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Fzang

macrumors 65816
Original poster
Jun 15, 2013
1,315
1,081
I live in a dorm where using the internet requires one to log in. I have set up an Airport Express in my room and set it to DHCP/NAT which enables me to log in one and then use wifi freely on all my devices. However, this gives insanely slow wifi speeds.

If I connect directly with bridge mode I get lightning fast internet, but then I can only use one device at a time, and I have to go through a lot of logging in/out troubles to use a different device.

I have tried every possible configuration I could think of... Can anyone give me some pointers?
 

Altemose

macrumors G3
Mar 26, 2013
9,189
488
Elkton, Maryland
The router doesn't say anything about double NAT issues though. Not a problem then, is it?

When you have two routers in a single chain you have a double NAT issue. The speed issue is likely occurring as the upstream router is throttling your port. Another possibility is that running a double NAT firewall is causing the problem. Older AirPorts would let you use DHCP to distribute addresses without using the NAT function. I doubt that is still an option.
 

Fzang

macrumors 65816
Original poster
Jun 15, 2013
1,315
1,081
When you have two routers in a single chain you have a double NAT issue. The speed issue is likely occurring as the upstream router is throttling your port. Another possibility is that running a double NAT firewall is causing the problem. Older AirPorts would let you use DHCP to distribute addresses without using the NAT function. I doubt that is still an option.

It does have a DHCP-only mode. However, I was under the impression that NAT is absolutely required for one-IP-per-login systems commonly used in dorms and public hotspots?
 

Altemose

macrumors G3
Mar 26, 2013
9,189
488
Elkton, Maryland
It does have a DHCP-only mode. However, I was under the impression that NAT is absolutely required for one-IP-per-login systems commonly used in dorms and public hotspots?

Not necessarily. DHCP would give one IP to the AirPort and create a separate DHCP range for clients connected to it. The DHCP option is under the "Network" tab correct?
 

Fzang

macrumors 65816
Original poster
Jun 15, 2013
1,315
1,081
Not necessarily. DHCP would give one IP to the AirPort and create a separate DHCP range for clients connected to it. The DHCP option is under the "Network" tab correct?

Correct.

If I set router mode to DHCP-only and try to update, I get

"Sharing a range of IP addresses using DHCP Only requires manually configuring your WAN IP address. If your ISP gives you a range of static IP addresses, you should manually configure your base station with the first IP address and distribute the rest via DHCP."

So I should connect via "static" instead of DHCP? Which IP addresses should I use? With DHCP my IPv4 is set to 210.77.14.38; should I put this in static instead?
 

Fzang

macrumors 65816
Original poster
Jun 15, 2013
1,315
1,081
Yes. Copy all of the information and input that in as static.

I've tried several combinations now, and I'm finding that

Static + bridge mode = good speed
DHCP + bridge mode = good speed
DHCP + NAT/DHCP = terrible speed
Static + DHCP = no connection
Static + NAT/DHCP = no connection

Maybe I'm doing this wrong? :confused:
 

Altemose

macrumors G3
Mar 26, 2013
9,189
488
Elkton, Maryland
I've tried several combinations now, and I'm finding that

Static + bridge mode = good speed
DHCP + bridge mode = good speed
DHCP + NAT/DHCP = terrible speed
Static + DHCP = no connection
Static + NAT/DHCP = no connection

Maybe I'm doing this wrong? :confused:

They are using an upstream router with a clear policy against routers as they "segment" the network. Your best option would be to manually log in on all devices or use the campus Wi-Fi if available.
 

Fzang

macrumors 65816
Original poster
Jun 15, 2013
1,315
1,081
They are using an upstream router with a clear policy against routers as they "segment" the network. Your best option would be to manually log in on all devices or use the campus Wi-Fi if available.

That's too bad. At least I found my problem :eek:

I can only connect with one device at a time (hence the reason I wanted to use NAT) or it'll ask for login and kick off the previous device. But I guess fast internet for one device is better than unusably slow internet for several devices :D
 

Altemose

macrumors G3
Mar 26, 2013
9,189
488
Elkton, Maryland
That's too bad. At least I found my problem :eek:



I can only connect with one device at a time (hence the reason I wanted to use NAT) or it'll ask for login and kick off the previous device. But I guess fast internet for one device is better than unusably slow internet for several devices :D


Unfortunately you are at the mercy of the network engineers and administrators at your school. Though, if they do not want wireless routers or APs they should have a strong ubiquitous network.
 

Fzang

macrumors 65816
Original poster
Jun 15, 2013
1,315
1,081
Unfortunately you are at the mercy of the network engineers and administrators at your school. Though, if they do not want wireless routers or APs they should have a strong ubiquitous network.

I study as a foreign student in China, and some things are just a bit slower here. Internet is one of them.
 
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