Pictures of the internals of the Starlink adapter

Restoring Starlink’s Missing Ethernet Ports

February 28, 2024 by 29 Comments

Internet connectivity in remote areas can be a challenge, but recently SpaceX’s Starlink has emerged as a viable solution for many spots on the globe — including the Ukrainian frontlines. Unfortunately, in 2021 Starlink released a new version of their hardware, cost-optimized to the point of losing some nice features such as the built-in Ethernet RJ45 (8P8C) port, and their proposed workaround has some fundamental problems to it. [Oleg Kutkov], known for fixing Starlink terminals in wartime conditions, has released three posts on investigating those problems and, in the end, bringing the RJ45 ports back.

Starlink now uses an SPX connector with a proprietary pinout that carries two Ethernet connections at once: one to the Dishy uplink, and another one for LAN, with only the Dishy uplink being used by default. If you want LAN Ethernet connectivity, they’d like you to buy an adapter that plugs in the middle of the Dishy-router connection. Not only is the adapter requirement a bother, especially in a country where shipping is impeded, the SPX connector is also seriously fragile and prone to a few disastrous failure modes, from moisture sensitivity to straight up bad factory soldering.

Continue reading “Restoring Starlink’s Missing Ethernet Ports” →

Ethernet For Hackers: Equipment Exploration

February 28, 2024 by 28 Comments

Last time, we talked about the surface-level details of Ethernet. They are fundamental to know for Ethernet hacking, but they’re also easy to pick up from bits and pieces online, or just from wiring up a few computers in your home network. Now, there’s also a bunch of equipment and standards that you will want to use with Ethernet – easy to find whether used or new, and typically as easy to work with. Let’s give you a few beacons!

Routers And Switches

Whenever you see a box with a few Ethernet ports, it’s either referred to as a router, or a switch, sometimes people will even use the word “hub”! Fortunately, it’s simpler than it may seem. A router is a smart device, typically with an OS, that ties two or more networks together – routing packers from one network to another, and typically taking care of things like handing out local IP addresses via DHCP. A switch merely helps Ethernet devices exchange packets between each other on the same level – it’s typically nowhere near as smart as a router gets. Oftentimes, a home router will contain a switch inside, so that you can plug in multiple of your home devices at once. That’s the main difference – a switch merely transmits packets between Ethernet-connected devices, while a router is a small computer taking care of packet forwarding between networks and possibly including an Ethernet switch on the side.
Continue reading “Ethernet For Hackers: Equipment Exploration” →

Underwater Sensor Takes Single Pair Ethernet For A Dip

February 27, 2024 by 27 Comments

The 10BASE-T1 Ethernet standard is also known as ‘single pair Ethernet’ (SPE), as it’s most defining feature is the ability to work over a single pair of conductors. Being fairly new, it offers a lot of advantages where replacing existing wiring is difficult, or where the weight of the additional conductors is a concern, such as with the underwater sensor node project that [Michael Orenstein] and [Scott] dreamed up and implemented as part of a design challenge. With just a single twisted pair, this sensor node got access to a full-duplex 10 Mbit connection as well as up to 50 watts of power.

The SPE standards (100BASE-T1, 1000BASE-T1 and NGBASE-T1) 10BASE-T1 can do at least 15 meters (10BASE-T1S), but the 10BASE-T1L variant is rated for at least 1 kilometer. This makes it ideal for a sensor that’s placed well below the water’s surface, while requiring just the single twisted pair cable when adding Power over Data Lines (PoDL). Whereas Power-over-Ethernet (PoE) uses its own dedicated pairs, PoDL piggybacks on the same wires as the data, requiring it to be coupled and decoupled at each end.

Continue reading “Underwater Sensor Takes Single Pair Ethernet For A Dip” →

Ethernet For Hackers: The Very Basics

February 12, 2024 by 93 Comments

Ethernet is ubiquitous, fast, and simple. You only need two diffpairs (four wires) to establish a 100Mbit link, the hardware is everywhere, you can do Ethernet over long distances easily, and tons of the microcontrollers and SoCs support it, too. Overall, it’s a technology you will be glad to know about, and there’s hundreds of scenarios where you could use it.

If you need to establish a high-bandwidth connection between two Linux boards in your project, or maybe a Linux board and a powerful MCU, maybe make a network between microcontrollers, Ethernet’s your friend. It also scales wonderfully – there’s so much tech around Ethernet, that finding cables, connectors or ICs tends to be dead easy. Plus, the world of Ethernet is huge beyond belief. Ethernet as most of us know it is actually just the consumer-facing versions of Ethernet, and there’s a quite a few fascinating industrial and automotive Ethernet standards that flip many of our Ethernet assumptions upside down.

Now, you might be missing out on some benefits of Ethernet, or perhaps misunderstanding how Ethernet works at all. What does it mean when a microcontroller datasheet says “has Ethernet interface”? If you see five pins on an SBC and the manufacturer refers to them as “Ethernet”, what do you even do with them? Why does the Raspberry Pi 4 SoC support Ethernet but still requires an extra chip, and what even is GMII? Continue reading “Ethernet For Hackers: The Very Basics” →

All About Cats, And What Ethernet Classifications Mean Beyond ‘Bigger Number Better’

November 7, 2023 by 48 Comments

Although it probably feels like forever to many of us since Category 5 Ethernet cabling became prevalent, now that 2.5 and even 5 Gbit Ethernet has trickled into the mainstream, a pertinent question that many probably end up asking, is when you should replace Cat-5e wiring with Cat-6, or even Cat-7. Since most of us are likely to use copper network wiring for the foreseeable future in our domiciles and offices, it is a good question that deserves a good answer. Although swapping a Cat-5e patch cable with a Cat-7 one between a network port and computer is easy enough, replacing all the network cable already pulled through the conduits of a ‘future-proofed’ home is not.

The good news is probably that Category 8 Class II (Cat-8.2) is all you need to run your 40 Gbit Ethernet network with standard twisted pair wiring. The bad news is that you’re limited to runs of only thirty meters before signal degradation begins to kick in. If you take things down a notch to Cat-6A or Cat-7 (ISO/IEC 11801 Class EA and F, respectively), you can do 100 meter runs at 10 Gbit/s just like 100 meters runs at 1 Gbit/s were possible with Cat-5e before. Yet what differentiates these categories exactly?

Continue reading “All About Cats, And What Ethernet Classifications Mean Beyond ‘Bigger Number Better’” →

Adding Power Over Ethernet Support To A Mac Mini

August 14, 2023 by 10 Comments
Wiring up a Mac Mini's new PoE module. (Credit: Ivan Kuleshov)
Wiring up a Mac Mini’s new PoE module. (Credit: Ivan Kuleshov)

Despite all the fancy features on modern Apple Mac systems like USB-C and Thunderbolt, they have one glaring omission: the absolute lack of any form of Power-over-Ethernet (PoE). This is an issue that [Ivan Kuleshov] sought to rectify with some delicate board-level surgery. Since the original Ethernet jack on the lucky vic^Wrecipient M1 Mac Mini does not have integrated magnetics (magjack), tapping into the appropriate lines would have been rather awkward, with questionable results on the side of the PCB traces that would suddenly be used for PoE purposes they were never designed for.

Rather than choosing this level of experimentation, [Ivan] decided to patch in the Silvertel AG5412 PoE module with plentiful patch wires. This involved removing the Ethernet jack and bypassing the PCB and the magnetics module completely for the new PoE functionality, instead using the magnetics pilfered from a magjack and routing from there back to the mainboard as well as to the PoE module’s inputs. Continue reading “Adding Power Over Ethernet Support To A Mac Mini” →

If Not Ethernet…

June 17, 2023 by 66 Comments

It is hard to imagine today, but there was a time when there were several competing network technologies. There was Ethernet, of course. But you could also find token ring, DEC Net, EcoNet, and ARCNet. If you’ve never dug into ARCNet, [Retrobytes] has a comprehensive history you can watch that will explain it all.

Like token ring, ARCNet used a token-passing scheme to allow each station on the network to take turns sending data. Unlike token ring and Ethernet, the hardware setup was much less expensive. Along the way, you get a brief history of the Intel 8008 CPU, which, arguably, started the personal computer revolution.

Like most networking products of the day, ARCNet was proprietary. However, by the late 1980s, open standards were the rage, and Ethernet took advantage. Up until Ethernet was able to ride on twisted pairs, however, it was more expensive and less flexible than ARCNet.

The standard used RG-62/U coax and either passive or active hubs in a star configuration. The coax could be up to 2,000 feet away, so very large networks were feasible. It was also possible to share the coax with analog videoconferencing.

Looking back, ARCNet had a lot to recommend it, but we know that Ethernet would win the day. But [Retrobytes] explains what happened and why.

If you missed “old-style Ethernet,” we can show you how it worked. Or, check out EcoNet, which was popular in British schools.