Requirements for GMPLS-Based Multi-Region and Multi-Layer Networks (MRN/MLN)

Abstract

Status of This MemoThis memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. AbstractMost of the initial efforts to utilize Generalized MPLS (GMPLS) have been related to environments hosting devices with a single switching capability. The complexity raised by the control of such data planes is similar to that seen in classical IP/MPLS networks. By extending MPLS to support multiple switching technologies, GMPLS provides a comprehensive framework for the control of a multi-layered network of either a single switching technology or multiple switching technologies.

Generalized MPLS (GMPLS) Protocol Extensions for Multi-Layer and Multi-Region Networks (MLN/MRN)

“…In the MRN context, nodes that have at least one interface that supports more than one switching capability are called hybrid nodes [RFC5212]. The logical composition of a hybrid node contains at least two distinct switching elements that are interconnected by "internal links" to provide adjustment between the supported switching capabilities.…”

“…A virtual TE link is defined as a TE link between two upper-layer nodes that is not associated with a fully provisioned FA-LSP in a lower layer [RFC5212]. A virtual TE link is advertised as any TE link, following the rules in [RFC4206] defined for fully provisioned TE links.…”

“…The rationales and requirements for MultiLayer/Region networks are set forth in [RFC5212]. These requirements are evaluated against GMPLS protocols in [RFC5339] and several areas where GMPLS protocol extensions are required are identified.…”

Evaluation of Existing GMPLS Protocols against Multi-Layer and Multi-Region Networks (MLN/MRN)

“…For example, LSC, TDM VC-11 and TDM VC-4-64c are three different layers. [RFC5212] defines a Multi-Layer Network (MLN) to be a Traffic Engineering (TE) domain comprising multiple data plane switching layers either of the same ISC (e.g., TDM) or different ISC (e.g., TDM and PSC) and controlled by a single GMPLS control plane instance. [RFC5212] further defines a particular case of MLNs.…”

“…[RFC5212] defines a Multi-Layer Network (MLN) to be a Traffic Engineering (TE) domain comprising multiple data plane switching layers either of the same ISC (e.g., TDM) or different ISC (e.g., TDM and PSC) and controlled by a single GMPLS control plane instance. [RFC5212] further defines a particular case of MLNs. A Multi-Region Network (MRN) is defined as a TE domain supporting at least two different switching types (e.g., PSC and TDM), either hosted on the same device or on different ones, and under the control of a single GMPLS control plane instance.…”