Jednoduchý klient

require "net/telnet"
timeserver = "www.fakedomain.org"

tn = Net::Telnet.new("Host"       => timeserver,
                     "Port"       => "time",
                     "Timeout"    => 60,
                     "Telnetmode" => false)
local = Time.now.strftime("%H:%M:%S")
msg = tn.recv(4).unpack('N')[0]
# Conver to epoch
remote = Time.at(msg - 2208988800).strftime("%H:%M:%S")
puts "Local : #{local}"
puts "Remote: #{remote}"