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The growth in the number of monitors and host pairs being monitored over 2010, is seen below (spreadsheet):
!pak-infra-2010.jpg|border=1!
Map of sites
The locations of the Pakistani monitoring (red) and remote(red and blue) hosts are seen in the maps below.
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Using PingER, the monitoring hosts ping each remote host with 10 pings every 30 minutes. From this data we are able to measure minimum and average Round Trip Times (RTT), jitter, loss, unreachabilty (all 10 pings fail) and derive throughput and Mean Opinion Score (MOS). The data is gathered from the monitoring sites on a daily basis by the archiving sites at NUST, SLAC and FNAL.
RTT and Losses for 2010
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| Various percentiles for the Inter Packet Delay Variation (IPDV or jitter) between Pakistani monitoring hosts and remote host pairs. The line shows the number of pairs with measurements contributing to the results. Spreadsheet | The blue dots are the median losses seen between all pairs of monitoring and remote hosts for each month. The error bars show the extent of the 25 and 75 percentiles. The red dots are the number of pairs contributing to the packet loss measurements. Spreadsheet |
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To try and show the network performance trends within Pakistan in 2010 Amber created a graph showing the inter-regional average RTT performance over the whole year.
Results
Unreachability
A host is considered unreachable if none of the pings sent to it are responded to. To illustrate this we chose a reliable host at SLAC (pinger.slac.stanford.edu) and analyzed the unreachability of Pakistani hosts seen from SLAC.
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Table of unreachability seen from SLAC to Pakistani hosts in 2010. Higher values (bad) are colored redder. The data is sorted by increasing unreachability in Jan 2011. [Spreadshee | IEPM:Pakistan^pak-unreach.xlsx]t | Chart of the unreachability of Pakistani hosts seen from SLAC Dec 2010 and Jan 2011 | Smokeping examples of unreachabilltyseen from SLAC for 120 days Oct 2010 - Jan 2011. |
It is seen that several hosts exhibit high unreachability. The reasons behind the high unreliability are usually site specific and vary from lack of reliable power and a source of backup power, floods, lack of access to the site when there are problems that require physical access, lack of expertise, and lack of interest from a site.
Mean Opinion Score (MOS)
The telecommunications industry uses the Mean Opinion Score (MOS) as a voice quality metric. The values of the MOS are: 1= bad; 2=poor; 3=fair; 4=good; 5=excellent. A typical range for Voice over IP is 3.5 to 4.2 (see VoIPtroubleshooter.com). In reality, even a perfect connection is impacted by the compression algorithms of the codec, so the highest score most codecs can achieve is in the 4.2 to 4.4 range. Using the RTT, loss and jitter we derive the MOS.
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Median MOS and Inter Quartile Range (IQR) between Pakistani hosts for 2010. Spreadsheet | MOS between regions for Pakistani hosts. | MOS for fixed set of Pakistani hosts by region |
RTT and Losses for 2010
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|---|---|---|---|
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| Various percentiles for the Inter Packet Delay Variation (IPDV or jitter) between Pakistani monitoring hosts and remote host pairs. The line shows the number of pairs with measurements contributing to the results. Spreadsheet | The blue dots are the median losses seen between all pairs of monitoring and remote hosts for each month. The error bars show the extent of the 25 and 75 percentiles. The red dots are the number of pairs contributing to the packet loss measurements. Spreadsheet |
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To try and show the network performance trends within Pakistan in 2010 Amber created a graph showing the inter-regional average RTT performance over the whole year.
Understanding the large variations Jan-Apr 2010
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