How to Build Virtual Networks with NFV: VLAN, VPN, vRouter, and vFirewall Code Samples

NFV (Network Function Virtualization) decouples network functions from physical devices and implements them as software that runs on standard servers as virtual machines, containers, or lightweight processes, enabling flexible deployment and elastic scaling.

The main virtual network types in NFV are:

Virtual LAN (VLAN) : divides a LAN into virtual logical segments. Example in Python:

class VLAN:
    def __init__(self, vlan_id):
        self.vlan_id = vlan_id

    def create_vlan(self):
        # code to create virtual VLAN
        pass

# Create a VLAN instance with ID 100
vlan = VLAN(100)
vlan.create_vlan()

Virtual Private Network (VPN) : provides secure remote access over public networks. Example in Java:

public class VPN {
    private String vpnName;

    public VPN(String vpnName) {
        this.vpnName = vpnName;
    }

    public void createVPN() {
        // code to create virtual VPN
    }
}

// Create a VPN instance named "my_vpn"
VPN vpn = new VPN("my_vpn");
vpn.createVPN();

Virtual Router (vRouter) : software instance that performs routing in a virtualized environment. Example in Go:

package main

type vRouter struct {
    routerID string
}

func (vr *vRouter) createRouter() {
    // code to create virtual router
}

// Create a vRouter instance with ID "router1"
vr := &vRouter{routerID: "router1"}
vr.createRouter()

Virtual Firewall (vFirewall) : software instance providing network security functions. Example in C++:

class vFirewall {
private:
    std::string firewallName;
public:
    vFirewall(std::string firewallName) {
        this->firewallName = firewallName;
    }

    void createFirewall() {
        // code to create virtual firewall
    }
};

// Create a vFirewall instance named "my_firewall"
vFirewall firewall("my_firewall");
firewall.createFirewall();

Using NFV, these virtual network components can be deployed flexibly and scaled elastically, greatly simplifying network architecture.