Router a Shared Device?

iMac (Retina 5K, 27 inch, Late 2014)

Processor 3.5 GHz Intel Core i5

Memory 8 GB 1600 MHz DDR3

HDD 1 TB Fusion drive

macOS High Sierra version 10.13.4

I recently moved to fibre broadband and got a new router (which I 've connected by Ethernet). My ISP is a UK company called Plusnet and the router is called Plusnet Hub 1 (pnhub1). In my Finder sidebar the router has appeared as pnhub1 under the "Shared" title. Why is this? In what way is it a shared device? NB: the router appears to be working ok since my connection to the internet is fine.

Also, when I click on the router in the "Shared" list, then near the top of the main Finder window it says "Connection Failed". When I click on the "Connect As..." button a message appears saying I am attempting to connect to the server "pnhub1". I enter my name and password, but cannot connect.

Does anybody know what is going on? Am I losing some functionality of some sort?