Not a local network, but localhost example: due to the lousy private certificate capability APIs in web browsers, this is commonly used for signing with electro

Not a local network, but localhost example: due to the lousy private certificate capability APIs in web browsers, this is commonly used for signing with electronic IDs for countries issuing smartcard certificates for their citizens (common in Europe). Basically, a web page would contact a web server hosted on localhost which was integrated with PKCS library locally, providing a signing and encryption API. One of the solutions in the market was open source up to a point (Nowina NexU), but it seems it's gone from GitHub For local network, you can imagine similar use cases — keep something inside the local network (eg. an API to an input device; imagine it being a scanner), but enable server-side function (eg. OCR) from their web page. With ZeroConf and DHCP domain name extensions, it can be a pretty seamless option for developers to consider.