300 likes | 428 Views
Joint Techs / APAN. Honolulu Mark Johnson MCNC (NCREN, NCNI, NCLR, …) Mj@ncren.net. How can an R&E network afford to build an advanced network?. Use the obvious strategy of obtaining donations from providers and equipment vendors and the use of grants
E N D
Joint Techs / APAN Honolulu Mark Johnson MCNC (NCREN, NCNI, NCLR, …) Mj@ncren.net
How can an R&E network afford to build an advanced network? • Use the obvious strategy of obtaining donations from providers and equipment vendors and the use of grants • Make more efficient use of the available (scarce) resources - MORPHnet
Production and experimental infrastructure(MORPHnet concept) and their use
What does a user want from an optical network? • An end-to-end path (lightpath) where the endpoints are not defined by the limits of a single carrier’s network
Lightpaths • a lightpath is defined to be a fixed bandwidth connection between two network elements, such as IP routers or ATM switches, established via the optical network • Ietf draft on lightpath attributes
Lightpath attributes • It is assumed that a lightpath will have a number of attributes that describe it such as framing, bandwidth, etc • Canarie asserts that across a given AS a lightpath may be abstracted to look like a single (possibly blocking) cross-connect switch interface.
working examples of Lightpaths • All Optical wavelength on WDM system • SONET channel • Point to point ethernet • ATM CBR circuit • MPLS LSR with defined QoS • Fiberchannel • SMPTE 259 • G.709 (Digital Wrapper)
Problems • Intra-domain • Provisioning of network capacity across network elements within an AS • O&M • Inter-domain • Provisioning of network capacity across multiple AS’s • O&M • In this environment the user has to handle performance and fault management
Lightpath Carrier A Carrier B Carrier C User desires red path but must negotiate and manage provisioning of green, orange, and blue paths
Approaches • Methods of defining, provisioning, and modifying existing services within a management domain • G.ASTN • GMPLS • Methods of linking paths from multiple domains • UCLP • Non-traditional techniques for provisioning capacity between endpoints • OBS/JIT
GMPLS • Generalized MPLS signaling to identify the following path types: • Traditionally statistically multiplexed labeled paths such as ATM or Ethernet • Time division multiplexed paths such as SONET where timeslots are the label • Frequency division multiplexed services such as wavelengths where frequency is the label • Space division multiplexed services such as fibers in a bundle where position in the real world is the label
Division of labor • Control plane • Signaling, routing, Protection /restoration • Transport • Adaptation, Aggregation, Discovery,data integrity, transmission • Management • Management of Faults, configuration/provisioning, accounting, performance measurement, security
Division of labor Network Topology Map Control plane based on IP Routing Topology Policy Constraints Label Forwarding Information base Forwarding plane IP ATM Today Optical Future Drawing poorly copied from Cisco Systems
GMPLS Protocol Diagram LMP RSVP-TE CR-LDP-TE BGP OSPF-TE UDP TCP IP Adaptation Layer ATM Frame Relay SONET Wavelength Switching MAC/GE FIBER
UCLP • Canarie is developing a system including protocols and directories and registration mechanisms Addresses interdomain issues: • Registration of available path components • Directory service for those components • Provisioning of end to end path which could use intra-domain tools such as GMPLS
JIT/OBS view of Optical Network Dilemma • Goal: Lower cost by: • Minimizing OEO • Creating larger transparency islands • But: • Dedicated is overkill (expensive) • Low speed apps. need fine grain mux capability • And: • Existing fine grain multiplexing today requires electronics hence OEO conversion
Gauger et al., “Determining offset times in optical burst switching networks”, COST 266, Zagreb, June 2001. Technology gap • Requires optical buffers • Immature, expensive, low density • Buffers in net lead to complexity • IP is a COMPLEX protocol • Hardware implementations only recently • Creates cost and technology barrier
Optical Cell Switching • TDM dWDM • All wavelengths on fiber switched together • Pluses and minuses • Simpler core network • Need chromatic time correction • Requires frame synchronization • Low utilization of wavelenghts • Lucent is major proponent
JIT Fundamental Values • Low latency is first priority • Tell and go vs. tell and wait • May sacrifice link utilization • JET and Horizon • Aggressive protocol simplification • A pox on buffers (optical delay lines) • Leads to un-necessary protocol and switch complexities • Leads to greater link speed and lower latency • Keep data in optics • No legacy assumptions • Result: high throughput, min. latency and jitter
JIT - OBS Approach • Switched light path network • Large all-optical island • No buffers in data channel • Avoids immature device technology • No buffer overflow in network • Data and signaling channel isolation • Single out of band signaling channel per fiber • Signaling msgs. undergo OEO, processed by intermediate nodes • Network intelligence is concentrated at edge • SIMPLE protocol implemented in hardware
ECOnet • Create a confederation of fiber linked NRT projects: • BOSnet: • MIT Lincoln Labs • dark fiber Boston to Washington DC • ATDNet: • Naval Research Lab (& others) • dark fiber within the Washington D.C. metro area • ECO-South (proposed): • MAX/MCNC/SOX • Dark fiber from Washington to Research Triangle Park and then to Atlanta
East Coast Optical NetworkECOnet MITLL Boston, MA BOSnet MAX/ATDNet Washington, DC ECO-South MCNC/NCREN Raleigh, NC GaTech/SOX Atlanta, GA
Illustrates need to evaluate Entire system • Fiber, amps, DCUs, maintenance and Rent can become dominant costs
NCNI WDM Network Duke DCU 15454 Node DCU Network Management Access UNC DCU DCU Cisco RTP MCNC MCNC Dispersion Compensation Unit DCU DCU DCU NCSU RLGH EDFA amplifier • Engineering Notes: • Ring Circumference = 178.1099km • SMF-28 Fiber SMJ 5-27-03