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Can the SFP of an Netgear prosafe GS724T used for an SFP VDSL2 modem?

#1

My VDSL2 modem recently decided to quit its job. Now I am looking for an replacement / upgrade. The privious device was a AVM Fritzbox 7390. I think it is nothing more than a plastic paper weight.
Currently, I am lurking around free hotspots which is not ideal.

I have a Netgear GS724T-400EUS. This is a 24port gigabit switch. It has 2 empty SFP slots. I am not that familiar with SFP, yet. On the internet I found a ALLNET ALL4781-VDSL2-SFP which seems to be a VDSL modem that supports all the current standards including G.993.5 which is essential for my connection to my ISP.

Is SFP meant as plug-and-play solution the way I intend it to use or does my netgear switch need to support that specific card.
If the SFP card is not possible, are there pure modems that you can recommend which support VDSL up to the profile of 35b?
I want to add in a pfsense rackmounted box later, but right now I need working internet connection first and foremost.

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#2

What ISP? what vdsl2 profile/speeds?

You might need some kind of router capable of pppoe until your pfsense is ready

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#3

My ISP is: Telekom (Germany)
My booked and delivered speed is: 100 Mbit/s (down), 40MBit/s (up)
The profile is: 17a

I thought about my initial post for a while and figured that it would be impossible for a Netgear switch to support any kind of WAN connectivity.
It is a switch and not a router, therefore it lacks some capabilities.
I bought an Ubiquiti edgerouter 4 and the SFP modem after long debate what to do best.

Now the one thing that I can’t figure out in my head. What exactly does my ISP actually deliver to my house? I have seen that the interfaces of the edgerouter can be set to PPPoE, but that does not automatically mean that I can plug it straight into the TAE socket from the wall, right?
If I am not mistaken:
The ports on the router do use IPv4/IPv6 over Ethernet.
The signal from my ISP is PPPoE via vDSL (layer 2)
I need a vDSL2 modem either in the router (which the edgerouter doesn’t have) or external as device between the wall and the edgerouter.

Networking is not new for me, but I am a bit rusty on the Link Layer.

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#4

SFPs are a standard form factor however they do rely on software support in the networking device’s OS. Think of them like PCIe expansion cards (they aren’t but you get the idea).

This can bite you on Cisco for example if you run an IOS that is too early to support a newer model SFP.

So given that, I’d suggest that you may also run into that issue mixing and matching SFP modules from different vendor(s) and devices.

I’d suggest trying it, but just don’t be surprised if the device isn’t detected.

If you had a VDSL2 modem then the protocol being delivered to your house would be VDSL2. Not ethernet, so yes - you won’t be able to plug your router directly into the wall socket without a modem to convert from VDSL2 protocol to ethernet.

Once the VDSL2 is bridged to ethernet by the modem, then it may or may not require use of PPPoE or similar.

My old VDSL2 based ISP here in Australia used to use PPPoE, my new one (still VDSL2 based) just looks like regular ethernet behind the VDSL modem and they allocate an IP address/subnet via DHCP/DHCPv6 and IPV6 prefix negotiation.

There’s more than one way to skin a cat on the “behind the modem” side, and different ISPs do different things.

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