How much bandwidth do I need on-board of my ship?

The calculation of how much bandwidth is required on a ship is the same as for an internet connection on land. Yet there are important details to consider:

1) The maritime airtime services can cost a multiple of tariffs on land. An exact determination of the actual need is therefore very advisable.

2) On many ships the demand for connectivity fluctuates throughout the year, such as when there are guests on board in the summer and the ship remains largely unused during the winter months.

Most tariffs can be flexibly adjusted up or down to react to changing demand, but the choice of hardware must be made in advance with a view to the maximum expected usage. Most important criteria are reflector size and the power of the transmitting unit, which ensures the capacity in upload. For more information refer to the question "What antenna size do I need?"

The internet speed depends on the bandwidth or data transfer rate. It is measured in Kbps (kilobits per second) or in Mbps (megabits per second). The distinction between upload (sending files, voice- or video services such as Skype) and download (browsing, receiving files, streaming) is important. These are shown as two separate values. Download is usually higher than upload. Note that a reference to Kbps and Mbps is not about the consumption of data volume, but about the Internet speed, which is necessary to run your applications. If the bandwidth is too low, it results in long load times. When different applications are run at the same time, they share the available bandwidth.

A common mistake is to assume that with a download speed of 1 Mbps, a 1 MB (megabyte) file can be downloaded in one second. Unfortunately, this is not the case. A megabit is 1/8 the size of a megabyte, which means you'll need an 8-Mbps connection to download a 1 MB file in 1 second.

Examples of applications and the minimum required bandwidth.

	Download	Upload
VoIP / Skype calling without video	50-150 Kbps	50-150 Kbps
Text Email	100 Kbps	100 Kbps
Web browsing	512 Kbps	128 Kbps
Music streaming	320 Kbps	-
Skype video call (low to HD quality)	500 Kbps – 1,5 Mbps	400-1000 Kbps
Youtube video streaming	500 Kbps	-
Web TV standard resolution	500 Kbps	-
Netflix streaming HD	3,8 Mbps – 5 Mbps	-

Here is another important advice, crucial for the selection of the right tariff:

Most maritime tariffs are so-called shared services. The maximum available bandwidth (MIR) is divided between a pre-determined number of subscribers. The actual speed varies for each one, depending on how much of the available bandwidth is being claimed by the other participants at this moment. With a rate of 4 Mbps and a ratio of 1:10, each participant gets at least 409 Kbps (CIR - Committed Information Rate) as a guaranteed minimum. If the other participants are not currently using their bandwidth, it can be up to a maximum of 4 Mbps (MIR) for each one.

What sounds like bad news at first glance also has a positive side. Shared services are a cost-effective alternative to so-called dedicated services if you know how to use them properly.

Calculation example for a ship with a minimum requirement of 1Mbps down / 256 kbps up:

	Tariff (Down/ UP)	Shared Ratio	Cost	Minimum (CIR) Down/ Up	Maximum (MIR) Down/ Up
1	1Mbps/ 256 Kbps	1:1	2.950 EUR/ month	1Mbps/ 256 Kbps	1Mbps/ 256 Kbps
2	4Mbps/ 1Mbps	1:4	3.150 EUR/ month	1Mbps/ 256 Kbps	4Mbps/ 1Mbps
3	4Mbps/ 1Mbps	1:10	2.700 EUR / month	409/ 101 Kbps*	4Mbps/ 1Mbps

Tariffs 1 and 2 guarantee the same speeds, whereas the 2nd tariff will run a lot better at times (up to 4 times faster internet) for almost the same price. * If it is not critical to temporarily fall below the minimum requirement, then the 3rd tariff, a 1:10 service, is again significantly cheaper. The prices are only a rough representation. Depending on satellite provider and cruising area they may be higher or lower.

Please contact us for a tailored offer. We have a wide selection of options here, either for monthly pay-as-you go contracts (invoices according to actual data usage) or unlimited plans (fixed monthly fee).