Setting up pam module:

add to to common-auth this line:
auth	required	pam_uds.so	base=http://192.168.0.30/nss

Setting up nsswitch module:

1.- Copy libnss_uds.so.2 to /usr/lib
2.- Edit /etc/nsswitch.conf, and put:

passwd:		compat uds
group:		compat
shadow: 	compat

host:		files dns
networks:	files
protocols:	files
services:	files
ethers:		files
rcp:		files

netgroup:	files

(look passwd file, rest is sample content)

3.- Create /etc/uds.cfg file, that hast the BASE url of the auth provider
example:
https://192.168.0.30/nss


Every connection takes about 2.5 Mb, so with 380 Megas default machine memory size, we have for 100 connections (the 100Mb of "plus" is for OS)

So, machine memory should be 128 + 2.5 * Expected concurrent connections.

No limit has been detected, every connection spawn a process on server, but no data has been collected so far.