13.3.6 Enterprise E1/T1 Unified Access Service (OLT Cascading)
ONUs access enterprise TDM service in E1/T1 access mode, and transmits the data to the SDH
network in OLT cascading mode over the GPON network which supports long-distance
transmission and high bandwidth. In this way, uniform deployment of E1/T1 service is achieved.
13.3.6.1 Service Requirement and Application Scenario
Service Requirement
l
Existing SDH resources are utilized efficiently. In this way, carriers' existing investments
are protected and enterprise users in different regions are won.
l
Services are received over optical fibers, reducing investment in copper cables between
enterprises and the SDH network.
l
The standardized user-side ports facilitate deployment and maintenance.
Application Scenario
, a carrier's SDH network is migrated gradually. In a city, there are
only some nodes (for example, OLT_A in the following figure) can transmit signals upstream
to the SDH network through STM-1 ports, and other nodes (for example, OLT_B in the following
figure) must access SDH resources through GE/10GE ports. In this scenario, ONU_B accesses
the E1/T1 service in SAToP mode, and transmits the service to the OLT at the local site (OLT_B)
over the GPON line. OLT_B transparently transmits the service to another OLT with SDH
resources (OLT_A) through GE/10GE ports.
l
For carriers, with this networking, they can win enterprise users who have no SDH resources
with GPON lines which support long-distance transmission and high bandwidth. With the
trend of fiber-in and copper-out, deployment of GPON lines can reduce deployment costs
of copper cables and support service expansion.
l
For enterprise users, with GPON access, they can reduce fees spent in leasing lines.
Figure 13-21
E1/T1 access in SAToP mode (OLT cascading)
SDH
E1/
STM-1
OLT_A
Splitter
E1
TDM
E1
SAToP
OLT_B
ONU
Enterprise
Splitter
E1
TDM
E1/
STM-1
L2
G
E/
10
G
E
SmartAX MA5600T/MA5603T/MA5608T Multi-service
Access Module
Commissioning and Configuration Guide
13 FTTO Configuration (Large-sized Enterprise Access)
Issue 01 (2014-04-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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