Sani faults Odinma on congestion

The Director, Technical Standards and Network Integrity at the Nigerian Communications Commission (NCC), Dr. Balarabe Mohammed Sani has disagreed with the position of Prof. Augustine Odinma on the congestion in mobile networks in the country.

Reacting to a recent publication attributed to Prof. Odinma, Dr. Sani said that it is a widely acknowledged fact that there are serious issues of quality of services on Nigerian telecommunications networks and the NCC has taken up the challenge by daily interfacing with the operators on these issues.

The Commission, he noted that recently introduced new Key Performance Indicators (KPIs) to measure the quality of service offered by the operators and is sanctioning those who fail to meet the quality threshold.

Prof. Odinma was quoted as saying that on congestion “in mobile networks is subjective, unprofessional and baseless because of lack of the use of conventional techniques of testing quality of service (QoS) on mobile networks.”

According to Dr. Sani a trained engineer, any statistical method as the Prof. knows, the data sample size is very important in ascertaining the correct result. “The more we increase the number of data samples, the more correct the statistical result,” he said.

He disagreed with Odinma’s claim to have enough samples for the evaluation, Sani noted that Odinma had claimed that about 72,334 calls were made during the test within six days period from three fixed locations in Lagos, Yola and Abuja. That was an average of 12,000 calls a day.

“If we study the modern network performance testing methods, we find out it will not be possible to make 12,000 calls in a day in the manual testing method claimed by the professor,” he said.

Sani recalled that automated equipment test several GSM networks at the same time in one time slot.

“A manual testing can only test one handset at a time and therefore would be impractical to have up to 12,000 samples per day even if the test will be extended to 24 hours,” he said.

On the lack of considering mobility management function of mobile network, Dr. Sani pointed out that Odinma and his co-researchers had forgotten a major aspect of mobile technology in their experimental research, that is, mobility management.

“Mobility management is an important phenomenon that distinguishes mobile technology from fixed network,” he declared, saying that a network has the capability of seamlessly handing over an ongoing call by a mobile user to a neighboring cell in a process called handover.

“If signal strength degrades to some level in the serving cell, six neighbouring cells are tested by the network and the one with better signal strength is selected. A stationary user as claimed by the Professor in his research does not consider the mobility aspect of the mobile network,” Sani said.

He argued that a stationary user as in the case of professor’s testing methodology may experience congestion because he is hooked to only one cell called serving cell that may have weaker signal or traffic congestion at some instant.

Odinma’s team, he further said, could have been testing from only single cell from the three different locations, which does not test the performance of mobile network as a whole, because large number (thousands cells precisely) of cells make the complete network. For the professor’s test to be meaningful he must move to test as many more cells as possible.

As said by him, another thing the professor failed to take into consideration is the bouncing busy hour on a mobile network, which he said, is unlike a fixed telephone network.

“… In a mobile network the busy hour is not fixed, it is dynamic over time,” he said.

Dr. Sani cited an instance by saying that the mobile user who lives in Victoria Island (VI) in Lagos may experience high congestion during working hours and less congestion in the evening and weekends.

This, he explained, is because in the evening and weekends more people have moved out of VI.

“The people who live near market places may also experience similar phenomenon,” he said.

The failure by Odinma’s team to consider the bouncing busy hour phenomenon in a mobile network environment by conducting test from three fixed locations, Dr. Sani said, led to erroneous results since mobile environment was regarded in the experiment to be similar to a fixed network environment.

“Lack of inclusion of the mobility management aspect of the mobile network technology in his test leads us to believe that the Professor has a limited knowledge of the mobile network QoS testing methodology,” he submitted.

Remmy Nweke:
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