1. Reconfigurable OADMs Reconfigurable OADM (ROADM)
A reconfigurable network has 2 key elements:
ROADM or Reconfigurable Optical Add/Drop Multiplexer for selective adds and drops of wavelengths. A wavelength is the virtual dedicated link that is part of a leased network that a telecom provider will sell and exchange with a number of different customers. Having reconfigurability allows reuse as customers exchange or add services.
Simple add and drops of from 4 to 32 or more wavelengths are the largest market comprising about 90% of wavelength switching applications. Xtellus’ Wavelength Blocker is the ideal solution.
The other key requirement is Ring Interconnect. Currently ring interconnect is done after conversion to an Electrical signal. A future desire is for direct optical ring interconnect to save the cost of optical to electrical to optical conversion.
Xtellus has an upgrade path to a Wavelength Selective Switch, which is the product that would address ring interconnect. This market is further in the future because of complex network issues.

2. ROADM basic functions ROADM basic functions The result is:
Add, Drop, Block or Attenuate any wavelength in any node – controlled by remote management
Power monitoring and equalization of any wavelength
In Multi-Degree units every port can be configured for single wavelength or any size band of waves.
The result is:
Fully flexible transport networks
Hitless networks upgrades and changes
Full power monitoring and control
SAVE on spares
SAVE on OPEX
Fast time to market

3. Static versus Reconfigurable OADM
Node 5
Node 1
Node 2
Node 4
Node 3 OA
Fixed wavelengths
network
Node 8
Node 9
Node 1 OA OA
Tunable
network
Node 5
Node 2
Node 3
Node 4

4. MRV ROADM Architectures
LD1600 double “long” slot size modules. For East-West configuration, 4 “long” slots are allocated for ROADM.
2 degree (East-West only) 40 ports Mux/Demux – availability Q4/2006
Fixed wavelengths on filter ports (40)
No multiplex fiber solution for ring-ring interconnect
Multi-Degree (1x9 WSS switch) – availability Q2/2007
9 Add/Drop ports
eliminates add/drop filters
Fully tunable drop ports (single wavelength or multiplex section)
Enabler for ring to ring or mesh network designs

5. LD1600-ROADM40 structure 2 x 1 switch VOA Power Monitor
2 x 1 switch
VOA
Power Monitor
Insertion losses
COM IN-DROP = 11
ADD-COM OUT =8
COM IN-EXP OUT=2.5
EXP IN-COM OUT=12
DROP

6. East-West ROADM system configuration
12db
2.5db
8db
11db

7. Designing with 2-degree ROADM
+2dbm
-18dbm
-13dbm
+2dbm
+2dbm
ROADM
ROADM
20db
ROADM
ROADM
All channels
Are attenuated
To mach PassThrough
traffic
0dbm
Every node looks the same and acts the same
At each Booster Output ALL channels have the same +2dbm (due to 40 waves) power