Abstract: An apparatus and method provide non-intrusive in-service testing of audio/video synchronization testing without using traditional audio marker tones. The network includes an A/V synchronous test signal generator which injects video and audio markers into the video and audio non-intrusively and routes the two signals into a switch where they are switched into a channel for encoding and transmission via the ATM network. At the distant end the signal is decoded and routed by a switch into the A/V test generator and measurement set where the markers are detected and the A/V skew calculated, after which the audio and video are routed to the subscriber. The A/V test set signal generator includes a Video Blanking Interval (VBI) test signal generator and a white noise generator, the former injecting a marker into the video signal and the later injecting an audio marker into the audio signal.

Abstract: A system and method prevent unauthorized users and devices, in a dynamic user/device environment, from obtaining access to shared-medium public and semi-public IP networks. A network includes a layered communication system and routers/switches for coupling users and devices to a Dynamic Host Control Protocol (DHCP) server and an authentication server. Databases support the servers. The network incorporates Address Resolution Protocol (ARP). Authorized users and devices register for service by providing the DHCP with user identification for log-in, passwords, MAC addresses, etc. When users connect to the network access point, a DHCP exchange is initiated to obtain a valid IP address and other associated parameters. The DHCP client initiates a MAC broadcast for IP addresses which contain in the request the end user's device MAC address. The associated router switch will pick up and forward to a DHCP server the end user's device request.