DAMA/ABOD for bandwidth QoS plays a significant role in reducing bandwidth usage while achieving high performance. SkySwitch’s DAMA/ABOD capability provides dynamic Bandwidth-On-Demand adjustment in real-time to hub traffic data carrier(s) and every remote terminal's carrier. DAMA/ABOD operation responds to traffic demand. Its intelligence and execution are provided by each remote terminal. The process always follow network bandwidth management policy.
DAMA operation activates carrier upon presence of data traffic. When there is no data traffic from a site, DAMA process turns of its carrier to save bandwidth. This means DAMA carrier does not use any bandwidth when it is deactivated due to no data traffic.
ABOD operation provides just in-time bandwidth as needed for the exact duration as required by a terminal to forward its own traffic while avoiding traffic congestion. CIR (committed Information Rate) further provides guaranteed rate for each terminal or a group of terminals. When a large number of remote terminals of multiple groups and subnets are pooled together to share a large bandwidth segment, savings on bandwidth is substantial.
SatPath engineers are the first in the VSAT industry to design and deploy a fully automatic DAMA/BOD technology back in 1990’s. Since then the BOD technology has been adopted by other suppliers under different names. Continuous refinement of the technology over 20 years leads to the most efficient Adaptive-Bandwidth-On-Demand (ABOD) capability in SkySwitch. When ABOD combined with the On-Demand DAMA operation, network users experience the most satisfying services with instantaneous carrier rate change and minimum latency. Most importantly, ABOD is designed to reduce bandwidth usage and not so much about how often a carrier is changed. It is misunderstood that frequent changing bandwidth is a good thing. ABOD algorithm streamlines fluctuating and bursty traffic into steady flow that effectively reduces bandwidth while maintaining stable connections. ABOD converts short term high and low data flow to a steady flow, which can be adjusted from time to time as needed by overall traffic volume. Steady carrier rate can save bandwidth as much as 60%, while provide more reliable link quality.
ABOD as a QoS process also supports user configured bandwidth allocation priority. 6 levels of priority can be assigned to each site. Each site's use of bandwidth can be protected during congestion or expanded when unoccupied bandwidth become available.
ABOD adjusts carrier rates in real time based on actual traffic flow without fixed preset time-step or rate-step. A bandwidth defregmentation process runs at the background to collect and consolidate unused bandwidth segments at all time. Overall bandwidth usage follows Bandwidth QoS policy set by network operator. The operation uses a shared Network bandwidth pool, which can be changed, reduce or expand, on the fly without any impact to existing on-going connections. Such capability to instantaneously changing available transponder bandwidth resouce is critical for Emergency Response network.
IP traffic is always multi-media over a common IP link. Standard IP QoS protocols are designed to priotizing IP traffic. SkySwitch IP QoS capabilities include prioritizing traffic based on its service levels depending on protocols and services. ToS and more comprehensive DSCP protocols are supported througout the network. QoS operation is balanced by fairness algorithm and protocols, as well as user specified priority levels so that each IP packet gets its chance to be further forwarded even in congested situation occurs during busy hours.