Strict nat on Airtel ZTE f670L router

[rxuser]

Hello I have been having issues while directly communicating with devices using zerotier and from the diagnostics I did, I found that airtel is running on symmetric nat which I tested using this NAT Test: Am I behind a Symmetric or Normal NAT?

This hinders p2p connectivity using zerotier, so is there a way to get a normal nat instead of this ?? I am using ZTE f670l ont provided by them and have enabled upnp and dmz but the status is the same

 

[rxuser]

Here is the trick they do based on whether you are checking the NAT type in applications.
Endpoint Independent Mapping is full cone/normal nat and Address and Port Dependent Mapping is Symmetric NAT

 

[rohitks]

As I mentioned you will have to write to net@airtel.com and specifically ask for interaction with networking backend expert to manages their network, not field engg. That's what I did when I wanted router with Bridge mode support. It's frustrating, initially they don't understand your requirement but you insist to talk to expert and eventually may get connected to one thru one of their field engg.

also check if you switch to static ip can solve the issue bcos then as i tested dmz/upnp should work i suppose

 

[Harmanpreet]

they charge for static ip and only one who have postpaid connection receives it,so even if the problem is of cgnat,they will not give public ip for free and even the servers,routers,ont they configured are just weirdly configured like when first day i got the connection,i got public ip but then next day it changed to private ip in router wan,even when you try to do tracert,the server that is actually next to your router doesnt appear which might be the main cause of the problem,it might be due to pppoe.MTU rate is also 1480-1492,so i think the way airtel configured their devices are actually for the dsl connections but they just upgraded base stuff and the configuration remained same.Their network engineers can actually fix this problem by just a simple command but i think the conversation of problem never reaches to them as local technician never tries to call backend or to inform higher team

 

[rxuser]

That's bad that they don't even provide static ip for prepaid customers to solve this although a configuration change on their end will fix a lot.

 

[theOne235]

Same issue is with tata play fiber. Only port 3478 & 3479 replies with full cone NAT, otherwise its symmetric.
Any solution found or any reason found for this?