AirLink® XRルーターでUSBを使ってできることとは？

USB 3.1がリリースされて以来、ネットワーク、電源の入出力、ディスプレイの接続、コーヒーを淹れる以外のあらゆる機能をサポートするアダプターにUSBを使用するなど、USB機能が爆発的に向上しました。イーサネットポートのないノートパソコンが一般的になり、USBポートのみのノートパソコンもあります。店舗の棚（実店舗やバーチャル店舗）には、アダプターがずらりと並んでいます。セルラールーターもこの変化の一部であり、SemtechのAirLink® XRシリーズなどの高度なモデルにはUSB-Cポートが搭載されています。

このブログでは、SemtechのAirLink® XRシリーズのProルーターのUSB-Cポートの潜在的な用途について掘り下げます。 

Our previous-generation routers had the ability to do network over micro-USB but it was really more for diagnostics and troubleshooting than anything else. As USB technology has evolved, so too have our routers, and this evolution continues. 

The XR80 and XR90 models feature a single USB-C port that provides local area network (LAN) connectivity at USB 3.2 gen 1 speeds, up to 5 Gbps. To actually experience that level of throughput you’d need a pretty sophisticated setup with all high-speed interfaces — including storage systems —and that’s not likely to be commonplace anytime soon. The point of saying “up to 5 Gbps” is really more about giving you assurance that the port won’t be a throughput bottleneck. Both the XR80 and XR90 have a 5 Gbps RJ45 network port and the key takeaway is that the USB-C port can handle the same sort of extreme data throughput as the 5 Gbps “Ethernet” (RJ45) port. 

So the next question is probably going to be around what you would do with the USB-C network connection. Similar to the older micro-USB ports on previous router generations, it can be used for diagnostics. You can use it for a local connection to configure, load a template or do local software upgrades. You can access the AirLink OS UI just like you would on the RJ45 Ethernet ports, and you still require user authentication to do anything with the router. 

And sometimes, you just need another network interface when you run out of RJ45 ports. You could use it as a regular LAN access port and can connect it to a different network segment if needed. You could have different LAN segments for specific Ethernet ports, for USB-C port, for different Wi-Fi SSIDs and isolate or bridge them to meet your requirements. 

With the new AirLink XR60 5G router, the USB-C capabilities have evolved one step further to include power delivery.

Power delivery is a very broad topic for USB-C and the devil is in the details: Does it serve as an input to power up the router, or as an output to provide power to accessories or client devices?  
Initially, for the XR60, the USB-C port only supports input power. This means you can power up the router with its traditional Molex power (7-36VDC) or you can use a laptop-class USB-C power adapter. And if you want redundant power, it will do that too: the XR60 will use the Molex-based DC power as long as it is sufficient for operation, and if the voltage dips too low, the router will reboot using the USB-C power to resume operation.  

It is important to note that the addition of power delivery (input) doesn’t compromise the high-speed network capability. I’ve been using USB-C cables to provide network links for MacBooks, tablets and USB-C laptops. For MacBooks, the process is as simple as plugging in the cable; no additional drivers are needed. For Windows 10 and 11 PCs, you need to install a driver (available through Microsoft Update catalog) to enable the great high-speed network connection — which sometimes is just what you need!