Patent ID: 8724659

Claim:
A forwarding unit for receiving Ethernet packets and forwarding information therein on a digital subscriber line, said forwarding unit comprising: a device for producing a clock signal, said device including: a selection unit for selecting at least one stream of received Ethernet packets, wherein the selection unit includes a general analyzing unit for analyzing received Ethernet packets to find a stream of packets from one destination to one user, the packets carrying real time information belonging to a real time service; and a clock signal generating unit for generating a reference clock signal according to arrival times of packets in the selected at least one stream, wherein the clock signal generating unit includes a delay determining unit for determining the delays of arrived packets in relation to the reference clock signal, wherein the delay determining unit includes: a signal generator providing a first clock signal having a frequency; a delay measuring counter configured to receive a signal obtained by dividing the first clock signal by a set number and to count the pulses of the received signal modulo a first number of times; and a measuring unit connected to the counter for determining, as a measure of the delays of the packets in relation to the reference clock signal, the counter value for the arrival time of each of the packets of the selected stream delays; and a modem connected to the digital subscriber line and to the clock signal generating unit, said modem including a Network Timing Reference (NTR) unit for receiving the reference clock signal for use in transmission of voice information to the digital subscriber line.