Routed Multi-destination Network (RMD)

RMD is a network architecture that uses IP multiplexing to aggregate outbound traffic at the hub, so that the hub can transmit a single outbound carrier that is received by all sites in its network or sub-network. .RMD graphic By aggregating all IP transmit streams into one carrier, statistical multiplexing gains achieved by averaging out peak and valley traffic of multiple IP streams realizes bandwidth savings.

RMD has proven to be a highly efficient and flexible IP transport methodology for star, partial mesh, and full mesh network architectures. In a star network environment, RMD consists of a single aggregate outbound carrier transmitted from the hub, and multiple SCPC inbound carriers from the remote sites. IP packets are dynamically routed in the RMD network busing well known protocols such as OSPF and BGP. Use of these routing protocols in conjunction with LinkCast, a unique dynamic routing address scheme, allows efficient transport and highly effective packet filtering at each site. Packet prioritization can easily be configured using the native differentiated services and QoS capabilities of the router.

Due to the statistical multiplexing done on the individual IP streams into a single stream, further bandwidth savings can be realized by oversubscribing the outbound circuits.  In a typical SCPC network, each carrier is sized to accommodate the peak traffic for that route.  Bandwidth gains are realized by aggregating traffic and averaging out the individual fluctuations in traffic demand for each site.  During traffic spikes, lower priority packets can be queued up by the LinkIP so that the circuit does not have to be sized for the absolute peak traffic periods.  RMD graphicThis “oversubscription” allows a reduction in size of the outbound carrier without noticeably impacting overall network performance.  Each remote site receives the aggregate outbound traffic, and the LinkIP router at each site filters packets, dynamically routing those packets destined for its local network, and discarding the rest.

The inbound channels from the remote sites are discrete SCPC carriers. These inbound channels can use existing modem equipment. Addition of single hop remote to remote links for partial mesh capabilities within the RMD architecture is just a matter of adding another demodulator to each remote that wants to have a single hop connection to another remote. The additional demodulator would be tuned to the outbound carrier of the remote site to which it wants to connect. If remote 1 wants to establish a single hop link to remote 2, for example, both sites would add a demodulator. Remote 1 would tune the new demodulator to remote 2's transmit frequency, and remote 2 would tune its new demodulator to remote 1's transmit frequency.