Hello,
- at what OSI layer this device work? at L1 like hub, or at L2 like switch?
- what delay does this device add?
- why distance is limited to 1500 m?
Does that really matter for a two-port device?
That’s because of the power drop. Check the official brochure for the details. You can build a link up to 3000m long if you provide power from both ends of the link (you will also need to adjust jumpers on GPeR devices in the center of the link).
- Of course it matters (and two port has nothing to do with it)
- ???
- Ok
Really … what’s the big difference between 2-port ethernet hub and 2-port ethernet switch?
And yes, port count has everything to do with it.
Instead of forwarding frame to the other port because forwarding table (MAC address list) of the second port contains the destination MAC (or sending it to all one port other than ingress if dst-MAC address is not there) … the hub just forwards the fscking frame to the other port. Without adding a microsecond delay needed to consult forwarding table.
The only case I can think of where the MAC table would be handy is if there was some switching problem elsewhere (so that GPeR would receife frame through one port and its own forwarding table said dst-MAC was accessible through ingress port … so that switch would reject to forward such a frame. But then, is this duty of a range extender?
Look at it as a media converter. It only put out what came in and the other way and amplify the voltage to make the next leg of the cable.
Is a delay a big criteria? Before then it even never arrived.
The GPER is a passive device that connects wires together, you can call it Layer1. This is not really a hub.
Regarding second question, GPeR doesn’t add any noticeable delay, for example, at 1500m you have 0ms ping response time and you still can push 1Gbps.
If GPER is just a passive device that connects wires together, then the price is perplexing (50% of Raspberry Pi 4 computer)
Can you name any other alternatives that allows to extend ethernet cable, without sacrificing PoE?
I can see a communication noise happening around here. How about MT guys writing a few lines of technical description about GPeR … what is it, how it works. Doesn’t really have to disclose some patented technology … I guess it’s about a fairly simple (electrical) signal shaper with some DC bypass (to allow PoE to pass), but still far more complex than a RJ45 coupler …
It’s an active device, product page mentions it already = Gigabit Passive Ethernet Repeater. repeater = 2-ports switch => datagram receiver and re-transmit.
I don’t see how this would introduce noise.
Yes, there is a basic switch chip inside.
normis
Tue Jul 30, 2019 9:57 am
The GPER is a passive device that connects wires together, you can call it Layer1. This is not really a hub.
normis
Fri Aug 02, 2019 3:14 pm
Yes, there is a basic switch chip inside.
Two completely different answers.
You are Dr Jekyll and Mr Hyde??
Well, take it this way. Mikrotik is marketing this as “passive” since they are trying to compete with various passive optical solutions here. The whole GPEN product line is just about that. But technically, none of the products in this line are really passive, IMO.
Sorry about confusion. I meant to say that it’s not a smart device, no software. Also, yes, “passive” is a bit confusing, as it does need the PoE power in to function. There is no delay though.
Why you’re lying to us?
There is Marvell 88E6341 (6port) switch inside so it’s not repeater, it’s 2-port switch. And it’s using store&forward so it add some delay (like any other switch).
going back to the basics of networks:
what is a hub? is a multiport repeater, because that it can only work in half duplex, for obvious reasons
its a fact you can’t do repeating in a full duplex gigabit ethernet segment, you have to do switching
i think its obvious gper is a switch because of the extended reach only achievable electrically regenerating the signal
this topic has become a very Byzantine discussion
a lot of questioning and criticisms for a 15 USD device you have not tried
i have tried it and works well, its a very useful and innovative device, its a matter of time to see it allow diverse and innovative solutions and designs
with the new GPeR IP67 Case, the possibilities are endless !!!
i think Mikrotik do a Good job whit this kind of disruptive devices, maybe too disruptive to be properly understood by some people
Who is lying to whom?
Passive means it is without configuration interface, just plug in and use it. There is no GUI to control it, it just works.
- L2 although think of it more like L1.
- None
- Voltage droop
It’s actually incredible that the device is on the market. The closest I have seen to this is a Veracity Outreach extender which is often more than 10 times the price.
I think the misunderstanding is because “Passive” is referred usually to a device that DOESN’T require power to be supplied…