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Comment by Bluecobra | Hacker News Reader

What sucks about this situation is when your ISP forces you to use their modem or router. For example, I have AT&T fiber and it does some kind of 802.1X authentication with certificates to connect to their network. If they didn't do this, I could just plug any arbitrary device into the ONT. There are/were workarounds to this but I don't want to go through all those hoops to get online. Instead, I ended up disabling everything on the AT&T router and have my own router that I keep up to date plugged into that. Unbeknownst to me, the AT&T router could be hacked and I would never notice unless it was adversely affects my service.

Thank god most things use HTTPS these days.

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If you have the att fiber with the ONT separate from the modem, it's really easy to bypass 802.1X. Plug an unmanaged switch in between the modem and the ONT; let the modem auth; disconnect the modem. You'll likely need to do that again if the ONT reboots, but at least for me, ATT a UPS for the ONT, so reboot frequency should be low.

Personally, I built up a rube goldberg of software and hardware with bypass nics so if my firewall was off (or rebooting), traffic would flow through their modem, and when it was on, my firewall would take the traffic and selectively forward traffic through from the modem, but there's really no need for that when you just use an unmanaged switch. I can find the code if you're interested (requires FreeBSD), but you sound more sensible than that ;)

That's a good idea, I do have an extra UPS/switch I can use for this. In the past when I was a bachelor and had more free time, I used to run my own FreeBSD server with pf and other services running in jails. Now that I am settled down, I just want to make things as idiot proof as possible in case there is an Internet issue at home and another family member needs to fix it.

The XGS-PON workaround that DannyBee looks promising though:

https://pon.wiki/guides/masquerade-as-the-att-inc-bgw320-500...

I probably could pay to upgrade my speed to 2Gbps and then downgrade it back to 1Gbps and keep the XGS-PON.

If you have a router running PfSense Plus* and at least 3 ports, Netgate actually has pretty detailed instructions for how to do the bypass with their layer 2 routing feature. It sounds a bit complicated, but I followed along exactly as it says and it just worked for me. Has been 100% reliable for almost 2 years, and I get significantly better speed (something like 10-20% vs the built in "passthrough" mode on the gateway, iirc). Plus I managed to cut the suspicious DNS server the gateway tries to interject out of my network.

> https://docs.netgate.com/pfsense/en/latest/recipes/authbridg...

There's another method that doesn't require Plus called pfatt, but I'm not sure what the state of it is.

* Plus is the paid version, yeah I know I agree I don't like what they did with the licensing changes but that's a different story

How does that bypass 802.1x? Are the 802.1x packets are responded to by the official modem still? I was under the impression all packets were encrypted or signed with 802.1x, but Ive never had to implement or test it so I could be wrong.

802.1x is a secure login procedure, and then the port is open until link is dropped. There's no encryption or authentication per packet (it would be way too expensive), and if you put a switch between the ont and the modem, when you disconnect the modem, the ont doesn't see the link drop.

Managed switches or software ethernet bridges don't always propigate 802.1x packets, but unmanaged switches don't care.

> There's no encryption or authentication per packet (it would be way too expensive) […]

It is possible to tie together 802.1X and MACsec, and plenty of (Ethernet) chipsets can do MACsec at wire speed, even up to 400G and 800G:

* https://www.arista.com/assets/data/pdf/Datasheets/7800R3_MAC...

* https://www.juniper.net/us/en/solutions/400g-and-800g.html

I don't know the telco space well enough to know if there's a MACsec-equivalent for GPON, but given the 'only' 25G speeds involved I doubt it would be much of a challenge.

The CPE AT&T router potentially getting hacked doesn't make much difference if you have your own router between your network and the AT&T network. Even if we removed the AT&T CPE router, you'd still be connecting to a black box you don't control that could be hacked or doing any number of inspections on your traffic.

It does matter since it lets an attacker be between your network and the internet. If that black box is a modem- yes it could be hacked, but (maybe luckily for me) the providers I've used don't expose many services from the modem on the public interface so it's much more difficult to compromise. You'd either have to come from the docsis network or the client network.

But remove the CPE router. Where do you think that fiber goes? To "the internet"? It's going to yet another box owned and managed by your ISP. And from there, probably yet another box owned and managed by your ISP. And then another black box maybe owned by yet another ISP, and then another black box owned by maybe yet another ISP. Each one of these could let an attacker come between your network and "the internet". You have no control over them. You don't patch them, you don't configure them, you have no say over the services running on them. If they're compromised, you likely wouldn't know.

The CPE just moves the first black box inside your home, but there's always some ISP black box you're connecting to. Even if you're a top tier network, it's not like you control every box between you and every other site you want to go to. You're going to eventually have some handoff at some peering location, and once again your traffic goes to a box you don't control just waiting for an attacker to manipulate and mess with your traffic.

The CPE also moves the first black box under foreign control to (potentially) both sides of your firewall, as most small businesses likely just use the router in that mode, and have very little networking knowledge. That's significantly worse than somewhere on the outside of your firewall because now it can snoop pretty much everything and be used to scan the local network which is often poorly protected because it's assumed to be pretty secure.

Hence my first comment:

> doesn't make much difference if you have your own router between your network and the AT&T network

And in the end those businesses with no networking knowledge will end up using their ISP's CPE modem/router/WiFi combo regardless of if its required or not. And from my experience it is not even just AT&T requiring their CPE router somewhere in the stack. I previously managed a Spectrum DOCSIS business internet connection where they also required their owned and managed gateway in the stack in order to have any static IP addresses. They wouldn't support any other configurations.

Fortunately, Cox isn't one of these. Any sufficiently modern DOCSIS modem, appropriate to the speed of service you subscribe to, is accepted.

Unfortunately, my praise of Cox ends there. I've been having intermittent packet loss issues for 2 years, and there doesn't appear to be a support escalation path available to me, so I can't reach anyone that will understand the data I've captured indicating certain nodes are (probably) oversubscribed.

Fwiw: the hoops are automated these days if you are on xgspon.

It's "plug in sfp+, upload firmware using web interface, enter equipment serial number"

You can even skip step 2 depending on the sfp stick you use.

The 802.1x state is not actually verified server side. The standard says modems should not pass traffic when 802.1x is required but not done. Most do anyway or can be changed to do so. AT&T side does not verify, and always passes traffic. That is what is happening under the covers.

It was mentioned by a sibling, but there are ways to connect without using one of AT&T's gateway devices. Different methods are catalogued on https://pon.wiki/

Like someone else mentioned, at some level you need to rely on your ISP and it is also a good idea to have a router in between anyway.

I would like to bypass the BGW320 because not only it is a large, power hungry box, but it also requires me to jump through hoops to get IPV6 working with VLANs. I need to either use multiple physical links (simulating multiple devices) or simulate that using a VRRP hack, otherwise AT&T will not give out multiple ranges at all (and will not care about what I request). Under Comcast I didn't have to do any of that, I'd just carve out smaller IPV6 ranges, as many as needed.

Always put your own router in-between.

If you really care you can configure a VPN directly on the router, so nothing leaves the network unencrypted.

That's why I'm not an AT&T customer. Spectrum lets me bring my own hardware, and they're the only other option in my area, so Spectrum gets my business. Plain and simple. Unfortunately, not everyone has the palatable solution that I have.

Spectrum remote manages your hardware even if you bring your own modem. This nearly entirely consists of deploying firmware updates once a decade, but they can also command other things like modem reboots.

If it's your own hardware, what's stopping you from closing the port they connect to?

DOCSIS?

How do you propose blocking a port between the cable network and your modem? You'd have to build your own custom firmware that doesn't acknowledge upstream firmware update requests.

AFAIK, they can/will kick you off the network if your modem is running unverified firmware. I think this is a regulatory requirement, but don't take my word for it. They don't want anyone to have free access to the network, you could do things like spoof your MAC address to get free service. I'm sure you could also do something much more malicious like crash parts of the network.

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