"How do i telnet or ssh to the router as standard?"
You cannot.
I'm a dummy and I got telnet access working using this:
1. login to the web gui
2. backup your current configuration => current-conf.bin
3. download this tool =>
http://www.nirsoft.net/utils/router_password_recovery.html (** Win10 will attempt to quarantine the file. It is safe to allow to run)
4. launch RouterPassView.exe (not tested with wine under linux) and open your router config file (ctrl + o) => current-conf.bin
5. go to the options menu and change settings (f3) => text mode - ascii
6. copy your current xml configuration (ctrl + a / ctrl + c) and save it in a new file (ctrl + v) => current-conf.xml
7. insert the description line tweak with telnetd into your xml within the DeviceInfo section
<Description val="Modem Router`telnetd -p 1023 -l login`" />
8.
http://ejs1920.users.sourceforge.net/testing/StatPOSTer-test3.jar launch StatPOSTer-test3.jar, select "TD-W9970" and encrypt your xml file to get the new binary config file => current-conf-with-telnetd.bin
9. login to the web gui and to enable telnetd, use the restore option with this file => current-conf-with-telnetd.bin
you can then telnet <modem_ip> 1023