Customer Network Support Engineer

At Ericsson, we are seeking a knowledgeable and dedicated Support Engineer to join a small IMS support team within MOAI NEO, focused on 5G Core and Cloud Core for NACI customers. In this pivotal role, you will own complex L2/L3 incidents, improve live network stability, and work closely with product, project and problem management teams to reduce outages, prevent repeat faults and introduce new CCxx releases safely. You will play a key role in delivering reliable, high-performing 5G Cloud Core solutions, ensuring customer satisfaction, operational excellence and ongoing service stability.

Responsibilities

Lead investigations and drive the resolution of complex L2/L3 incidents across IMS, 5G Core and Cloud Core environments; Restore customer networks and services during critical incidents, taking ownership of fault isolation, advanced troubleshooting and service recovery; Analyse system behaviour, identify root causes and work with problem management to prevent repeat faults and improve live network stability; Collaborate with product, project and delivery teams to support safe introduction of new CCxx releases and operational changes; Communicate clearly with customers and internal stakeholders during high-pressure incidents, providing timely updates and practical technical guidance; Drive operational efficiencies through automation, knowledge sharing, mentoring and continuous improvement; Independently manage support cases, resolve critical issues without escalation where possible, and contribute to reduced turnaround times.

Requirements

Strong understanding of IMS architecture and call flows, including P/I/S-CSCF, BGCF, MGCF, SBC, TAS/MMTel, HSS/UDM, PCRF/PCF, AS and related network functions; Knowledge of VoLTE, VoWiFi and VoBB fundamentals, including registration, originating and terminating calls, supplementary services, SMS over IMS, emergency calls, interconnect and roaming scenarios; Familiarity with vendor-specific IMS implementations and common deployment topologies; SIP and SDP expertise, including method types, dialogs, routing, forking, error codes, re-INVITE and UPDATE; Diameter knowledge across Cx, Sh, Ro, Rx, Gy/Gx interfaces, with exposure to Radius where applicable; Solid IP networking capability, including IPv4/IPv6, routing, VLANs, DNS/ENUM, NAT, firewalls, load balancers and QoS; Understanding of TLS/IPSec, certificates and basic security concepts for signaling and media; Linux administration skills, including system, networking, storage and performance basics; Experience with virtualization and cloud/NFVI concepts, including VMs, OpenStack, VMware and increasingly containers/Kubernetes for cloud-native IMS; Proficiency with tracing and analysis tools such as tcpdump, Wireshark, vendor trace tools, log parsing, KPI/alarm monitoring, NMS/EMS, Grafana, Prometheus or equivalent platforms; Scripting and automation capability using bash, Python, Ansible or similar tools for log extraction, health checks and repetitive operational tasks; End-to-end troubleshooting mindset, with the ability to correlate alarms, logs, traces and KPIs to isolate root cause.