What is Broadband Speed?
Broadband speed is the rate at which data is transported, measured in megabits per second (Mbps). The higher the broadband speed a service offers, the more data can be transferred per second. Broadband speed applies to both the rate at which that data passes through to your device from the internet or server (‘download’) and the rate at which data passes from your device to the internet or server (‘upload’).
Broadband speed is determined by the network access type (i.e. you may have an internet connection using ADSL, hybrid fibre cable, FTTN, FOTA, etc), and a range of other factors as outlined below. Because of variations within the retail service provider’s broadband network (including access provided by ProtekAI or another wholesale access provider) you may not always get the same speed all the time.
Broadband services are often marketed according to the access line connection speed, the theoretical speed which should be achieved (or very close to achieved) in ideal circumstances. The speed of your broadband service will not exceed the ‘access line connection speed, and will sometimes be less. This is because consumer-grade broadband services available for sale in South Africa are not a dedicated connection between your home and the internet. They are a shared connection offering variable broadband speeds subject to contention by multiple users, the speed experienced by an individual user can be reduced when there is high demand from these other users.
What impacts broadband speed?
Computers communicate with each other across a network by sending blocks of information, called packets. When packets get disrupted or lost, it can affect the performance of your internet connection and therefore your browsing or viewing experience.
There are many factors that affect the actual speed you experience. Examples of these include your location in relation to the broadband node, the gateway software being used, whether the site you are trying to access is based(hosted) in South Africa or overseas, your home wiring, your home network set-up (e.g. access point location/quality, Wi-Fi) and internet traffic congestion.
When you download data from a server, the overall broadband speed and performance you experience depends on the overall network path all the way to your device in the home. This includes the host server’s capabilities, particularly if multiple users are trying to download from that server at the same time. These factors are common to all broadband technologies.
Peak Hours
Busy, or peak hours are the times when slower or more variable speeds are most common, and typically fall between 5.00 pm to 11.00pm. Peak hours are the periods when the largest demands are being placed on the internet networks and servers that provide content and services. During the busiest hours, an individual’s upload and download speed tests may vary from the maximum access connection speed down to significantly slower speeds. During the busiest hours, for example, typical off-peak average speed of 10Mbps may slow significantly.
In some cases, congestion may be the key determining factor for speed outcomes during peak hours. Those outcomes may differ widely across different Retail Service Providers. Some consumers are very cost conscious and will prefer to pay for a lower-priced, more congested service, even if the average performance is not as strong as that of higher priced offerings.
Technology (Access Type):
All broadband networks will be impacted by constraints relating to shared capacity – that is, multiple consumers sharing access to the infrastructure. Next generation networks – such as the ProtekAI network – are typically capable of achieving high data speeds but these networks are also impacted by shared capacity. The access types recommended by your Retail Service Provider will depend on what is available where you live.
In-household set up:
The number of users accessing the internet within a single household may have a noticeable impact on service performance. This is more likely when that household has a relatively low maximum access speed.
Speed will also be impacted by the access point you use. If you think your access point may be a factor in not getting the speed you think you should be getting, speak to us or follow the troubleshooting tips available from your access point manufacturer.
There is further information in our Troubleshooting Guide on what to consider for your in-household set up.
What do different applications need?
End-user experience with high bit-rate activities such as downloading/uploading will be improved by a high-speed service. Streaming high definition video can also require moderately high bit-rates - more so if multiple householders stream simultaneously. However, speeds higher than that required to avoid buffering may not improve the user experience of streaming video.
This section includes some technical information.
Does not require much speed or capacity and will typically work the same regardless of broadband speed. If you receive big attachments these may take additional time to download.
Web browsing
Does not require much speed or capacity. Upload speed is relatively unimportant.
Audio or video streaming
The coded video rate depends on the quality of the content being streamed (e.g. standard definition video or high definition video) and the compression technology (codec) being used by the content provider. Standard definition video typically operates optimally at 4 Mbps, while high definition video typically operates at 6-8Mbps. Audio content requires much lower speeds, typically 500-800 kilo-bits per second (i.e. 0.5-0.8 Mbps).
Audio and video streaming employ “buffering” whereby a small amount of content (e.g. from a few seconds to minutes) is downloaded to your device and stored in advance of its playback. This delays the playback of the video by that interval, but means it can tolerate short pauses or decreases in speed without interrupting playback, as long as the download speed exceeds the content streaming rate for most of the time. If the available download rate is below the video rate the buffer gradually empties and when it empties the video stops. Most streaming services can adjust their video speed down to avoid interrupting the video when download speeds reduce, and the user may notice lower picture quality at those times.
The requirements to maintain acceptable streaming video quality are therefore:
Access line speed which is significantly higher (by 30% to 50%) than the video streaming rate to allow the buffer to refill when depleted.
An uncongested network path from the video server that can download on average at twice the video streaming rate or faster.
Low packet loss
Minimal or no dropouts.
Packet loss can also result in slower downloading that can result in video quality degradation or stops in a similar manner to congestion.
Downloading video to hard drive and playing while downloading
This is the same as streaming video (see above), except that instead of using a temporary buffer, a copy of the downloaded video is retained permanently. As with streaming video, the average download speed needs to exceed the bit-rate of the content.
Voice over IP (VoIP)
Only requires a low speed –i.e. greater than 0.5 Mbps is normally acceptable. However, packet loss and latency can have a high impact on VoIP user experience if conversations are delayed. VOIP may suffer during peak hours if the broadband link to the house is being used for multiple applications / by multiple users at the same time.
Gaming
6-10Mbps is sufficient for playing most online games. However, packet loss, dropouts, server location and delays can significantly affect user experience.