SLAC monitors 4 sites in Bangladesh. They are seen below in the map.
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The ping Round Trip Times (RTTs) are seen below. We observe:
More detail for the Daffodil site are seen below:
The route from SLAC to Daffodil International University goes from SLAC to Palo Alto (3 miles away), to New York, London, Paris, Mumbai and Bangladesh.
The route to BRAC is similar.
The routes from SLAC to DUET and RU goes from SLAC and the San Francisco Bay Area to Dallas, Palermo Italy and thence to Bangladesh
The column labeled BD below are the measurements of the various metrics made to other regions of the world from Daffodil International University for October 2014. Information on the meanings of the metrics can be found in the tutorial at http://www.slac.stanford.edu/comp/net/wan-mon/tutorial.html.
Derived_throughput = MSS /(RTT*sqrt(loss))
where MSS = Maximum Segment Size typically = 1460Bytes.
This mainly a function of the route length between the source and destination.
This is typically an edge effect.
This mainly a measure of the route length between the source and destination. All regions are reachable by terrestrial routes (i.e. no minimum RTT > 400ms).
Looking at the long term minimum RTT from SLAC to Bangladesh seen below it is apparent that the connection switched from using geostationary satellites (>450ms) to terrestrial connections (< 450ms) in 2006.
Looking in more detail at the minimum RTTs from SLAC to Bangladesh see the plot below showing the cut-over for the RU university on 11 October 2006 around 7:00am UDT. The spreadsheet is here.
If none of the pings sent each half hour respond then the target remote host is deemed unreachable. The plot below shows the monthly unreachability seen from SLAC to Bangladeshi hosts.
This is typically an edge effect.
This is a function of the average RTT, the packet loss and the jitter. It indicates how god a phone call is expted to be. Typically with MOS values above say 3.6 calls become acceptable. Thus VoIP calls should be of acceptable via the Internet between Daffodil International University and the regions in yelolw and green in the table below.
How direct the route is between a source (monitor) and destination (monitored/remote) site is given by the directivity index. A value of 1.0 indicates that the route is a great circle route between the sites. Smaller values indicate the route is less direct. It is seen that the routes between Daffodil International University and North America and Latin America are the most direct with values of 0.42 and 0.45. Other routes are more indirect, with the route to South Asia being the least direct.
Looking in a bit more detail at the connections between Daffodil International University and S. Asia we find:
These are shown from between Daffodil International University hosts and from Daffodil International University to Duet.
The RTTs from pinger to www at Daffodil International University show that the Daffodil International University monitor pretty stable.
The distance as crow flies between pinger.daffodilvarsity.edu.bd and www.duet.ac.bd = 189.2 km. or a minimum RTT (as constrained by speed of light in fibre) = 1.892. the average minimum RTT from Daffodil International University to Duet is 2.55msec. This corresponds to a Directivity of 0.74, i.e. the route is pretty direct. The spreadsheet of the data from which the plots below were derived is here. The variability of the RTTs is much greater than that between hosts at the Daffodil International University site (first plot). Thus most of the variability is attributed to the route between Daffodil International University and Duet and possibly the host at Duet.
