G.8261

ITU-T standard G.8261 is one of the organization’s recommendations defining various aspects of Synchronous Ethernet (Sync-E). As packet-switched networks (PSNs) are asynchronous by nature, they introduce inaccuracies such as packet delay variation (PDV) and packet loss. As a result, synchronization – a crucial factor in cellular networks – has become the biggest challenge in the migration to packet-switched networks. Synchronous Ethernet uses the Ethernet physical layer to accurately distribute frequency with clock mechanisms similar to those of SDH/SONET. As Sync-E is a link-by-link frequency distribution scheme, it requires the entire clock distribution path (i.e. all the network nodes involved) to be Sync-E compliant. G.8261 specifies the acceptable limits of jitter and wander for packet networks and equipment at the network boundary’s TDM interfaces, as well as the minimum requirements for the synchronization function of network elements. RAD is the contributing author of many packet timing and synchronization standards, among which is ITU-T G.8261.

RAD’s G.8261 Solutions

RAD has created the SyncToP platform of high-performance clock recovery and distribution techniques with powerful frequency, phase and TOD alignment capabilities. These are incorporated into a variety of PSN access gateways and demarcation devices, such as the ACE-3220 and ETX-204A, to ensure reliable transmission of 2G, 3G and 4G traffic without the need for costly dedicated hardware.