TCP/IP Tutorial and Technical Overview - IBM Redbooks

A.4 Generalized Multiprotocol Label Switching (GMPLS)
A.4.1 Benefits
GMPLS extends MPLS into new transmission network types (for example, to
include optical networks).
The optical network is becoming an ideal IP transport infrastructure in core and
metro networks due to its potentially unlimited bandwidth. It is desirable to move
toward a two-layer architecture that transports IP traffic directly over the optical
network because:
► Increased data network complexities are driving architectures that provide
cost-effective and scalable solutions. These solutions must also provide
performance optimization features.
► Challenges include rapid and effective bandwidth provisioning and
protection/restoration. Some of these requirements are addressed by the
MPLS standard. These same business requirements are applicable to the
underlying optical transport network (OTN).
As a result, standards bodies are starting to develop specifications for
incorporating MPLS functions into layer-1 optical cross-connect (OXC) devices
as well as layer-2 transmissions. Standards efforts are addressing the linking of
IP services directly to the optical networks that carry data, allowing these
networks to take advantage of the routing intelligence now embedded in IP
headers.
Note: The focus of GMPLS efforts are mainly in the control plane where new
signaling techniques are described in the GMPLS architecture document
(GMPLS architecture is documented in RFC 3945).
GMPLS provides a common control plane for devices that operate in multiple
domains, such as time-division-multiplexing, packet, or wavelength switching.
The common control plane simplifies operation management through automatic
provision of connections, network resources, and quality-of-service setups.
There are several benefits to extending MPLS functions into optical networks:
► The activity can leverage techniques developed for MPLS to provide a
methodology for real-time provisioning of optical channels. This promotes
faster development of these technologies.
► The outcome can provide a uniform approach to network management for
both data and optical environments. This simplifies overall management
efforts.
Appendix A. Multiprotocol Label Switching 941