The following 10 tips are provided to help obtain the best possible IP connection between two codecs, without paying for Quality of Service (QoS).
1.Always use the best quality Internet Service Provider (ISP). Tier 1 service providers are best as their infrastructure actually makes up the internet ‘backbone’. Wikipedia lists the major service providers that make up the internet backbone at: http://en.wikipedia.org/wiki/internet_backbone. In Australia Telstra is equivalent to one of these service providers.
2.You will get the best quality connection if both the local (studio) and remote codecs use the same ISP. This can substantially increase reliability, audio bandwidth and reduce audio delay. Using the same service provider nationally can give better results than using different local service providers. This is especially true if one of the service providers is a cheap, low-end domestic service provider, which buys its bandwidth from other ISPs. Second and third tier providers sublease bandwidth from first tier providers and can result in connection reliability issues due to multiple switch hops. We also highly recommend using First Tier ISPs if connecting two codecs in different countries.
3.Sign up for a business plan that provides better performance than domestic or residential plans. Business plans typically have a fixed data limit per month with an additional cost for data beyond that limit. In addition, Service Level Agreements (SLA) will often provide better support and response times in the event of a connection failure. Domestic plans are often speed-limited or “shaped” when usage exceeds a predefined limit. These plans are cheap but they are dangerous for streaming broadcast audio.
4.Ensure that the speed of the connection for both codecs is adequate for the job. The minimum upload speed recommended is 256 kbps for a studio codec and 64 kbps for a field unit connection.
5.Use good quality equipment to connect your codecs to the internet. (Tieline successfully uses Cisco® switching and routing equipment.):
•If you are using a DSL or ADSL connection make sure you purchase a high quality modem that can easily meet your speed requirements. This is especially important if you are over 4 kms from an exchange.
•If you have multiple codecs connected to a local area network (LAN) please ensure that your network infrastructure is designed for media streaming and not domestic usage. Tieline has tested several cheap 8-port switches that lose more packets between local computers than an international IP connection between Australia and the USA!
•If using a wireless connection ensure that the antenna signal strength received is strong. The type of antenna used and the amount of output gain also affects connection quality.
Important Note: You should be able to stream audio between two codecs on your LAN and get high send/return ‘link quality’ readings of around 99. If you see less than this then get a network engineer to investigate the issue. |
6.Once your internet connection is installed at the studio check that the connection performance is approximately what you ordered and are paying for. A connection can perform below advertised bit rates if:
•There is an error in ISP configuration;
•There is an error in modem configuration;
•There is a poor quality line between the studio and the exchange;
•There are too many phones or faxes connected to the phone line; or
•Line filters have been connected incorrectly.
7.Use a dedicated DSL/ADSL line for your codecs. Do not share a link with PCs or company networks. The only exception to this rule is if an organization has network equipment and engineers that can implement and manage quality of service (QoS) on its network.
8.Use UDP as the preferred audio transport protocol.
9.When using UDP ensure the total bit rate (audio bit rate plus header bit rate) is no more than 80% of the ISP connection rate. IP headers require around 20 kbps in addition to the audio bit rate. For example, with a 64 kbps connection the audio bit rate should be (64-20) x 0.8 = 31.2 kbps or lower.
10.Wireless IP connections can easily become congested and result in packet loss and audio drop-outs. It is very difficult to guarantee connection quality when there is no way of knowing how many people are sharing the same wireless connection.
Important Note: Be careful when using cell-phone connections at special events where thousands of people have mobile phones. This can result in poor quality connections and audio drop-outs if cell-phone base stations are overloaded. |
•Don’t share a router for other purposes when you are streaming to ensure you have the most bandwidth possible.
•The 5GHz band handles interference better and tends to be less congested than 2.4GHz.
•Try to minimize your distance from the Wi-Fi Access Point if possible. This can make a huge difference in reliability.
•You may be able to increase your speed by switching to a less busy channel. Download a wireless channel analyzer app such as Wifi Analyzer for Android or a desktop program such as NirSoft's Wi-FiInfoView for Windows. Macs have the tool built in. These programs show each channel on each Wi-Fi frequency, and the ones nearby networks are using. If you discover you're on a crowded channel, you can manually change it. Type your router's IP address into your web browser. (The IP address is usually on the back of the router, or you can Google your router's model. You can also use http://setuprouter.com/). Enter your username and password, then click to view Wi-Fi settings and select the channel recommended by the Wi-Fi analyzer program.
Complete the following check list and aim for a score of at least 8 out of 10 before going live.
Number |
Check |
Result |
1 |
Using a reputable Tier1 ISP that’s part of internet backbone. |
|
2 |
The same ISP is being used for both codec connections. |
|
3 |
The ISP Plan is a Business Plan or equivalent. |
|
4 |
The ISP connection speed is adequate. |
|
5 |
Equipment is high quality and suitable for media streaming. |
|
6 |
The ISP connection speed has been tested and is suitable. |
|
7 |
The ISP connection is not shared with other PCs or devices. |
|
8 |
UDP is being used as the audio transport protocol. |
|
9 |
No more than 80% of ISP connection bandwidth is being used. |
|
10 |
There are no wireless connections being used. |
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