Latency (delay) describes the time span a data packet needs to travel within a network from the source to the destination. It is a crucial factor for the speed and efficiency of data transmission.
How is latency measured?
Latency is typically measured in milliseconds (ms). This time indicates how long it takes for a data packet to reach its destination and for the confirmation to return to the sender. This measurement is performed using network diagnostic tools like ping or traceroute. The process is referred to as Round-Trip Time (RTT) and shows the time needed for sending and receiving a message.
Latency times in different network environments
Latency times vary greatly depending on the network type. Here are some examples:
- Local Area Network (LAN):
Here, the delay is often the lowest, typically under 1 ms. This is ideal for fast data transfers within a building or campus. - Wide Area Network (WAN):
WANs connecting distant locations can have latencies from 20 ms to 100 ms or more. The values depend on the distance and the quality of the connection. - Mobile networks:
The latency varies depending on the technology. For 4G, it’s about 50 ms, while 5G can achieve latencies of up to 1 ms. 5G significantly reduces latencies, which is important for real-time applications. - Satellite internet:
The delay is particularly high due to the large distance the signals travel, typically between 600 ms and 1200 ms.
Impact of data traffic and network congestion
Data traffic in a network directly influences latency. High data traffic can lead to congestion, which increases latency. This is comparable to traffic on a highway during rush hour: The more cars on the road, the slower the traffic becomes.
Measures to reduce latency
Various measures can be taken to reduce latency:
- Quality of Service (QoS):
This configuration on routers prioritizes data traffic and grants critical applications preferred access. - Traffic Shaping:
This technique controls the speed of certain data streams to optimize network performance.
Significance and impacts of latency on digital services
Latency affects the response speed of digital services. For streaming services, online games, and VoIP communication, high latency can lead to delays and a poor user experience. Services like Netflix and YouTube optimize their networks to minimize latency and avoid interruptions.
In VoIP and video conferencing systems, low latency is essential for clear and effective communication. Providers continuously work on improving latency through technologies such as WAN optimization and improved routing.
Optimizing and reducing latency
The following methods reduce latency:
- Optimization of route selection:
Network paths with the least delay should be chosen. - Use of Content Delivery Networks (CDN):
These networks store content at various locations to reduce the distance to end users. - Minimization of protocol overhead:
Use more efficient protocols and reduce additional data traffic. - Compression: Compression reduces the amount of data transmitted.
