# Cloud-Enabled Deployment of 5G Core Network with Analytics Features
## 4 The Testbed
### Setup Parameters and Networking  
The parameters of the setup and the networking configuration are crucial components of the testbed proposed in our work. The solutions presented in this section should be regarded as a solid foundation for establishing a research environment focused on cloud-based 5G core deployments.  
The testbed for the deployment of the 5G network (5 GCN + 5 GAN) via VirtualBox is based on a personal laptop. Its physical parameters are listed in Table 1. The virtual machines deployed under VirtualBox have the following roles assigned:  
* \(\quad\)vm_5 GC-CP hosts the CP NFs.
* \(\quad\)vm_5 GC-UPF hosts 5 GC UP functions.
* \(\quad\)vm_5G-UERANSIM hosts the 5 GAN together with UEs.  
The configuration of these VMs is presented in Table 2. To accommodate more NFs deployed on **vm_5 GC-CP** compared to the other VMs, its physical resources (i.e., RAM) have been doubled. Each VM has been equipped with the 64-bit version of _Debian 11 Bullseye_ OS.  
When a VM generates outbound traffic, the NAT adapter of the hypervisor's NAT engine extracts the TCP/IP data and forwards it through the host operating system to a remote network (e.g., the internet). Networking between VM-VNFs is managed by the VirtualBox internal switch (_Oracle VM VirtualBox networking engine_[37]), which ensures connectivity between the VMs and the host platform. Each VM is equipped with three network adapters.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**CPU** & 1.4 GHz Quad-Core Intel Core i5 Turbo Boost up to 3.9 GHz \\ \hline
**GPU** & Intel Iris Plus Graphics 645 1536 MB \\ \hline
**Disk Size** & 128 GB SSD \\ \hline
**RAM** & 8 GB 2133 MHz LPDDR3 \\ \hline
**Operating System** & macOS Monterey \\ \hline \hline \end{tabular}
\end{table}
Table 1: VirtualBox host platform: Apple MacBook Pro 13-inch originating from Germany (2019) specification.  
Figure 2: Virtualized 5G Core Network with slice-dedicated NFs.  
The first adapter, labeled as _enp0s3_ for Debian distributions, is configured as a NAT adapter to enable internet access from within the virtual machine. This NAT interface serves as the default gateway device. The IP address of the NAT interface in the guest VM is bound to the loopback interface of the host OS, acquired from the hypervisor's DHCP engine, and resides within a NAT address pool (10.0.2.0/24). The remaining two interfaces of each VM are configured as _host-only networking_ type, which is easily reproducible in a cloud environment.  
The network space created within VirtualBox is logically divided to reflect the responsibilities of each part and ensure data separation. Two virtual interfaces created by VirtualBox on the host platform correspond to the logical network space summarized in Table 3.  
Interfaces of each of the VMs, named _enp0s8_ and _enp0s9_, are assigned to one networking space. Interface _enp0s8_ is attached to a _northbound networking space_ and is used by the host platform to remotely configure the NFs on the VM. _Enp0s9_ binds to the _data networking space_, in which all 5 GC and 5 GAN traffic is handled. The OS of _vm_5 GCN-UPF_, which hosts the 5G CP functions, must support Network Address Port Translation (NAPT) to enable data tunneling to an outbound network. Furthermore, it must support IPv4 forwarding and be equipped with TUN interfaces for each of the PDU sessions [41].