Hey @jpm, what kind of fibre and optics do I want? going to do 2-4 ~10m runs.
I am currently getting in way over my head with a 25 gigabit Mikrotik switch but this started as point to point runs.
Think future-proof, not necessarily cheap but of course some of this shit is going to come #StraightOuttaShenzen
Looks like I might have painted myself into a bit of a corner with some "cheap" SFP28 gear, too, but I'm not too attached
@voltagex the second option is "multi-mode" fibre optic cables and optics. Traditionally, they were cheaper than "single-mode" but this is no longer true, because cheap VCSEL lasers are now capable of single-mode emission. They operate in the 850nm near-IR light band, and cables are generally constructed from 50um diameter plastic or glass cores. Because of the loose tolerance of the optics and fibre cores, their range is usually limited to 300M, and there's multiple grades of multi-mode fibre available with corresponding limitations on distance vs speed similar to copper ethernet cables. If you're buying new now, just go with OM4. OM1 cables use 62.5um diameter cores, and are only usually found in up to 1Gbit/sec applications. OM2 and later are all 50um diameter cores, but the optical transmission properties vary between generations which will limit transmission length.
You definitely don't need the fancy hybrid single-mode optics that use multi-mode cables unless you're trying to run 10GbE up the side of a building with ancient OM2 multi-mode cable plant.
@voltagex the third option is "single-mode" fibre optic cables and optics. This is where Shit Gets Real, and you do not look at energised optics with remaining good eye. Luckily, the actual cables are already so good and cheap that you just buy whatever from a reputable vendor and it'll work with any new single-mode optical devices you ever want to attach in future.
The optical devices on each end, however, are another matter entirely.
The basic consideration is the range class - typically either 10km, 20km, 40km, 80km, or 120km. Direct correlation to how much power the laser uses, and how expensive the modules is. Faster speeds may not get the 120km range class. Yes, you can have a single piece of glass 120km long to carry your signals.
And then comes the "oh wow holy shit my mind is blown" consideration of WAVELENGTH DIVISION MULTIPLEXING
@voltagex and finally the "wavelength division multiplexing" single-mode SFPs specify their wavelength, which is then optically combined into a single fibre core and transmitted to the other end, where the multiplexer uses wavelength-selective optics to split the signals back out into separate wavelengths on multiple fibres again.
Oh yeah, and there's 2 kinds of WDM, "coarse" and "fine", but they both work the same way, the only difference is how closely the wavelengths are packed together.
Almost certainly you don't need this, but you can just attach WDM MUXes to the single-mode fibres you already have whenever you want!
Bereitstellung skalierbarer Netzwerktechnologie-Lösungen für Rechenzentren, Unternehmen und Internetdienstanbieter. Entdecken Sie Hochgeschwindigkeits-Netzwerklösungen zum Aufbau einer zuverlässigen und skalierbaren Verbindungsinfrastruktur. Weltweite Lieferung, professioneller Support.
@jpm @voltagex important to note though that they work by spoofing the manufacturer codes that switches check for because vendor optic lock-in is where they make cash money. So you can’t just throw any old FS optic in a Cisco and expect it to work — you have to get one with the Cisco coding.
Oh yeah and the Linux drivers for intel 10G cards default to enforcing this “vendor supported SFP” shit unless you explicitly set a kernel parameter because open source capture by corporations lol
@jpm @voltagex oh hey Joel want to see my favourite things that render your last sentence hilariously inaccurate when it comes to weird edge cases in broadcast/AV industry?
@arichtman @jpm @voltagex SFP+ DACs here and very happy.
Edit: but this is probably the turning point where I decide to run 25gbs when I move my NAS et al out of the livingroom.
@arichtman No?
I will disagree with @jpm here - only because I've tried some different gear. The Aquantia AQC113 NICs are fine, haven't tried the new Realtek 10 gig NICs but they are also reasonably low power.
SFP+ DACs are fine, 10 gig copper SFP+ is fine* if you have enough space around them for cooling.
https://www.aliexpress.com/item/1005009139011834.html
https://www.omadanetworks.com/au/business-networking/omada-accessory-media-converter/mc420l/ - this one in particular is great and doesn't get hot. @jpm happy to send you one to check out.
@jpm @arichtman @voltagex and the same as CWDM mux
e.g. random example:
16 Channels CWDM Mux or Demux, 1310-1610nm, with Monitor and Expansion Port, 4.5dB Typical IL, LC/UPC, Single Fiber, FMU Plug-in Module, Product Specification:Channel - 16 Channels , Wavelength - 1310-1610nm, Special Port - Monitor, Expansion Port, Technology - TFF (Thin Film Filter), Insertion Loss - ≤5.0dB, 4.5dB Typical, Channel Spacing - 20nm
@jpm @arichtman @voltagex the perils of seeing the thread via a reply and not the main line, and not a tree view.
Also, "dense" rather that "fine", but yes.
The cool thing with these is that because they're a purely optical device, each wl can be a completely different L2. we used to do a bunch of Ethernet and FC over different colours between failover sites.
@ThermiteBeGiants @voltagex nope, 40GbE is quite literally 4 x 10GbE in a trenchcoat that all transmit/receive at the same time. Most QSFP switch ports can be configured either as 40G (all 4 transmit the same frame at once) or 4 x 10G (all 4 transmit different frames at the same time). If you use the 4 x 10G mode, you can use a quad-breakout cable to send the 4 independent 10G signals to different devices. Now, the cool thing about some QSFP* optics is that they use CWDM inside the module, so all 4 channels are optically muxed into a single single-mode fibre core!
There is, however, a 50GbE SFP56 which is indeed a single 50G channel.
Adam ♿
I love this, so I
s0 Is Not A Sysadmin
Justified Ancient of Moomin
Malcolm Herbert
"Musty Bits" McGee
noodle
Julien Goodwin
Daniel Carosone
kauer
Garth Kidd