Routing to own WAN address. AC-68P vs AC-88U

[DTM]

I have a Blue Iris camera server on a computer in my network. It is directly accessible via http://192.168.1.45:9000. It is accessible over the web via an Asus DDNS address: http://notdisclosed.asuscomm.com:9000 (this returns my WAN address of course)

I recently switched my main router from an AC-68p to an AC-88U. Note that I have slow Internet with 6M down and 768K up. I have my cameras set for 10 frames/second rate.

Over my local network with either router accessing the direct (192.168.1.45:9000) address I get the full 10 fps image.
If I am remote and truly over the Internet using the DDNS I get about 5 fps max.

With the AC-68P over my local network using the DDNS address I still get the full 10 fps. Using the AC-88U router I only get 5 fps just as if I was remote.

It appears to me that the AC-68P is smart enough to route my browsing computer directly to my camera computer even though I am using the DDNS (WAN) address. The AC-88U on the other hand appears to be routing over the Internet and gets the speed limited to my Internet upload speed.
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Now this isn't a major thing but it is a curiosity to me. How is it that the AC-66P knows to route directly and not use the WAN while the AC-88U apparently doesn't? Is there a setting I am missing on the new router?

 

[ColinTaylor]

Are you using QoS on the RT-AC88U?

 

[DTM]

Are you using QoS on the RT-AC88U?

Yes. I have tried it with QoS turned off though and it made no difference.

 

[eibgrad]

Presumably both routers are using NAT loopback, and thus neither should have an advantage over the other. In either case, the client's reference to the WAN ip makes it to the router, which then thanks to the DNAT of the port forwarded, is redirected back into the local network and the target. The replies are forced back to the router w/ SNAT, then finally back to the client. At no time is there a "direct" path between the client and target on the local network unless the client specifically addresses the target by its local IP. Not unless there's something on that client that's directing the DDNS domain name to the target's local IP (e.g., a local hosts file).

IOW, the path of access w/ NAT loopback should be exactly the same for both routers. I can't see how either router could have the ability to be "smarter" than the other.

 

[DTM]

Wow. Well I won't claim to understand all of that detail but I will say that I didn't expect there to be any difference in the two routers either. They are both running the latest Merlin firmware. When browsing with the DDNS address the 68P yeilds 10 fps and the 88U yeilds 5 fps. If you browse with the direct address they both provide 10 fps. Something different must be happening.

I would like to do both local and remote browsing of my cameras using the ddns address so when I carry the laptop on the road I don't have to switch. With the 68P that was not an issue.

 

[eibgrad]

Is it possible it's the client or target that have changed? If both are using the same wireless freq/channel (putting mimo aside for the moment), that is only half-duplex, meaning only one can transmit/receive at a time, effectively cutting the throughput in half. I'm just wondering if perhaps when using the RT-AC68U one or the other was wired, and now you're erroneously assigning the difference to a change in routers.

 

[DTM]

The camera computer is wired to the router and always has been. The browser computer is using 5G wi-fi from router. Just as a test after reading your reply, I turned off the wi-fi on my browser computer which is a laptop, carried it to the router and plugged it in with a cable. No change....: I get 10 fps on the 192... address and 5 fps on the ddns address. I think that should eliminate wi-fi from the equation.

 

[john9527]

@DTM - Did you ever have a firmware loaded on the AC88U that worked? Have you tried rolling back to 384 code?

 

[DTM]

No, I just acquired the 88U and have put the last two versions of Merlin on it. Both of those had the same behavior.

 

[DTM]

@DTM - Did you ever have a firmware loaded on the AC88U that worked? Have you tried rolling back to 384 code?

I just tried rolling back to the last 384 release. Same result. 10 fps on the 192 address and 5 fps on the ddns address.