US Telco Support > AT&T > AT&T Midwest > Dynamic DNS with ATT MyFi hotspot . .

Dynamic DNS with ATT MyFi hotspot . .

Re WHOIS . . The reported public address may be an ATT proxy server, not my HotSpot. For Dynamic DNS to work, the public address has to be on the hotspot. If I already owned the HotSpot I could log into its management interface and check the "Status Page" but I haven't bought the unit yet because of this question. If the IP on the Status Page matches the WHOIS ip, then I would be good to go.

Re: IPCONFIG, That gives me the local private address of my computer assigned by the NAT router in the hotspot . . definitily not a public IP.

I need to know if the external address assigned to the hotspot is actually a public address, not a private address within the ATT network.

I guess I'll try a traceroute on my PC when it is tethered to my ATT iPad. The iPad might be on the same type of data network as the hotspot.

I have no hands on experience with a myfi hotspot

reply to swbca
The answer: It DEPENDS.

Hotspot: Public IP tunnel to the APN/gateway where the traffic exits.

Browser on phone (e.g. Android): Private IP behind AT&T Mobility's SGSN/GGSN or whatever they have now with direct IP tunnel and IP-RAN.

AT&T doesn't proxy/compress anything on mobile broadband ever since the 2000's with the EDGE/UMTS(HSPA+)/LTE network upgrades.

Why do you need dynamic dns? I don't get the technical point of it...

AT&T doesn't CARE what you run over it as long as you stay under the GB limit (5GB for example).

They have the right to QoS the data though so VoIP over the public internet may occasionally drop because UMTS voice has priority on the radio carriers (unless you are in a LTE market).

Same with every other carrier...

1. Are you sure you can't get wired/cable or microwave back-hauled local wireless!?

Why Dnyamic DNS
This is an unoccupied vacation home. Dynamic DNS lets us reach a Web interface running on a PC at this cabin that manages the lighting, temperature and security. When a HotSpot IP address changes, we would still be able to reach the Colorado cabin from Minnesota using an address like "cabin.domain.net:35000/log-in". We have doing this with an always-on Earthlink Dial-Up initiated from the cabin for 11 years.

It isn't a matter of what ATT allows on the network. It is a question of the HotSpot being on an inbound routable address (no ATT nat or proxy).

I tested our ATT (Cingular) Data Connection from an iPad that has ATT service. The ATT address assigned to the iPad was the true source public address that was logged on a destination web server. If the HotSpot is on the same type of network. . . dynamic DNS registration will work.

Alternative Service
This cabin is in an isolated place where no further developement is permitted, with no cable and poor phone line. We tried Satellite for a while but latency causes problems with with automated ftp photo uploads and with remote desktop access to the computer at the site.

Latency on ATT Data ???
Do you know the round-trip latency on ATT Data Network. I assummed it was better than Satellite which is now about 1 full second.

All mobile broadband is less than 200ms in 99% of cases now and less than 150ms in the majority of areas upgraded to 3G and less than 100ms in 4G areas RTT.

The cell site is back-hauled on fiber (if available) or jumps in industrial grade microwave (wireless fiber, carrier stuff) hops until it hits the fiber and is aggregated to the backbone.

You will get 10X better performance on mobile broadband than on satellite. ANYTHING is better than satellite.

With mobile broadband you are only going wireless for 3-5 to 20 miles at max in a rural area before it hits fiber/microwave. Satellite takes >20,000 miles, etc. to the earths atmosphere.

LTE is ~60ms RTT since its on 100% fiber back-haul or microwave+fiber.

Yes what you want will work. Just sign up for a connected device (computer, tablet, etc.) and you will always get a public IP.

AT&T only NAT's traffic on the smart-phones and things like that if I remember.

But be sure to *TEST* it first because they may implement a firewall policy (security)...

When I mean firewall I mean the device in Mobility's data-center that terminates your IP tunnel session and onto the internet. It is possible they can apply in-gress/egress filtering there for security reasons.

What is a connected device . . is that an alternative QOS to a normal device ?

Re NAT on mobile broadband . . . What I have found in last 24 hours.

ATT is all NAT on phones and hotspots . . no inbound routing.
Verizon gives public IP's with 3G connections and NAT on 4G. They said everthing will be NAT soon.

I Jailbroke ATT and Verizon iPads yesterday to get the local address. Then I called both carriers to find the NAT stories on hotspots now and in the future.