From reading that I see L3 switching uses "specialized ASICs with the help of content-addressable memory" and later on features "flow accounting". I'm supposing those primitives could make a rate limiter. I'm refusing to go down this rabbit hole though. If I'm wrong I'm sure I'll hear about it by tomorrow :)
Respectfully, you are incorrect. Switches, in the technical sense and accepted terminology, refers to Layer 2 processing. Routing is Layer 3. And so on. MLS is just a combined product offering multiple Layers of processing.
I think this argument can never be won. "Layer 3 switch" is common terminology. But "switching" strictly speaking is a Layer 2 action. But sometimes we say that a switch is "switching packets at Layer 3" when it is doing a hardware action in response to IP layer information. We could go back and forth all day. So let's all be reasonable if possible.
I believe “L3 switch” and routers(L3-L7) are distinguished by architecture; L2 and L3 switches employ non-programmable “packet switching fabric” ASIC with CPU acting as a control system, while routers are generally a general purpose computer optionally with non-Turing-complete ASICs for faster packet processing.
Expectations of a “switch” is therefore that it’s not a dual core PowerPC box with 24-96 GbE ports on PCIe, running outdated Linux Kernel, and that it can’t do what such a bare metal box could do.
I'm not sure what is non-programmable about the packet switching fabric. It can be programmed to switch packets, which is what we want the device to do. It can also be programmed to route packets, which is done at the same rate as switching them (usually line rate). So we can call this "layer 3 switching" because it is the same process as the L2 switching but it is happening at L3. That's what a L3 switch is and does.
It can't do the same as a box with general purpose CPU, but it can do the thing you bought it for (routing) at line rate (hence the comparison to switching).
My Brocade FCX 648S-HPOE arrived from eBay yesterday.
See I have a homelab setup I'm cobbling together and a mission to train a door to recognize and block my neighbor's cat from entry. Her name is Aria and she pisses everywhere then eats the cat food. I have 3 cats that require free use of the cat door, and if its closed they piss everywhere.
I've been scheming about how to do this for quite some time. The basic idea would be to install a magnetic lock on the cat door, and actuate it over an MTQQ triggered relay. But how to trigger it? My cats refuse to wear collars and their microchips weren't readable within usable proximity. Enter https://frigate.video/ this summer. Its a self-hosted NVR that can be trained to recognize arbitrary objects and fire off events when objects are detected, including to MQTT. It looked like a viable project, and I've been trying to get some camera system anyways for minding the front door while I work from a distant basement- but I haven't been willing to join the Ring panopticon just yet.
Over the past few months I've been acquiring the required hardware from eBay. I overpaid for a Google Coral USB TPU, and got a steal on a pair of their recommended cameras, Loryta IPC-T5442TM-AS-LED unused from a commercial install job. Unfortunately they are POE only, or a propriety 12VDC. I know I was going to need POE eventually anyhow, and while my Mikrotik RB4011iGS+5HacQ2HnD has a single POE port I would need more - and I wasn't able to get even that port working for one reason or another. So I found a Brocade FCX 648S-HPOE for $50. Overkill? Most definitely. I thought there would be no harm, and it would give me an opportunity to work with serious gear and improve my networking acumen. It is as loud as a laundry machine I swear.
Unfortunately its so serious that I need to go find an RS-232 cable to enable web management - until then it drops all links. So I still haven't been able even fire up the cameras. If my foraging through the cable bins again proves fruitless, then I'm going to their drive around town or find one online and wait until the next weekend...
So that Best Buy home equipment sounds kinda nice right now.
The Brocade FCX 648S-HPOE has is a stackable switch with forty four 10/100/1000 Mbps ports plus four Combo ports, which include four 10/100/1000 Mbps RJ45 ports and four 100/1000 Mbps SFP ports. The switch has two management interfaces, a DB9 serial port (Console) on the front panel and an RJ45 port (Out-of-band Management Interface) on the rear panel
A layer 3 switch does not just “glean” information from the packet , it can switch packets and rewrite IP header data at wire speed to place packets on different networks completely bypassing a router.
I don’t know of any better term for it than a “layer 3 switch”.
https://en.wikipedia.org/wiki/Multilayer_switch
See for an intro.