The recent major outage of that happened to Telenor Pakistan’s mobile communication network brings the service provider into focus on the need on its core network stability and resilience.
Across the country’s southern region, Telenor Pakistan’s fiber backbone network was interrupted in several areas, causing a widespread disconnection that shut down voice and data services for around five hours. For the duration of the outage, the operator notified its subscribers that its network was unavailable while repairs were being carried out. However, the operator was not able to confirm that its services had been completely restored until a full eight hours later.
This eight-hour network outage has had a significant impact on the operator’s reputation in Pakistan. While problems on the backbone network can generally be located and rectified quickly, after the network has been recovered, the instantaneous reconnection of tens of millions of subscribers has a huge signaling impact on the core network.
If the core network is unable withstand this impact, the network may be paralyzed across an even wider range – and this is exactly what happened as a result of this fault. After the backbone network was recovered, a core network signaling storm was triggered and a period of network downtime followed. In this instance, the core network appeared unable to withstand the signaling storm following the initial outage.
This is unfortunately an increasingly frequent occurrence. In the past few years, many of the major outages across the communications industry have been related to the core network.
In January 2021, a core network incident caused an 8-hour network outage for U Mobile Malaysia, while in May 2021 an outage caused by the Rogers core network in Canada resulted in 26 hours of downtime, severely affecting public safety as users were unable to place emergency calls.
In November 2021, Japanese operator NTT DoCoMo experienced a core network incident resulting in 29 hours of network paralysis, with the operator’s management forced to hold a press conference to make a public apology. Most recently, in December 2021, Orange France experienced a core network outage during which emergency calls failed.
The stability and reliability of the core network is a primary consideration for carriers when selecting their suppliers. The core network is the brain of the entire network, with the control plane deployed at its heart. This means that if a single fault occurs in the control plane a large number of incidents are likely to ensue across the entire network.
Moreover, as the development of 5G accelerates the requirements for stable and reliable core networks becomes even more critical. In addition to providing voice connections, 5G is also integrated with the real economy to promote the development through IoT and toB applications, with the technology running through the production and operation of thousands of industries. As a result, network status impacts not only basic calling, but also the development across thousands of industries.
According to the latest data from GSMA Intelligence, 200 5G networks are expected to be commercially deployed in 70 countries and regions by the end of 2022, with the number of 5G connections worldwide reaching 640 million.
In recent years, network accidents caused by core networks have become more frequent in the communications industry, triggering a rethink of best practice across the entire industry. Core network cloudification has undergone a process from virtualization to cloud native. Currently, leading carriers around the world have chosen cloud native as the basis for next-generation 5G core networks. At the same time, industry-leading equipment vendors, such as Ericsson, Huawei, and Nokia, have jointly chosen cloud native technology as the key technology foundation for enabling the next-generation 5G core network.
Carrier-class reliability is the biggest challenge throughout the entire cloud transformation process. The increasingly flexible cloud architecture brings great challenges to vendors’ reliability, architecture design, resilience to signaling storms, and uninterrupted service switchover based on data center architecture.
To ensure that carriers can continuously deliver high-quality services to customers in the cloud era, building a reliable, agile, and resilient core network is the top priority. This requires the cloud-native core network to have a highly reliable architecture design, extreme agility and automation capabilities, and data centre-level service switchover. Therefore, the traditional carrier-class reliability of ‘five nines’ is now being built on the basis of ‘three nines’.
All global mainstream vendors are actively investing in 5G core network architecture design innovation, but they still have a gap in competitiveness. According to the 5G Mobile Core: Competitive Landscape Assessment released in late 2021 by GlobalData, an authoritative consulting firm in the global ICT field, Cisco, Ericsson, Nokia, and ZTE are all rated Very Strong while Huawei achieved Leader status.
Source: GlobalData “5G Mobile Core: Competitive Landscape Assessment”
Considering the increased occurrence of communications outages in recent years, it is clear that further investment is still needed to achieve the highest standards of network stability and reliability for operators. As 5G networks become dominant, connecting trillions of devices and serving thousands of industries, core network stability and resilience will become key.
To improve the stability and reliability of the core network, operators and vendors must work together to continuously improve and optimize technologies and talent development to solve problems in cloud native evolution and achieve digital transformation of the entire industry.