User's Manual

VOLUME II, CHAPTER 1, SYSTEM OVERVIEW
Protection Options
Eclipse supports link, interface, network, and platform protection options:
Link/Path Protection
Hot-standby, space diversity, or frequency diversity options are supported.
Rx voting is hitless/errorless; Tx switching is not hitless. The maximum restoration
time for a Tx switch is 200 ms.
A remote Tx switch is forced in the event of a silent Tx failure.
Interface Protection
DS1, DS3 and OC3 interfaces can be hot-standby protected using paired (stacked)
DACs.
The protectable DACs are DAC 16x V2, DAC 3xDS3, DAC 3xDS3M, DAC 2x155o,
DAC 2x155e, DAC 155oM.
When a switch occurs, all Tx and/or Rx tributaries are switched to the protection
partner.
Two protection configurations are supported, tributary protection, and always-on:
Tributary Protection
l Y cables connect the paired DACs to customer equipment.
l In the Rx direction (from the customer) both DACs receive data, but only the
online
Rx DAC sends this data to the TDM bus.
l In the Tx direction, the online Tx DAC sends data to customer equipment, the
other mutes its Tx line interface.
Tributary Always-On
l Separate cables connect each DAC to customer equipment.
l In the Rx direction (from the customer) both DACs receive data, but only the
online Rx DAC sends this data to the TDM bus.
l In the transmit direction both DACs send data to customer equipment, and
the customer equipment switches between these two always-on tributaries.
Protection switching is not hitless. The maximum restoration time for a Tx or Rx trib
switch is 200 ms. Typical restoration times are between 80 ms and 120 ms.
30 AVIAT NETWORKS