Trunk interface module – ZyXEL Communications Multi-service Access Platform MSAP2000 User Manual
Page 59

4. System Components
MSAP2000 Technical Manual V3.0
4-8
4.5. Trunk Interface Module
MSAP2000’s Trunk Interface Module uses copper wires, optic
fibers, or wireless transmission, to connect the COT and RT.
Based on usage of different technologies, the Trunk Interface can
be divided into two types: TDM and IP. QE1M and OIM (STM-1
Optical Interface) are TDM technology based, while GbE (Gigabit
Ethernet) is IP technology based. The Trunk Interface Module is
installed within the Main shelf, and multiple trunk interfaces can be
installed, based on different application purposes. QE1M and
OIM both support 1+1 Protection Switch mechanisms; the
System’s backplane wiring setup will not be affected by different
trunking methods.
Module
Slot No.
Line Capacities
Note
OIM/SM1
1 ~ 18
1890 DS0
SM4
1 ~ 16
7560 DS0
1+1, & Ring
Protection
Switching
QE1M
1 ~ 16
120 DS0
1+1
Protection
GSH
1 ~ 16
36 DS0 (*depends on
loop quality)
M-Bonding.
QEToP
1 ~ 16
120 DS0
1+1
Protection
GbE
18
1 Gbps
Supports 756
ADSL
OIM/SM1/SM4
OIM/SM1 is a STM-1 optic interface module and SM4 is a STM-4
optical interface module, which conforms to ITU-T G.957
standards. With OIM/SM1/SM4, MSAP2000 can form various
network topologies, such as Point-to-Point, Star, Linear, Tree and
Branch, and Ring. Total number of OIM/SM1/SM4 modules can
be up to 10 when used in star configuration on one shelf with
redundancy in consideration. OIM/SM1/SM4 provides automatic
protection switch functions, such as 1+1 Protection Switching for
Star topologies, and Protection for Ring topologies.
OIM/SM1/SM4 also supports enforced protection switching
mechanisms. The switch time is under 50ms, and ongoing
services will not be interrupted during switching.
GSH
When GSH is provisioned as the trunk interface for the DSL
pair-gain application, the M-bonding for the capacities expansion
is also provided. The remote power feeding option for 120~ 180V
is also provided and the concentration to allow more number of
subscribers. In low-density usage, other than MSAP2000 system
shelf, a small form factor shelf to allow poll or wall mounted to
work with GSH trunk.
QE1M
QE1M is a MSAP2000 trunk interface, which connects the COT
and RT by copper wires. QE1M conforms to 2,048 Kbit/s ITU-T
G.703/G.704/G.706 interface standards and can be connected to
external microwave radio equipment where optic fibers are yet to
deployed or impossible to lay. The total number of QE1M for a
single shelf can be up to 16 for both trunk and service interface.