Bromley Business Centre, 27 Hastings Road, Bromley, Kent BR2 8NA, UK

Core Network Engineer

4G/IMS Core
Experience: 10+ years
Knowledge in LTE/UMTS/GPRS with basic IMS knowledge.
Experience with Wireless Data Core networks, Architecture, Protocols and Interfaces.
Experience with LTE core system interfaces and protocols such as S1-MME, S1-U, S6a, S11, S5/S8, Rx, NAS, S1-AP, RRC, GTPv2c, GTP-U, SGs-AP.
Understanding of Rel 15 and Rel 16 3GPP standards
Working Experience in VoIP/IMS Core entities (Knowledge of P/I/S-CSCF, HSS, SLF) and VoLTE.
Extensive working experience with SIP Call processing and SIP Supplementary Services.
In-depth understanding of Telecom Protocols and technologies like SIP, SDP, H.248, MGCP, DIAMETER etc.
Expertise in creating test plans for system level, subsystem level and feature level testing.
Understanding of Software testing Life cycle.
Working knowledge in Automation testing using any framework
Good Knowledge in TCP/UDP, IP protocols and understanding of basic OSI model.
Knowledge of Database (Oracle, Informix, Microsoft SQL Server).

Core RCS
Engineer: 6 to 9 years
Working Experience in VoIP/IMS Core entities (Knowledge of P/I/S-CSCF, HSS, SLF) and VoLTE.
Work experience on RCS features as 3GPP releases like VoLTE, IPME, other RCS features
Extensive Working experience with SIP Call processing and SIP Supplementary Services.
In-depth understanding of Telecom Protocols and technologies like SIP, SDP, H.248, MGCP, DIAMETER etc.
Conceptual understanding of IMS evolution and trends – IMS Subsystems, functionalities and IMS SIP Services call flows.
Experience in TLS, TCP, IPSEC, IP protocols.
Experience in integrating/working with various components of a distributed next generation IP based architecture including soft switches, Gateways, SIP Proxies, Route Engines, IP Media Servers, IP Phones/IADs is a plus.
Working experience on IMS interworking entities (BGCF, MGCF, MRFC, MRFP, AGW, IBCF, TrGW) and interfaces.
Knowledge on Session Border Controller, NAT, Firewall, Authentication Encryption, L2 Layer switches (Routers/Switches).
Media handling, transcoding, call modeling CS, SMS, MMS and need to have knowledge on the MGWs.
Good Analytical and Log debugging Skills (Scripting knowledge is a value added)

5G Core
Experience: 12-16 years
Experience with Wireless Data Core networks, Architecture, Protocols and Interfaces.
Understanding of Rel 15 and Rel 16 3GPP standards
Knowledge in LTE/5G core architecture with IMS knowledge is desired.
Working experience on IMS interworking entities (BGCF, MGCF, MRFC, MRFP, AGW, IBCF, TrGW) and interfaces.
Knowledge on Session Border Controller, NAT, Firewall, Authentication Encryption, L2 Layer switches (Routers/Switches).
Experience with 5G core system interfaces and protocols.
Expertise in creating test plans for system level, subsystem level and feature level testing.
Good Knowledge in TCP/UDP, IP protocols and understanding of basic OSI model.
Knowledge of Database (Oracle, Informix, Microsoft SQL Server).
Experience in Customer facing role and resolving technical and handling Customer escalations.