|
Feature Name |
Release Information |
Description |
|---|---|---|
|
OLT Based Omnidirectional Add/Drop Topology |
Cisco IOS XR Release 7.9.1 |
You can now set up pure OLT-based omnidirectional add/drop topology. This topology is supported over the C+L band and scalable beyond 4-degree nodes. Dual omnidirectional add/drop can be implemented on a node to provide redundancy or increased add/drop capacity. The omnidirectional setup provides the flexibility to the multidegree topology to route channels through any of the optical degrees during fiber cut without the need for physical fiber reconnections |
You can design multiple OLT-based omnidirectional add/drop stages. This configuration gives flexibility to the multidegree topology to route channels through any of the optical degrees during fiber cut without the need for changing the physical fiber connections.
NCS2K-MF-4x4-COFS based colorless omnidirectional topology
In Release 7.7.1, the omnidirectional add/drop stage is designed using the NCS 2000 passive module, 4x4 colorless omnidirectional flex spectrum (COFS) add/drop module (NCS2K-MF-4x4-COFS) and NCS2K-MF-MPO-8LC. The channels from different degrees are aggregated at the MF-MPO-8LC. The MF-4x4-COFS adds the channels. Similarly, the channels from the MF-4x4-COFS can be routed to any of the degree through the MF-MPO-8LC, thus achieving the omnidirectional functionality. This colorless omnidirectional topology gives flexibility to retune the frequency or wavelength of the channel coming from the transponder or muxponder without any physical changes.
Topology components
To build this topology, you need these hardware:
-
NCS 1010 OLT devices
-
NCS2K-MF-4x4-COFS modules
-
NCS2K-MF-MPO-8LC modules
-
NCS1K-BRK-8 modules
These are the specific cable configurations for interconnecting the modules:
-
The MF-4x4-COFS modules are interconnected using standard MPO 8 or 12 fibers (15454-MPO-MPO-x or ONS-12MPO-MPO-x )
-
The MF-4x4-COFS modules and NCS1K-BRK-8 module are interconnected using standard LC-LC fibers.
Limitations
-
This configuration is supported only for C-band ROADM.
-
This configuration is scalable only up to a maximum of 4 degrees. More OSNR penalty is induced by the MF-4x4-COFS as you add more degrees.
-
One MF-4x4-COFS module can support up to only four channels. To scale up to 32 channels, you would require 8 MF-4x4-COFS modules.
-
The terminal node in this configuration can be connected only to NCS 1004 line cards, line cards with CFP2-400G-DCO as a trunk interface, and DP04QSDD pluggable.
OLT based omnidirectional add/drop topology
From the Release 7.9.1, the omnidirectional add/drop stage is implemented using two OLT-C nodes interconnected back-to-back at the LINE-TX/RX ports. You can have more than one omnidirectional add/drop stages in one ROADM site. You can also include OLT-L devices in this topology. Multiple transponders can be connected to the terminal OLT node including the low-power ZR+. There are no additional restrictions on the transponder or interface types that can be connected to the terminal OLT-C.
Topology components
To build this topology, you need these hardware:
-
NCS 1010 OLT-C devices
-
NCS 1010 OLT-L devices
-
NCS1K-BRK-24 modules
-
NCS1K-BRK-8 modules
-
NCS1K-MD32-C modules
These are the specific configurations and applications that are required for this configuration:
-
The interconnection between the terminal OLT-C, where the traffic is terminated and the omnidirectional degree is managed as a 0dB span.
-
OSC-C and OSC-L controllers can be used with unnumbered IP on OSC interfaces of the omni span.
-
Link tuner and Gain estimator must be disabled on the Omni span.
-
APC must be enabled on Omni span.
-
ASE loading is enabled (both static and dynamic).
-
Specific configuration for optical applications such as span length and fiber type are not required.
-
To have the Preamplifier of OLT-C working in proper condition (minimum gain 12dB), the Line-Tx PSD must be set to –12.9 dBm/12.5 GHz (considering 80% CH_SD).
