Need just one more network port than you’ve currently got available (often: none)? A splitter can do the trick; just spend a few extra bucks to make sure you’ve made the right pick.
I’ll begin this teardown with an analogy. Imagine you’re grilling weekend hamburgers for the family. After the patties are cooked (medium-rare, of course), you slot them in buns and load them up with per-recipient preferred extras—lettuce, pickles, tomatoes, onions, mustard, and the like. The one condiment everyone wants is catsup (of course, again). But then you belatedly realize that there’s not enough of the tomato-derived sauce left in the bottle for everyone; specifically, one of the kids is about to be catsup-deprived.
Obviously, this just won’t do. But if you run to the store for more, the food will be cold by the time you get back. Plus, everyone’s already starving. And none of the neighbors, specifically those that you know well enough to even think of knocking on their doors and asking to borrow some of their catsup, are home. But then you remember the spare catsup packets from a recent take-out meal, jammed in the back of the refrigerator. An imminent condiment crisis is averted!
Or take this one. Your four-cylinder car is already paid off, in solid cosmetic condition and (mostly) equally great functional shape. But it just doesn’t have the “get up and go” that you’re now looking for. You could finance a more powerful replacement. But assuming you could even find someone to sell your existing vehicle to, or a dealer willing to take it in trade, you won’t get what you think it’s worth. And did I already mention that the one you already have is debt-free?
But then you realize you’ve only been putting regular (vs premium-octane) gas in it all this time. And/or that it’s been a while since you’ve taken it to the shop for a spark plug swap and broader tune-up. And/or maybe just that its tires are underinflated, or your trunk is overfilled. Rectifying these shortcomings transforms your existing vehicle, making it sufficiently spunky such that you can shelve the alternative of a replacement, keeping money in your pocket in the process.
An RJ45 in every port
What’s this all got to do with technology, specifically with Ethernet splitters? Well, multi-port Ethernet switches commonly come in the following configurations:
- 5-port
- 8-port
- 16-port
- 24-port
- 48-port
(10- and 12- port models, and other variants, also exist but are less common and therefore tend to be much more expensive on a per-port basis).
What happens if, as I’ve repeatedly experienced over the years, I have an eight-port switch already in service and fully populated, but then add another wired Ethernet device to my LAN (for example, another NAS)? This leaves me needing one more port, but I don’t have any available spares. I could:
- Replace the 8-port switch with a 16-port successor: an expensive transition proposition that also leaves me with a perfectly good but now-unused 8-port switch predecessor, or
- Add a separate 5-port switch to the mix, connected to the original 8-port switch using a short span of Ethernet cable. While this is more economical than the prior approach, it “wastes” a port on both switches, dedicated solely to the interconnect between them, plus it takes up more space on the networking equipment shelf (along with another power strip spot).
Passive deficiencies
But there’s a third option, which I’ll be analyzing today. It’s a splitter, most commonly found in 1:2 ratio variants such as today’s dissection victim, although larger configurations are also available at least in active, versus passive, splitter form. What’s the difference? Passive splitters, as their name suggests, are unpowered (I’m also assuming here that they’re not self-powered, specifically via PoE). They’re also quite inexpensive, as this $8.99-total pair of them exemplifies:
Alas, they’re not a perfect panacea. Not even close. In this particular implementation case, notice the “(Can’t Run Both at The Same TIME)” qualifier right in the product title, conceptually replicated in another stock image, although the embedded verbiage muddies the waters as least as I’m interpreting it:
What’s basically going on with this particular implementation of the concept (with thanks to a knowledgeable Amazon reviewer, whose graphics I’m “borrowing”) is that the eight Ethernet wires flowing into one end of the splitter are duplicated at both connectors on the other end:
The upside? From a performance standpoint, both split-end (see what I did there?) connectors use all eight original-end wires (hold that thought). The downside? If you plug active devices into both “split” connectors at the same time, neither of them will go online. Not to mention all the short-circuiting going on between all three devices mated to the splitter, which should instead be called a duplicator (or maybe an overly complicated and potentially tragic coupler).
In the other implementation of the concept, which as my Amazon reviewer friend points out, often looks identical from the outside, four of the eight original-end connector wires go to one split-end connector, with the other four going to the other.
There are upsides to this variant approach, potentially. No short circuits, for one thing. And depending on how the wiring is handled at the other end of the cable plugged into the splitter’s original-end connector, gear plugged into both split-end connectors may be able to coexist. But since each of them is only using four wires of the total eight-wire strand, they’re each restricted to 100 Mbps peak bandwidth, since GbE connectivity requires the use of all four two-wire sets.
Active rationalization
Powered (active) splitters are the real deal. Essentially, they’re mini-switches, with a subset of the total number of connectors found in a “true” five-port (or larger) switch. Take today’s Goalake 2:1 patient, for example, which set me back only $6.49 post-35%-off-promotion when I bought it from Amazon in December 2024.
Along with its 3:1 sibling, which I’d purchased at the same time for only $9.09.
No inter-device packet collision issues, plus full GbE bandwidth to both “split end” devices, albeit subdivided between them if they’re concurrently transmitting or receiving.
With the stock image out of the way, let’s now look at the “real thing”, starting with box shots accompanied by a 0.75″ (19.1 mm) diameter U.S. penny for size comparison purposes, as usual.
Packaging contents
Open ‘er up, and inside you’ll find a slip of paper up top:
with the rest of the goodies below:
Extras first, also including a USB-A to USB-C cable, whose purpose you’ll see shortly:
And now for our patient, initially translucent-swathed:
And now “unclothed”:
This side you’ve already seen in the “stock” image:
These two are, like the bottom, bland:
And this one explains why the aforementioned included USB cable exists:
It’s for the USB-C incoming power connection:
To my earlier “takes up more space on the networking equipment shelf (along with another power strip spot)” crack, this device in contrast is pretty tiny (58.1 mm x 23.4 mm x 62.8 mm). And although you could plug the USB-A end into a dedicated “wall wart”, the power requirements (5V@1A) are low enough that you could instead leverage an already-available and otherwise-unused USB connector coming out the back of a nearby NAS or UPS, for example.
Unsurprising (and highly integrated) innards
Time to get inside. You probably already noticed the four screws, two on each end. And you probably already guessed what comes next:
Turns out, I didn’t necessarily need to remove both ends’ plates; I could slide the PCB out either:
Oh well…nothing wrong with being thorough:
Note the lingering glue on the inside-chassis slot, to hold the PCB in place as originally installed:
Speaking of which, not much of note on this PCB side, save for more glue remnants and the fact that the manufacturer went with multiple smaller LAN transformers per-connector versus one unified per-connector alternative, as I’ve seen in other wired Ethernet-inclusive products.
The other side’s more interesting, albeit only a bit, reflective of the minimized bill-of-materials cost for this low-priced device.
That thermal pad presses up against the lower half of the (aluminum, I presume) chassis when the PCB is in place. Let’s see what’s underneath:
Surprise, surprise (not)…an Econet (later merged with Airoha Technology, both subsidiaries of MediaTek) EN8850DHE five-port switch with embedded 10/100/1000Base-T PHY!
That’s all I’ve got for you today. Reader thoughts are as-always welcome in the comments!
—Brian Dipert is the associate editor, as well as a contributing editor, at EDN.
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