VSAT 101
All VSAT systems are not created equal 

Yacht owners and their crew all have wished for the internet while onboard for many years now.  Not too long ago we were all pleased with the few available systems that delivered up to 64K of data.  But that had its costs and of course speed and performance limitations.  Then the magic acronym VSAT caught us all.  We all want it and couldn’t wait to get it. Before you sign up there are a few things to know that all VSAT systems are not created equal!  

There are two predominate systems in marine VSAT sold today.  One is iDirect D-TDMA system and the other is DVB or DVB-S.  Station 53 utilizes iDirect’s platform which was built from the ground up around TCP/IP and provides the most efficient use of satellite bandwidth. Digital Video Broadcast (DVB) is a standard that was primarily designed to use in broadcast video applications. DVB frame format uses MPEG for broadcasting video. IP over DVB has to be encapsulated within an MPEG frame to be transported over DVB. IP packets must be segmented into MPEG 188 byte cells which further decreasing efficiency. This is a consequence of using a system optimized for digital video to transport IP packets. A maximum sized 1500-byte Ethernet packet has to be segmented into 8 or more MPEG cells. 

What does this mean to me?  Well ask yourself do you want a system that was designed for the internet and all it envelops or a system that was designed for the broadcast of TV video and adapted for the internet? 

What affect does IP encapsulation have on my applications?  As we know DVB is not designed for TCP/IP traffic. IP traffic is encapsulated within MPEG.  Traffic from you application has to be converted [encapsulated] into MPEG sent through the satellite and then un-encapsulated at the hub [earth station] and sent on its way.  This takes time and there is packet loss all of which effect your application.  

What about VoIP?  Station 53 has seen a big increase in VoIP traffic due to our available telephone numbers we supply.  We can supply you with telephone numbers from the USA, and EU countries.  We offer free calls to USA telephone numbers and free calls to most EU countries when you sign up with our EU telephone service*.  Since our system is TCP/IP based from point to point we have excellent VoIP service.  DVB remember has to encapsulate within MPEG for VoIP data and that makes for poor quality and dropped calls. 

Station 53 was created from the beginning as an iDirect system while others are now converting over.  We offered free VoIP calling when others were charging $1.50/minute.  We reduced the cost of satellite internet and increased the quality of service.  We offer CIR [Committed Information Rate], QoS and we strive to supply the best internet service at very completive prices.

Station 53 vs. DVB [Digital Video Broadcast]
 

Station 53 does not have the constraints DVB imposes. As an example, through a 500K satellite capacity Station 53 can get a TCP/IP speed of 530K.  With the same satellite capacity over a DVB network the TCP/IP throughput is only 385K. With Station 53, transported cells are sized variably depending on the size of the IP packet instead of having to conform to fixed sized cells.

DVB is the old satellite based standard that was primarily designed to use in broadcast video applications. This standard has been widely adopted due to its simplicity, easily available chipsets and cost.  DVB bases technology was widely deployed and understood by most providers.  However, DVB was primarily designed for one way broadcast of video and MPEG traffic.  DVB frame format uses MPEG for broadcasting video.  The problem is that IP over DVB has to be encapsulated within the MPEG frame to be transported over DVB.  IP packets must be segmented into MPEG 188 byte cells which further decreases efficiency. This is a consequence of using a system optimized for digital video to transport IP packets.  A maximum sized 1500 byte Ethernet packet must be segmented into 8 or more MPEG cells.

IDirect has pioneered TCP/IP over satellite technology in the industry to ensure the most efficient use of satellite bandwidth.  As demand for IP over satellite continues to grow Station 53 offers IP services at a lower cost, at the same time provides world class service with all the TCP/IP enhancements over satellite to its customers.

Station 53 along with iDirect provides an industry leading solution allowing networks to simultaneously support data, voice and video traffic.  This system delivers unparalleled features and functionality which guarantees VoIP quality.  This system also supports H.323 or SIP compliant VoIP solutions thus allowing our customers the freedom to choose their VoIP providers.