: Wireless interference occurs when something disrupts or weakens the Wi-Fi signal transmitted from your wireless router. Very common household items, like microwave ovens or cordless phones, are slowing down your home Wi-Fi network performance. if you live in a densely populated area, your neighbors’ Wi-Fi networks could actually be interfering with your own. This is particularly true if you’re using a 2.4GHz wireless router.
6. Internet Outages: Internet outages occurs when a portion of the internet, or the entire internet, becomes inaccessible for an extended period of time. An Internet outage or failure can occur at any time, the first challenge for network administrators is to quickly identify the events that can cause breakdowns as well as the precise time of the event.

While users are usually quick enough to report problems, it’s of course ideal to intercept the problem and resolve it before it affects users.

Knowing how to identify network issues begins with measuring network performance using precise network metrics. You’ll then need to familiarize yourself with all your application performance requirements to identify the network performance thresholds to be respected, and to ensure that these applications can work properly.

Some of the most common network metrics that you should be looking at are:

1. Latency: Within a network infrastructure, latency refers to the measure of time it takes for data packets to reach their destination when traveling across a network. It is usually measured as a round trip delay, in milliseconds (ms), taking into account the time it takes for the data to get to its destination and then back again to its source.
2. Jitter: Jitter is a huge problem when using real-time applications such as unified communications, including IP telephony, video conferencing, and virtual desktop infrastructure. Simply put, jitter is a variation in delay. Otherwise known as a disruption that occurs while data packets travel across the network.
3. Packet Loss: Packet loss refers to the number of data packets that were successfully sent out from one point in a network, but were dropped during data transmission and never reached their destination. It’s important to know how many packets are being dropped across your network to determine good or poor network performance.
4. Throughput: Throughput refers to the amount of data passing through a network and traveling from point A to point B in a determined amount of time. When referring to communication networks, throughput is the rate of data that was successfully delivered over a communication channel.
5. Packet Duplication: Packet duplication refers to when data packets are duplicated somewhere in the network, and are then received twice at their destination. The source of the data sometimes believes that a data packet was not transmitted correctly because of packet loss, and may retransmit that packet. The destination source may have already gotten the first packet, and will receive a second duplicate packet.
6. Packet Reordering: Packet reordering occurs when data packets arrive at their destination in the wrong order. This can happen for various reasons, such as multipath routing, route fluttering, and wrong QoS queue configuration.

18 Network Metrics: How to Measure Network Performance

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Networks are becoming more and more complex with every technological advancement. As hosted services continue to gain popularity, applications are being hosted further and further away from users.

Events that can affect the maintenance of critical applications can occur anywhere: in an internal LAN, wired or wireless network, with the Internet or WAN provider, or in the internal network of a service provider.

The second challenge for network administrators when knowing how to detect and diagnose network issues is to precisely identify a number of points used for network troubleshooting. To do so, perform a network assessment to identify:

As I talked about at the start of the article, there are a variety of network issues that can interrupt your network performance. To know how to solve these problems, you need to actually understand what they are. A network performance monitoring software will monitor and measure network metrics and report back if it finds any issues, with details about what the issue is, and what caused it.

Networks are vaste infrastructures, especially modern networks that can span over a variety of different locations. That means that a network issue can be hiding anywhere. It’s important to identify where exactly in your network a network performance issue has occurred.

Using Monitoring Agents, Obkio allows you to deploy Agents in key network locations, set up monitoring sessions, and continuously monitor network performance between Agents. That means that, if a network issue occurs, you can easily see which Agent, in what location, has identified it.

Here are some common areas where network issues can occur:

1. End-user devices: End-user devices, such as desktops, laptops, smartphones, and tablets, can experience network issues due to outdated drivers, misconfigured network settings, or hardware failures.
2. Local network: Local network issues can occur due to misconfigured network devices, such as routers, switches, or firewalls. Malfunctioning network devices or network cables can also cause local network issues.
3. Wide Area Network (WAN): WAN issues can occur due to internet connectivity issues, ISP outages, or slow internet speeds. DNS issues or misconfigured WAN devices can also cause WAN issues.
4. Cloud infrastructure: Cloud infrastructure issues can occur due to connectivity issues with cloud service providers, network congestion in the cloud, or issues with cloud applications.
5. Network core: Issues with the network core, such as malfunctioning switches or routers, can cause widespread network issues that impact multiple devices or users.

As I mentioned earlier, modern networks are vast infrastructures, and many businesses may have several employees working to manage different parts of the network. Once you located a network issue, and what exactly it is, you can then easily decide who is responsible for fixing it.

After you’ve collected all the information you need to identify the network issue, where it’s located, and why it happened, you can then assess what the next steps are in terms of solving the problem. That could be reaching out to your ISP or MSP, or bringing the problem to your network administrator to fix it internally.

1. Check physical connections: Make sure all cables, routers, switches, and network interface cards (NICs) are securely connected and not damaged.
2. Update network drivers and firmware: Outdated drivers and firmware can cause network connectivity problems. Check for updates and install the latest versions.
3. Reset network hardware: Resetting routers and switches can help clear network congestion and resolve intermittent connection problems.
4. Optimize network settings: Adjusting network settings such as DNS servers, IP addresses, and network protocols can help improve network connectivity and speed.
5. Reduce network traffic: High network traffic can cause intermittent connectivity problems. Limiting the number of devices connected to the network and reducing file transfers and downloads can help alleviate network congestion.
6. Contact your ISP: If the above steps do not resolve the issue, contact your internet service provider (ISP) to check for network problems on their end.
7. Document the issue: Keep a log of when the issue occurs, how long it lasts, and any other relevant details. This can help identify patterns and assist with troubleshooting efforts.
8. Monitor the network: Even after you have resolved the issue, it is important to monitor the network to ensure that the issue does not reoccur or cause additional problems. Ongoing network monitoring and network connectivity monitoring can help identify potential issues before they become significant problems and can help maintain optimal network performance.

The increase in the number and duration of network outages can have a detrimental effect on multiple parts of your business. The longer these problems go unnoticed, the more damage they can potentially cause.

Network issues have particular effects on:

Some consequences for IT services include:

• VoIP and choppy video calls
• Slow Internet performance or Internet problems
• Slowdown of critical applications such as ERP, CRM, finance, and ecommerce systems.
• Failing Citrix, RDP or Terminal Server sessions
• Low transfer rate

Some consequences for users and clients include:

• Lost productivity
• Frustration and disengagement
• Bad customer experience

Some consequences for your business include:

• Lost productivity
• Overworked IT infrastructure
• Increased operating costs
• Damaged reputation
• Loss of income

The main task of an IT administrator should not simply be to put out fires, but rather to support the business in its development and day-to-day operations.

To succeed in getting out of the deep end, an IT manager must be able to prevent performance problems by detecting them as soon as they happen. Quick detection and prevention will help prevent catastrophic consequences from taking shape and avoid the time IT managers will have to spend on crisis management.

It’s therefore essential to be able to understand the consequences of network issues and to implement solutions to detect them.

How to Detect and Identify Intermittent Network Problems

Learn how to detect intermittent network problems to troubleshoot performance issues that are hard to catch with Obkio Network Monitoring software.

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Even the best designed networks are not immune to problems.

All IT managers generally agree on one thing. The question is not whether or not there will be network problems, but rather WHEN they will happen and what actions will be taken to fix them as soon as possible.

Once you detect network problems, and diagnose issues by collecting the information we mentioned above, the next step is Network Troubleshooting. We have a complete article on Network Troubleshooting, so make sure read that next to solve the network problems you identified.

When troubleshooting network issues or network slowness, several tools are available in the vault of a network administrator such as:

1. Traceroutes: to identify route, latency and packet loss between two sites. See visual traceroute results and troubleshoot with traceroutes using Obkio's Vision Visual Traceroute tool.
2. Speed Tests: which allow you to validate if the bandwidth you need is readily available. You can also learn more in our blog post on How to Monitor Network Speed.
3. Prioritization and QoS: which increases network efficiency in the event of congestion and prioritizes applications more critical or sensitive to performance problems such as VoIP or video.
4. Network Equipment Monitoring solutions like Fault Monitoring that perform SNMP reading on the equipment.
5. Network Perforance Monitoring: Like we mentioned at the beginning of the article, a Network Monitoring tool is your biggest asset. It monitors performance, alerts you of network issues, and collect information to help you diagnose. A complete software, like Obkio, also offers the troubleshooting tools mentioned above.

Obkio is a simple Network Monitoring and Troubleshooting SaaS solution for Enterprises and MSPs that allows users to continuously monitor the health of their network and core business applications to improve the end-user experience!

Deploy physical, software or public Monitoring Agents at strategic locations in your business’ network such as data sites, remote sites, external client sites, or public or private clouds and easily identify the causes of intermittent VoIP, video, and applications slowdown in seconds.

• 14-day free trial of all premium features
• Deploy in just 10 minutes
• Monitor performance in all key network locations
• Measure real-time network metrics
• Identify and troubleshoot live network problems

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