Wired gigabit-copper vs wired gigabit-fiber in new ISP deployment

Continuing the discussion from How high is the risk for using laptops with closed source BIOS?:

10(ish) years ago, Netgear was my go-to recommendation. I don’t know of any netgear box produced in the last… 5 years… which supports OpenWRT easily (as in, download the right OpenWRT image and drag/drop it into the firmware update box on the router’s web interface). I believe there are a few Netgear boxes which you can get OpenWRT running on through more invasive means (including JTAG programming or similar).

With regard to dedicated router and separate modem: modern protocols (V-DSL, DOCSIS, and similar) are not well documented, and typically implemented in silicon (as they really require an ASIC to push the speeds they get over the physical lines they have). For the most part, attempts to get those ASICs working on OpenWRT or similar have been… temperamental at best. At the very least, they end up needing both a firmware blob and a blob kernel driver, which significantly degrades the trustworthiness of the system. If you are buying equipment up front (which you should do if you think you’ll want the service more than about 3 months), you can buy a dedicated just-a-modem, plus a TP-link or similar device, for about the same price as a slightly higher end all-in-one modem. Considering that the TP-link half goes with you across ISPs and is likely to continue to function for as long as the speeds it can manage are good enough for you, you’re money ahead this route the moment you switch services and get a new dedicated dumb modem.

to not derail the other thread any further i’ve decide to snag this over here regarding my particular dilemma as follows :

for some time my ISP has been taking the necessary steps in order to deploy wired gigabit ethernet connections as opposed to just the classic “gigabit ethernet” connection through copper that i’ve been running so far without a problem.

the way they’re introducing this is quite new to me since i’ve only seen it deployed at my neighbor next-door and i’ve no idea if i should bother changing or if i’m allowed TO change if i want to KEEP my www connections wired ONLY (i.e am not interested in getting a local 3g/4g modem-router gateway to my WAN yet)

i’m currently using a CAT 6 classic copper capable between my ISP’s few years old local gateway BOX that seems to NOT be UPS-ed (to my vexation) and my LAN switch (the one i mentioned earlier).

the way this change is set to occur is as follows. my CAT 6 copper cable is supposed to be replaced by a new optical-fiber cable capable of gigabit speed (the thin variety ones not the thick ones) between the WAN gateway and a newly deployed ISP issued modem/router that acts as a local gateway for my LAN (at least that’s how i’ve seen it work at my neighbor that was previously using a proprietary 3g/4g modem/router/gateway - same ISP but different contract)

since this is a new system. optical coax (new) vs ethernet-rj-45 (classic) where would i be able to get a proper firewall/router box that i can flash my own free-software firmware on ?
i ask this because i highly doubt that my ISP would be OK with me flashing their supplied equipment (although as i understand it the said equipment isn’t going to cost more as a RENTED service in addition to my speed service contract price - unlike other ISP contracts that DO charge EXTRA for the added modem/router).

could this mean that my ISP was thinking ahead about my well being, and foreseeing that i WANT to get an open-hardware device, was simply making it easier for ME to buy what i WANT ?

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Given that this is cutting edge, new “stuff”, I can’t speak to the limits of what you can do. With the classic *DSL technology, the DSL connection uses special hardware and closed implementations to talk from the box that plugs into your wall, through your wall, and to a device under the control of your ISP. This is the ethernet equivalent protocol. It does no routing, only direct communication. Once that channel is established, one of several open standard protocols are used to negotiate IP addresses, DHCP, or whatever else. Again, the “classic” protocol is some variation of PPP (mine is PPPoE). You can have a discrete device negotiate the PPP (or similar) layer, by telling the modem to act in “passthrough” mode. Passthrough mode makes it behave (from the perspective of the one device connected to it) almost exactly like the old telephone modems of yore.

If the modem refuses to act in passthrough mode, it will have to negotiate the IP-layer stuff on your behalf. This is fine, except that it makes the next step slightly more complicated. Your next-best option is to “DMZ host” your real router. This tells the modem/dumb-router to pass all incoming connections (and UDP datagrams which are not reply datagrams) to a particular internal device. If you can’t explicitly DMZ host your router, you may still be able to set a static port forward for 0-65535 to its external IP address. In the worst case, you end up with your internal router NATting your real network, and having to fight with the extra layer of firewall. Not the end of the world, but a bit tedious. On a side note, if your ISP offers IPv6, and follows the IPv6 specification, you get a fairly large block of IPv6 addresses allocated to you, at which point the NAT issues largely go away. Then again, I’ve yet to find a residential ISP that actually follows the IPv6 spec.

Anyway, that’s the situation as it has been W.R.T. using OpenWRT or similar behind a dedicated modem. With the new technology you’re facing, it is less likely that you’ll be able to do the passthrough route, but port forwarding or DMZ hosting (or NATting) should still work. If it turns out that they are using a standard protocol for IP-layer negotiations, you may still be able to use passthrough mode.

indeed mine as well.

the thing is that this “optical” cable is a few times thinner in diameter than a “classic” copper wire (my CAT 6 is a little thicker than my previous CAT 5) and the ISP gateway MAIN distribution box is WAY smaller than the box CURRENTLY in place that all the copper wires go into.

there is no doubt in my mind that the new system is all very modern and cleaner looking on the outside (the stairwell) not to mention less space taken overall. it probably ALSO consumes way less power since it’s optical based and not copper.

what you are referring to the DMZ in this case is what (in my case) ? the newer ISP supplied modem/router that acts as a “bridge” between my LAN and my ISP’s WAN or my wannabe firewall/router/modem box that i don’t even know it exists yet that can replace the one offered by my ISP (the only one i’ve seen so far with an optical jack) ?

so far i’ve only seen open-hardware products that feature an RJ-45 port but not a single one with an optical port from the WAN side …

bottom line is that with this NEWER system (even if i WANT to plug the optical cable straight into my LMini NIC) i will be UNABLE to do so since the LMini has only one RJ-45 port from the integrated NIC so that i’m FORCED to have a “box” between my thin-client and the primary ISP controlled WAN gateway box instead of how i’ve been doing it so far (plug the copper cable directly into my NIC without anything in between my LAN and WAN)

for my ISP the solution would be simple :slight_smile: “just use our supplied HW and connect to it’s WiFi access point then just set up your LAN-bubble from there”.

well, what if i’m allergic to WiFi and want to keep it as far away from me as possible :stuck_out_tongue: ?

i’ve edited the title from gigabit-ethernet to gigabit-copper to better reflect what this thread is about …

the thing is that these guys have been pushing this system for a while in larger cities and the CAPITAL whereas this has only reached ME now because i live in a very small town with less www demand but the process has been accelerated in recent years with more aggressive pricing and that’s probably why they don’t bother encrypting the connection between the server to the client … illustrated bellow


or maybe it is encrypted between the WAN and the WWW and it’s just my connection to the gateway that is left in plain text :slight_smile:

i’m just making wild assumptions here since i have NO idea how that BIG BOX outside works only that when there is a black-out my www dies but NOT my PC :sweat_smile:

Using encryption with PPP in this scenario is relatively, er, pointless. It would only be encrypted between the two endpoints. One endpoint is Customer Premises Equipment (CPE) - some box at your place - and the other endpoint is some box in your ISP’s network. So in no way shape or form is the encryption end-to-end, and you would end up wanting to layer E2EE over it anyway.

That said, it depends on what your threat model is and it depends on exactly where the CPE is.

Adding: MPPE is comparitively broken (weak) anyway.

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Ah but with any circuit, there WILL be choke points. All you need is a grand unified theory of wiring and a T-shirt.

I’m not too sure what the optical cable is for. Is this a fibre cable coming from the street. Like my place, photo of my NTD (network termination device). Here I just have a CAT6 to the WAN port on my router, which can be any router I want. The CAT6 can handle 1 Gbps. Or is it VDSL2.xx coming on a single pair copper cable? Depending on the DSLAM (digital subscriber line access multiplexer) location it can also handle gigabit speeds.
Or are you wanting faster than a gigabit?


i don’t want faster than 1 gigabit/s speed in either fiber or copper. my workstation has 10gbps NIC on-board but i don’t use that for connecting to www (only for LAN sometimes and most times it’s unused). some people want/need faster than 1gigabit/s speeds but for my purposes i don’t NEED that. plus it would add to the cost while i can’t even max my existing 1 gigabit/s connection which is a bummer but i can live with that so far …

being directly connected through optical would (probably) reduce latency times significantly for gaming since that’s probably what determined my neighbor to switch in the first place :sweat_smile:. i can’t complain on my existing copper CAT6 but the less latency (in this case :stuck_out_tongue_winking_eye: ) the merrier. but there are plenty of freedom restrictions in this case (if switch to optical) as i have already mentioned.

to be clear, this isn’t the first time i’ve seen an optical fiber cable used by the ISP but it IS the FIRST time i’ve seen one so thin deployed so near my endpoint (practically one node away from my PC-desktop-terminal). so far (as i’ve already stated) they have been using copper CAT5/6 for gigabit connections near client end-points.

but i get why me talking about this might seem strange as most people get their apartment/house already set-up AND wired according to spec so they probably don’t even see or are aware of this stuff (behind the scenes) except for the LAN router that’s probably somewhere nearby in the home/room.

@dean i can’t really make out much from that picture. is that an end-point router provider by your ISP ?

The image is a modem owned and operated by the network owner (NBN Australia). There is no interface for me to access it. The small white cable coming down the wall is the internal fibre cable from the street, the blue coil is the exposed fibre cable. There is an external box that connects the external fibre cable to internal fibre cable, buts that is a passive connector.

I have a CAT6 cable coming from the modem to my router. My router has an inbuilt wifi access point, 4-port switch, and DSL modern (which I don’t use), and a WAN port that connects to the networks modern. The router’s WAN uses Ethernet. Some ISPs wants you to use their router, but my ISP doesn’t care.

The speed of light through a fibre is the same as electricity through a copper cable, so no latency difference. You have a local network (LAN) and a wide area network (WAN). The router is a ‘device’ that links the two networks together. You want full control of your local network and router. The modem/WAN should be ‘controlled’ by the ISP. It’s the meter box.

I think I know what you’re talking about now. It’ll be a router with an SFP+ fibre connector?
I don’t think this will bring a lot of benefits. The bottle next is always the www/WAN/internet (same thing) and it’s rare to move around large GB files around the local network.

I think it’s just another way for the ISP to make more money by renting out a fancy router.

Edit: I think gateway and modem are the same things. I just haven’t heard the term gateway since the early 2000s. Unless you are getting 1Gbps internet service don’t bother with the fibre. Is the large optical cable you’re referring to is TOSLINK?

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The primary advantage of optical fiber over copper is it is non-conductive. No ground-loops, no EMI-induced noise, no risk of a lightning strike hitting a different building (or power pole) and sending a pulse over the cable and frying your expensive electronics.

That said, there is a latency difference (and speed difference) between copper and fiber; the signals in neither one travel at c (speed of light in a vacuum). How fast signals travel through optical fiber is pretty easy to calculate (will depend on the particular cable used, but not on the devices attached). Common silica-glass fiber optic cables often hit somewhere in the 0.66c range (multi-mode fiber is an additional 30ish percent slower). Copper cable’s latency depends on the drive power of the sending end, the gauge of the wire, and the length of the wire. While the leading edge of the electromagnetic wave will reach the receiver at nearly the speed of light, the “message” doesn’t arrive until the potential at the receiver’s end is over a specified value (usually about 50% of the maximum signal voltage). Anyway, on most copper runs, the media-latency is actually lower than fiber (I’m ignoring the latest fiber which hits 0.997c, as it’s not actually available commercially yet). The issue is that, while fiber is a truly digital media (letting you send multiple signals down it before the first one has arrived), copper is an analogue medium, on which we assign digital significance (so you have to wait for the other end to read the current bit before you can send the next). Also, the encoding and decoding of the signal takes time (in both cases), but the fiber signal is much simpler to decode (in large part due to the lack of EMI).

As for gateway, there is a technical difference between a gateway and a modem. A gateway is a device which engages in protocol translation. This means if you want to talk via IPv4 to an IPv6 website, you go through a gateway (which is likely not also a modem). A modem (literally a modulator/demodulator) does physical translation, typically between an analogue medium (like a telephone wire) and a digital medium (like “ethernet” (itself a misnomer in this context)). The terms have been muddied quite a lot, as modem is still used when talking about the gateway between your router and the modern digital telephone line.


Like the one I got hooked up to my land line to autoanswer on the first ring the robocalls. Had to put a loopback connector on the RS-232 port so it thinks its connected to something otherwise it won’t answer.

i get that for only a couple linear meters of cable the impact the difference in having a copper vs fiber pipe is negligible or almost non-existent considering the vast distances packets travel through the www infrastructure (made of high-grade FIBER-OPTICS especially the ones under the ocean) but depending on how complex you set-up your LAN to be then fiber-might have some benefits.

oh and by-the-way this thin fiber line was pretty forgiving regarding twists and turns unlike what i’ve heard about the thicker (main) FIBER lines between LAN and WAN and intra-WAN and between WAN and WWW.

in this context www is just a really big collection of WANs. kind of like galaxies are in the observable universe and LANs are just planets :wink: