What is the effect of default user session limit in N-4100 (Hotspot) and how/when to adjust it?

Model Number: ZyXEL N-4100

Problem 

Sometimes network traffic drop constantly or even unable to access website while browsing, no matter from LAN or WLAN

Solution

It is caused by default user session limit of N4100, which is 128

You can adjust it according to your network utilization policy to match specific needs

Said symptom is that N4100 has running out of sessions, the ping ICMP packets will not get response from 8.8.8.8.

If similiar phenomenon happens, please adjust user session, it can ease the symptom

Procedure

The N4100 is at factory default setting

GW------------------N4100---------[Ethernet or WLAN]----------------PC

To browse websites and ping 8.8.8.8 at the same time, found ping lost very often while doing quick web browse
(switch website before page completely loading)

I can see ping loss and web page loading fail very often, sometimes the website will even become unavailable.

To ease the symptom you just need to idle the device for a moment