Packet loss refers to the failure of data packets to reach their intended destination when being transmitted from one computer to another over a network. It occurs when one or more packets of data traveling across a network fail to reach their destination.
Packet loss is a critical issue in computer networks and can significantly degrade network performance and affect services like video streaming, voice over IP (VoIP), online gaming, and video conferencing that rely on steady packet flow.
Identifying and fixing the root causes of packet loss is crucial for maintaining high-quality network connections and optimal user experience.
What are the Causes of Packet Loss?
Network congestion
Congestion happens when too much data is being transmitted on a network at the same time. This leads to overutilization of bandwidth which causes routers and switches to start dropping packets when their buffers overflow.
Congestion and queueing delays are common causes of packet loss in both wired and wireless networks. Network upgrades or traffic shaping techniques may be needed to resolve congestion.
Faulty hardware
Issues with network infrastructure hardware like NIC cards, cables, routers, switches, or modems can also lead to corrupted or dropped packets before they reach their final destination.
Defective hardware like loose connectors, deteriorated cables, malfunctioning NICs, or switches with flapping ports can introduce errors into packet transmission resulting in loss. Replacing aging hardware is key.
Interference in wireless networks
Wireless networks are highly prone to interference from other devices operating in the same radio frequency band such as Bluetooth devices, microwaves, cordless phones, etc.
Such interference leads to degradation in signal quality which manifests as high packet loss. Using a 5GHz band instead of 2.4GHz, placing the router in an optimal location away from other wireless devices can help mitigate this.
Software bugs
Bugs, flaws in network driver software, router firmware, VPN applications, etc. can also be responsible for randomly dropped packets. Outdated network software components cause more issues. Regular updates and patches are essential.
What are the Effects of Packet Loss?
- Slow download/upload speeds: Packet loss reduces the effective bandwidth available for transmitting data across a network. Retransmission of dropped packets causes congestion control mechanisms to kick in, slowing down overall throughput. This manifests as sluggish download and upload speeds.
- Choppy voice/video calls: Real-time interactive services like video conferencing, voice-over IP, and online gaming rely on a steady stream of packets with minimal lag or jitter. Random packet loss leads to choppy, distorted audio as well as freezing and pixelation of video. Dropped packets can significantly degrade quality.
- Webpages failing to load: Packet loss causes data transmission errors and broken connections which leads to timeouts when loading webpages and inability to access certain websites. Pages may fail to load completely or only partially.
- Failure of apps to work: Online apps and cloud-based services may stop working properly or become unreachable if packet loss crosses a certain threshold as packets carrying critical application data are dropped.
How to Fix Packet Loss?
- Router reboot
Simply rebooting or power cycling the router can help clear up software glitches, memory leaks, or transient network congestion that is leading to packet loss. This quick fix may help as it resets the router’s CPU and clears all caches.
- Firmware, driver, and software updates
Outdated firmware versions on routers, flawed network driver software on devices like laptops, or bugs in VPN client programs are common culprits behind high packet loss. Updating to the latest firmware and network software eliminates such bugs and software issues causing random packet drops.
- Checking for interference
For WiFi networks, identify sources of wireless interference like neighboring networks, Bluetooth devices, microwaves, baby monitors, etc., and minimize their impact by choosing different channels or relocating devices. Alternatively, use wired Ethernet connections wherever possible to avoid interference.
- Inspecting hardware
Carefully inspect physical hardware like Ethernet cables, WiFi adapters, routers, switches, or modems for any signs of damage or degradation. Replace components like cables with loose connectors, crimped cables, NIC cards with overheating issues, etc. as defective hardware frequently causes packet loss.
- Testing with different hardware
Try substituting the suspected faulty hardware component with a working spare component like an Ethernet cable or WiFi client adapter and check if packet loss improves. This confirms if the issue is arising from a defective hardware component.
- Checking packet loss over VPN
Determine if packet loss persists when connected to a different network over VPN. If the VPN connection does not show packet loss, then the issue is likely between your premise and ISP.
- Monitoring traffic
Use network analyzer tools like Wireshark to capture and inspect traffic flows. Check if certain devices like CCTV cameras or computers are overloading the network with large transfers. Limit their bandwidth if needed.
- Contacting ISP
For chronic packet loss persisting despite the above steps, contact your Internet Service Provider to troubleshoot and resolve issues like line noise, congestion, or faults in their network infrastructure. ISPs can monitor traffic flows across their backbone to isolate the problem area.
- Changing wireless channels
Try changing the wireless router radio channel to less congested ones like 1, 6, or 11 since congestion on certain channels can lead to collisions and dropped packets.
- Checking for faulty lines
For wired networks, damaged underground cables or telephone lines introducing noise can cause packet loss. ISP may need to repair or replace aging lines.
Preventing Packet Loss
- Proactive monitoring
Continuously monitoring network performance metrics like packet loss, latency, jitter, etc. allows you to identify and troubleshoot issues before they severely impact users. Quickly fix sources of loss like congestion or hardware failures.
- Limiting connected devices
Having too many devices connected to the same WiFi network can create contention and collisions leading to loss. Audit and limit the number of client devices per AP radio. Set bandwidth caps on heavy users.
- Wired over Wireless
For critical connections, use wired Ethernet instead of WiFi to avoid intermittent loss due to interference or low signal issues. Wired networks offer reliable low latency connectivity ideal for VoIP calls, gaming, etc.
- Improving WiFi coverage
Eliminate WiFi dead zones and enhance coverage through mesh networking, concealed cabling, or placement of additional access points. This reduces spotty connections and packet loss, especially for mobile clients.
- Upgrading internet plan
Faster internet plans with more bandwidth allow you to support more concurrent devices and traffic flows without congestion-related packet loss. Upgrade plan if speed tests show regular maxing out of provisioned bandwidth.
- QoS and traffic shaping
Implement Quality of Service and traffic shaping policies to prioritize key traffic like VoIP or video over bulk transfers. This prevents critical packets from being discarded during congestion.
- Using 5GHz WiFi
The 5GHz channels offer better performance with less interference than the commonly used 2.4GHz channels. Upgrade clients and enable a 5GHz network to reduce airtime contention and packet loss over WiFi.
- Optimizing WiFi configuration
Tune WiFi parameters like channels, transmit power, RTS/CTS thresholds, etc. optimally to reduce radio interference and retransmissions. Assign channels intelligently.
- Updating network infrastructure
Replace aging network infrastructure like routers, switches, and wireless access points with the latest models supporting higher bandwidth and performance. Newer hardware handles congestion better.
A combination of proactive performance monitoring, making judicious hardware upgrades, following best practices in wireless network configuration, and actively managing connected devices is key to minimizing packet loss issues.
Wrap-Up: Reducing Packet Loss
In summary, packet loss is a major impediment degrading network performance and user experience.
Proactively monitoring metrics, updating network software/hardware, fixing faulty components, isolating wireless interference, contacting ISPs to resolve infrastructure issues, and upgrading capacity are key steps to address packet loss issues.
Following best practices around wireless network planning, switching to wired connections for real-time apps and QoS policies also helps prevent packet loss.
A proactive approach to capacity planning and maintenance is crucial for ensuring high reliability across modern networks.