Connecting to Multiple Networks with Multus

Depending on requirements, SBA Gateway might require a dedicated connection to the 5G network separate from its connection to other MATRIXX components.

Kubernetes by default only provides a single network interface on each pod. Pods cannot attach to more than one network. When the 5G network and the operations and maintenance (O&M) network are isolated from each other, and SBA Gateway initiates an NRF registration request, the default Kubernetes container network interface (CNI) makes this request on the O&M network, having no access to the 5G core. Service meshes or Kubernetes CNI plug-ins, such as Multus, can give SBA Gateway separate network connections for both networks.

Note: Multus is one of several CNIs and service mesh solutions that allow pods to have more than one network interface. Alternatives to Multus are available.

Figure 1 shows the following:

  • Incoming traffic from the SMF/PCF going to SBA Gateway through a load balancer.
  • Outgoing traffic directly from SBA Gateway.
  • Traffic to/from 5G network functions on a separate network from the network carrying inter-pod communication with the Charging Server.
Figure 1. Separate Signalling and O&M Networks
Separate Signalling and O&M Networks
Note: For information about how to install and enable Multus, refer to the Multus documentation.