Zyxel NR 5103E - Functions QoS , DDNS & VPN ? And more .

My question is about why this Zyxel router 5103E dont have any of thoose functions .

Maybee it is same with 7103 . But that i dont have any manual for so i can tell anything about features on that one.

Is it a hardware or software limitations that this functions not exist ?

Or is just hidden features that Zyxel or the Operators dont want their costumers to use .

Same with that NR 7101 Thoose have theese functions. : DDNS , VoLTE ,VoiP but not vpn.

And may it bee some functions coming in future firmware update .

On 5103E i have this VMM QoS . But seems like a light one . Nothing much to do than on or off. And only prio for video . No other choice.

"WMM QoS ( MultiMedia Quality
of Service) gives high priority to video, which makes them run more smoothly."

Also saw that VoLTE and VoiP added . But i have Wi-FI call so maybe it have changed since this manual got written ?

And if have "VoiP" ,Why should i need "VoLTE" function also ? Call over wi-fi broadband . That have LTE connection and then call over "LTE" ?

Best Regards F