Research firm, Heavy Reading, defines “P-OTS as a platform that combines SONET/SDH, connection-oriented Ethernet, DWDM and, depending on where the platform is used within the network, also optical transport network (OTN) switching and reconfigurable optical add-drop multiplexers (ROADMs)”
As per Heavy reading, there is a growing trend now, with more and more operators asking about IP/MPLS capabilities in P-OTS platform. Transport groups inside operators have expressed their interest to add layer 3 functionality to P-OTS platforms. Operators favor integrating L0 to L3 in P-OTS platform so that one platform can meet all their needs. This new requirement is addressed in P-OTS 2.0. According to Heavy Reading, there are four differentiating features of P-OTS 2.0 compared to legacy P-OTS.
- There is change of focus from TDM to packet functions.
- Pure packet implementation of P-OTS is ramping up.
- 100G is seeing more applications in metro area
- Switched OTN has entered Metro area, removing the need of SDH fabric in new network elements.
Looking at what is present in the market today; the P-OTS platforms leave a lot to be desired. It would be hard to find a product optimized for all layers. Legacy P-OTS platforms are optimized for certain applications but not for all. Depending on where the vendor is coming from, some P-OTS platforms are optimized for TDM applications but not for ethernet applications. Some are strong in DWDM but not in packet and TDM. Some vendors position to carry Ethernet over OTN; still others vouch that carrying Ethernet in native form is better and keeping OTN as option on P-OTS platform. P-OTS, thus, has become more of a marketing term rather than the platform that can address all the needs, desired for such platforms.
P-OTS 2.0, therefore, should be able to address all layers (layer 0 to 3) effectively and in optimized way. Operators would not like to have platforms (similar to P-OTS) that are geared and focused on few applications and leaving the others as just “supported on platform”. P-OTS platform shall be modular and platform based preferably supporting a family of platforms for applications from metro to core. Cards should be interchangeable between platforms. The platforms should support IP/MPLS but above all GMPLS across Layer-0 to Layer-3. Again it should be possible to run all layers independently or all layers run tightly together, seamlessly. The layers should communicate with one another, for example, for fault management. These are the needs of the operators today and vendors ought to rise to this occasion.