Our systems have detected unusual traffic from your computer network

[WallyWest]

I get this message from time to time when I do a Google search:
----
Our systems have detected unusual traffic from your computer network. This page checks to see if it's really you sending the requests, and not a robot. Why did this happen?----
Then it leads me to a captcha page.It's not just Google. I sometimes get a similar error while browsing Lazada and rarbgmirrored.org.
I regularly check my computer for malware although I don't check my family's PCs and gadgets and none of them have complained either. Could this be a problem with one of the users of my home network or is it a problem with my ISP? I'm on Converge by the way.

[jeremypv]

if you have your own external IP, then maybe you are hosting a malware on your PC.

if you have a CGNAT connection (all LTE broadband, and Converge, and PLDT is rolling this out since 2years ago), then this is normal as there are many people using the same external IP. e.g. when people login, google sees the same IP with so many login attempts

for rarbg, this is just their strict implementation of anti-robot filter, whenever it encounters an IP address for the first time with an IP/browser/id combination it will check on you with a captcha -- kind of annoying for me when I first boot-up my PC and go to rarbg, because first it will access rarbg with an IPv4 address, then will captcha me, when the IPv6 kicked in, it will again captcha me saying that my IP is an IPv6 address now.

[WallyWest]

^Thanks for that clear explanation. Nope, I do not have a public IP.

It is annoying when I have to do a captcha maybe twice in a day. Although I do notice that if I switch browsers the warning no longer shows up on the new browser instance. Or I just wait it out and access again after a minute or less.