On the IETF standardization opportunities for sub-wavelength optical networks

1. On the IETF standardization opportunities for sub-wavelength optical networks Juan Fernández-Palacios Telefonica I+D, Madrid, Spain

2. Motivation, problem area • Photonic sub-wavelength technologies are being developed by multiple vendors as a suitable solution for Metro Area Networks (MAN) • Many Optical packet switching (OPS) and optical burst switching (OBS) technologies and architectures have been proposed to support sub-wavelength services • However, photonic sub-wavelength standardization is just starting

3. Steps already taken 1.- First IETF draft on GMPLS Framework for subwavelengths March 2011 2.-IETF recommeneded to start data plane standardization at ITU-T 3.-First ITU contribution on standardization plans for subwavelengths. December 2011 4.- ITU contribution on common terminolgy expected by. September 2012

4. Standardization Status • Architecture and terminology • Control Plane IETF Network Working Group ITU-T SG15 Question(s):12/15 Working Document: Terminology for Sub-Lambda Photonically Switched Network (SLPSN) Internet Draft: O. González de Dios, G. Bernini, G. Zervas, M. Basham, “Framework for GMPLS and path computation support of sub-wavelength switching optical networks“, draft-gonzalezdedios-subwavelength-framework-00.txt

5. Terminology for Sub-Lambda Photonically Switched Network (SLPSN) • SLPSN definition: SLPSN is a switching technology which handles, at the data plane level and in a photonic way, temporal slices of individual or multiple wavelengths. SLPSN incorporates the optical time domain in addition to the wavelength/frequency and space domains. • SLPSU definition: a sub-lambda photonic switching unit (SLPSU) is an optically sliced unit of a wavelength in time domain, such as an optical time slot, an optical burst, or an optical packet.

6. Terminology for Sub-Lambda Photonically Switched Network (SLPSN) • SLPS network has two types of node functionality: • Edge nodes are hybrid (electric and photonic data planes) in charge of assembling data coming from different sources (i.e. IP, CBR, Ethernet …) which are sent to an optical circuit, burst or packet and vice-versa. • Core nodes have to deal with contention, scheduling, routing and QoS policies in an all optical environment (traffic inside the core node data plane is only composed by photonic flows): note that the control plane is generally processed at the electronic level.

7. GMPLS extensions for SLPSN: MAINS approach

8. GMPLS extensions for SLPSN: MAINS approach • Provide specific routing and reservation procedures to support the sub-wavelength switching granularity • end-to-end sub-wavelength network connections setup and management • sub-wavelength aware route computations • built on top of the GMPLS architecture specified by IETF and ITU-T ASON project • The control of the transport plane is implemented through a vertical cooperation with the underlying custom control procedures of different subwavelength technologies • The subwavelength network resource are modeled to enable the definition of GMPLS signaling and routing protocol extensions • new object formats for announcing and discovering sub-wavelength network resource availabilities • new object formats for reserving sub-wavelength network resources • The MAINS GMPLS can be interfaced with standard GMPLS instances running in neighbouring domains (e.g. core/backbone segments of the network) • Multidomain routing compliant with IETF hierarchical PCE model • Multidomain signaling compliant with the IETF call signaling approach

9. Path Computation for SLPSN • Two alternatives are considered: • Multidomain OSPF over E-NNI preferred option • Hierarchical PCE: PCEs exchange information about their network topologies PCE ROADM ROADM ROADM ROADM ROADM ROADM ROADM ROADM ROADM OSPF OSPF PCE E-NNI PCE OSPF PCE ROADM ROADM E-NNI ROADM ROADM ROADM ROADM Subwavelength domain. Vendor A Subwavelength domain. Vendor C OTN/WSON domain. Vendor B Hierarchical PCE: This option reduces OSPF traffic, supports different routing protocol implementations in each domain (e.g OSPF proprietary extensions) and allows networks operators to select the optimum e2e algorithm for their networks

10. Resource modelling and abstraction for SLPSN

11. Resource modeling and abstraction for SLPSN • Standardization is starting at ITU-T: common terminology and architecture • Control plane standardization opportunities at IETF comprise: • GMPLS extensions to announce and discovery aggregated and summarized subwavelength resource availabilities, and to reserve subwavelength resources in the metro network. • Vertical ccoperation between MPLS CP and Subwavelength CP • Multidomain-Multiregion control plane interworking • Common resource modeling and abstraction for any kind of subwavelength technology

12. Acknowledgement • The research leading to these results has received funding from the European Union's Seventh Framework Programme ([FP7/2007-2013] [FP7/2007-2011]) under grant agreement n° [247706], MAINS.