MDSA Gigabeam MVDDS system is an asymmetrical network system delivering data services at a high data rate to a large number of user stations via terrestrial MDSA Technology Transmitters using DVB standards. By using standard technology (which is also used for commercial Set-top boxes) and taking advantage of the high data rates available in the microwave spectrum, a very favorable cost/performance ratio can be achieved. The current implementation can deliver data at a rate up to 2.2 Gbps per sector.
The architecture of the MDSA Gigabeam System is based on an asymmetric network, where the downstream channel has a much higher bandwidth allocation (faster data rate) than the upstream. The reasons for the asymmetric network are derived primarily from the asymmetric nature of Internet applications. Activities such as World Wide Web (http) surfing send much more data down to the computer than from the computer to the network. Mouse clicks (URL requests) and e-mail messages are not bandwidth intensive in the upstream direction. Image files and streaming media (audio and video) are very bandwidth intensive in the downstream direction.
A central server station sends the data packets over the MDSA Gigabeam Transmitter directly to an end-user. The end-user can be connected back up in a number of ways, WiFi, WiMAX, 802.11 depending on Frequency Allocation. This connection, called "the return link", is used for transmitting back to the Internet.
The System can operate in one of three modes:
- Passive-receive only: For passive receive-only operation (like push Email). No return link is required at all.
- Fully interactive: For fully interactive service, the return link must be available during the whole session.
- Partly interactive transaction mode: For request-reply transaction services the link is only required for the transmission of the requests and can be released during the reply phase (for example the transmission of a large multimedia file). The return link can also be established with a 2 Mbps MDSA radio system.
MDS America Gigabeam Internet
At the MDSA MVDDS Hub
The basic Internet solution supplied by MDS America combines several of our components that are integrated with standard equipment:
The heart of the network, controlled by the MMDS MDSA MVDDS service provider, is the MVDDS MVDDS equipment. This equipment consists of the Internet Radio Server, combining network access and conversion to the DVB transport stream format. MDS equipment integrates with the conventional equipment while utilizing available standard DVB modules.
The Internet Radio Server consists of:
- MDSA MVDDS Internet Gateway
- MDSA MVDDS Access Server
- MDSA MVDDS Proxy Server
MDSA MVDDS Internet Gateway provides the connectivity between the network and the MMDS MDSA MVDDS Transmitter. On the input side the MDSA MVDDS Internet Gateway connects to the network via a LAN implementing 100BASE-TX Ethernet protocol. Its output is a standard DVB on either parallel LVDS or serial ASI interface. The MDSA MVDDS Internet Gateway is linked directly to a DVB modulator (in case of SCPC transmission) or alternatively to an optional DVB MUX which in turn connects to a DVB modulator (for MCPC transmissions).
At the subscriber end, an MDSA MVDDS modem and software will be deployed. It will typically have two connections: one to the antenna and the other to the computer.
The MDSA MVDDS Modem is a device that allows high-speed data access (such as to the Internet / Intranet) via the MDSA MVDDS terrestrial broadcasting system. MDS's modem allows consumers to access the Internet at a fraction of the time it takes traditional telephone modems network. More than 7 Mbps (875 Kbytes/sec) can be transferred for each FTP session.
The MDSA MVDDS Modem speed varies widely. In the downstream direction (from the network to the computer), speeds can be anywhere up to 52 Mbps. The return link (from computer to network) is provided via a normal PSTN, ISDN, GSM modem or possibly PCSP2, (wireless 2 Mbps radio modem), if available, depending on the application supported.
The MDSA MVDDS Modem sends and receives data in two slightly different fashions while benefiting from the nature and architecture of the broadcasting equipment and services.
In the downstream direction, the digital data is modulated and then placed on bandwidth available/allocated for this service by the MDSA MVDDS service provider (up to 52 Mbps).
The return channel is trickier and utilizes the currently available telephony modem (even a 1200 bps telephone connection is enough to receive the 52 Mbps Internet downstream).
To give a better idea of this kind of speed, consider the following example:
- The time a 25 Mb file takes to download will be:
- 30 Kbps modem connection = 140 minutes
- ISDN = 70 minutes
- T1 = 3 minutes
- MDSA MVDDS System = 30 seconds
- High Speed Internet Access (Radio and Modem ISP Configuration)
- The MDSA MVDDS operator provides modem Internet services or collaborates with specific ISPs to together provide fast Internet services. The existing equipment at the ISP is configured to re-route the IP packets to the MDSA MVDDS Internet Gateway station at the MDSA MVDDS Hub (Of course subscribers can still connect to the Local ISP in order to receive the high-speed network).
- High Speed Internet Access (Radio only ISP Configuration)
- The MDSA MVDDS operator does not provide any modem connection, only wireless high-speed access (up to 5 Gbps). The user keeps his usual modem ISP for the Requests packets. The subscriber can use any dynamic or static IP address. The subscriber can dial up to any local ISP, and receive the high-speed Internet via MDSA MVDDS.
MDSA MVDDS enables the typical array of Internet services to be delivered at speeds far faster than those offered through dial-up telephone modems. Other services may include access to streaming audio and video servers, broadcasting and multicasting of local (community information and services) as well as nation wide content sites, access to CD-ROM servers, and a wide variety of other offerings. New ideas like multi-participant net game services are being born daily.
- High-Speed Internet Access for Organizations
- MDSA MVDDS networks offer an attractive medium for providing low cost high-speed Internet/Intranet access for LAN users.
- High Speed Intranet Distribution
- Data Bank Services - Companies implementing their own private networks could establish new services or provide "on-line" services to their current customer base.
Potential Users and Real World Applications
The MDSA MVDDS's versatility, cost-effectiveness and quick implementation time make it very attractive to a number of potential users:
- ISPs (for high-speed backbone connection)
- Small to large organizations
- Schools equipped with computer classrooms
- Business centers and hotels providing Internet access as part of their services
- Planes, Boats, etc.
By using standard technology (which is also used for commercial Set-top boxes) and taking advantage of the high data rates available in the DVB - MPEG-2 system, a very favorable cost/performance ratio can be achieved. The current implementation can deliver data at a rate up to 60 Mbps.