363-206-285
Administration and Provisioning
8-12 Issue 3 June 2001
DS3 to OC-3/OC-12 8
The DS3 signal maps directly to an STS-1 via the asynchronous mapping. The
STS-1 signals are byte-interleaved to form an STS-3 or STS-12 signal. Finally, the
STS-1, STS-3, or STS-12 is converted to an optical OC-1, OC-3, or OC-12 signal,
respectively.
In the opposite direction, a received OC-1, OC-3, or OC-12 is converted back to
an electrical signal and, for OC-3 and OC-12, demultiplexed to STS-1 signals. A
DS3 signal is recovered directly from its STS-1.
The DS3 signal maps directly into the STS-1 payload. The DS3 location is
mapped into the STS-1 in the OC-3. For example:
atom-1
btom-2
ctom-3
btoc-2
EC-1 to OC-1/OC-3/OC-12 8
The STS1E low-speed interface receives an EC-1 signal from the backplane
coaxial connector which is then routed as an internal STS-1. This signal can be
STS-1 or VT1.5 cross-connected to the OC-1, OC-3, or OC-12 interface. Three
internal STS-1 signals are multiplexed into an STS-3 or STS-12 and converted to
an optical OC-3 or OC-12 signal.
In the opposite direction, a received OC-1, OC-3, or OC-12 is converted into an
electrical STS-1, STS-3, or STS-12 and demultiplexed. After either STS-1 or
VT1.5 cross-connections, the resulting STS-1 internal signal is converted to an
EC-1 signal by the STS1E interface. The STS1E interface can support both
STS-1 and VT1.5 cross-connections. The following are examples of STS-1 cross-
connections:
atom-1
btom-3
ctom-2
The following are examples of VT1.5 cross-connections:
a-1-1 to m-1-1-1
a-7-4 to m-1-1-2
b-1-1 to m-2-1-1