5G Opensource Initiatives

When it comes into mobile core network, well-known open-source initiative is Open Air Interface Software Alliance (OSA) which released base station and core network software for 4G network. They are continuing their work on 5G also. However, when it comes to 5GCore network, more appealing work comes from Free5GC than OSA. This analysis is completely based on publicly available source code for 5GCore network functions. Another interesting open source network function is UPF which is built using Vector Packet Processing (VPP) by TravelPing.

Free5GC

On December, 2019, Free5GC, open-source project, released the stage 2 of their development on 5GCore network accommodating the service based interface of 5GCore network functions. Their reference design is as per the diagram and includes the following network functions: UPF, SMF, AMF, PCF, UDM, NRF, NSSF, AUSF and N3IWF. 3GPP Release 15 and Release 16 is basis of Free5GC development.

VPP based UPF

UPF, data plane entity, manages PDU session between access network and data network, based on the information received from SMF as combination of PDR,FAR, URR, QER, and BAR. UPF behaves a UP link classifier/branching point and session anchor.

VPP technology is open-source technology, provided by Cisco to build the higher performance data plane on commodity CPUs. The network packet processing is a directed graph of number of nodes in VPP. Each node processes vector of packets and forwards to another node. This graph is easily modifiable. Because of modularity and flexibility, new protocol can be implemented as a VPP plugin. VPP is a good candidate for building the UPF, because VPP has proven performance and production quality.

VPP does not have official support for UPF. However, TravelPing developed UPF plugin for VPP. This plugin supports 3GPP TS 23.214 and TS29.244 version 14.1. Many parts of PFCP protocol are implemented.

To understand more on the above topics, please do not hesitate to attend Telecontran’s workshops on following topics:

• Workshop on 5G Technology
• 5G and IoT Network design, Planning and Applications
• 5G New Radio (NR) Design and Planning
• 5G Core (5GC) Network