Here’s why MTN Nigeria’s service went down

The network disruption experienced by over 73 million subscribers on the MTN Nigeria network on Saturday was caused by a disruption in the core network affecting voice and data services, the company said in a statement.

MTN Nigeria said its technical team was able to rectify the problem in about five hours, allowing service restoration for customers to begin connecting with one another. The company is also extending time-bound subscriptions to ensure full value is delivered to all affected customers.

“I want to apologize to all the customers that were affected by Saturday’s service outage. Our primary mission is to bring you the benefits of modern connected life, and notwithstanding this unfortunate event, our commitment to providing the reliable service you’ve come to expect over the past twenty years remains unshaken,” Olatokun Toriola, CEO of MTN Nigeria said.

Core network in the telecommunications industry refers to a central element of a network that provides services to customers who are connected by the access network. The core network is responsible for a number of services including routing telephone calls across public switched telephone network (PSTN). This allows mobile subscribers to get access to the services that they are entitled to use. The mobile core network also provides critical functions such as subscriber profile information, subscriber location, authentication of services, and the necessary switching functions for voice and data sessions.

Read also: MTN Nigeria users experience hours of network disruption

Routers and switches are the facilities and devices used for the core or backbone network. Switches are used more often. The technologies used for the core facilities are mainly network and data link layer technologies, including asynchronous transfer mode (ATM), IP, synchronous optical networking (SONET), and dense wavelength division multiplexing (DWDM). For backbone networks used for enterprises, a 10 GB Ethernet or gigabit Ethernet technology is also used in many instances.

The mobile core network has evolved considerably from 2G, 3G to 4G. The core network for 2G GSM used to be known as Network Switching System (NSS). later the General Packet Radio Service (GPRS) was introduced resulting in two nodes, Serving GPRS Support Node (SGSN) and Gateway GPRS Support Node (GGSN) serving as part of the 2G core network.

The same approach was followed for 3G Universal Mobile Telecommunication System (UMTS) core networks. 4G LTE networks (Long Term Evolution), however, use a more advanced core network called Evolved Packet Core or the EPC.

Over the years, disruptions brought about by problems arising in the core network have affected 2G, 3G, and 4G networks. For MTN, Toriola says the company is working closely with network partners Ericsson and Cisco to ensure that the reasons for the disruption are fully investigated, and appropriate action is taken to enhance the resilience of affected systems.