Chapter 1 System Overview
1-3
Fig. 1.1-1 shows the basic structure of a MAN.
MOADM
MOADM
MOADM
MSTP
MSTP
MSTP
LAN
Router
ATM
Core layer
Convergence
layer
Access layer
Backbone layer
Service and
management
center
MSTP: multi-service transmit platform OADM: metro OADM
Fig. 1.1-1 Basic Structure of MAN
2. Horizontal division
A MAN can also be horizontally divided into the service layer and transmission
layer.
The service layer can implement multiple services such as narrowband voice
service, Internet service, remote calculation and transaction processing,
e-commerce, video conference, multimedia integrated information service,
remote communication and control through computer and leased line service. It
consists of various ATM and IP devices. The transmission layer indicates the
metro optical network that carries the services at the service layer. It provides an
efficient and a unified transmission platform that features large capacity and low
cost and consists of WDM and SDH devices.