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A study of “IP Over WDM” Partha Goswami 22/07/05 Topics • Motivations for IP over WDM • IP Traffic Over WDM • MPLS approch for IP over WDM • GMPLS Control Plane • Optical Internetworking and Signaling across Network Boundary 2 Motivation for IP over WDM Worldwide Network Demand •The volume of the Data traffic exceeds the Voice traffic. 30000 25000 Gb/s 20000 Data 15000 Voice 10000 5000 0 1996 1997 1998 1999 2000 2001 2002 Year Reference 14: Acute need to increase the data bandwidth •Long Haul Optical network follows SONET/SDH transmission standard with time fame of 125 μ sec. • Most of the data traffics are due to IP traffic where existing transmission technique in the Fiber backbone is not giving Optimal Multiplexing. • Several alternative are in Consideration: •IP over Fiber • PPP to replace SONET •Lightweight SONET Reference 16: Exponential Growth of Internet 3 Motivation for IP over . WDM Continued.. Inflexibility in bandwidth granularity Access ring • National Ring ADM Each traffic source must use a fixed multiple of OC1 (51.84 Mbps) rate, for example, OC-3 (155Mbps), OC12 (622Mbps), OC-48 (2.4Gbps), and OC-192 (9.9Gbps). SDH-DWDM Metro ring PBX Regional ring High overhead • SONET frame require a minimum of 3% overhead for framing, status monitoring, and management. • Other Protocol overhead, Here IP Over PPP over SDH OLT OLT PBX How present network look like. 4 Motivation for IP over WDM Continued… • Advent of wavelength division multiplexing (WDM) technology that allows multiple wavelengths on a single fiber, the "IP over fiber" issue takes on a new dimension. • End stations (traffic sources) and routers (traffic switches) have a choice of wavelengths on which to direct their traffic. • High capacity of WDM and exponential growth of IP traffic is the perfect match of the need and technology Reference 15, Ch 1, Page 2 Introduction of high capacity WDM Reference 15, Ch 2, Page 14 5 Thousand fold capacity enhancement for Submarine cable system Challenges of IP over WDM • IP over WDM domain, attempts to address issues like: • Light path selection and network routing • Support for various classes of service • Algorithms for network restorations and protection scheme • Integration with existing technology • Standardization of Signaling and protocol • The future optical component technology may allow full optical switching of IP packets. • The Optical switching can be classified as follows: • Optical Circuit switching (OCS) • Optical Burst Switching (OBS) • Optical Packet Switching (OPS) 6 Three Generation of Digital Transport Network • First Generation: T1 , E1 • Second Generation : SONET , SDH • Third Generation : Optical Transport network • Suitable for: Voice, Video, Data, QOS, BOD • Multiplexing and Switching scheme: WDM/O/O/O • Capacity: Tbps • Payload: Fixed or Variable length • Protocol support: PPP, IP, ATM, MPLS • Commercial Availability: Full feature 3rd Generation yet to arrive due to lack of mass scale commercial deployment O/O/O Reference: 1, Page 1-4 7 IP Traffic Over WDM network • IP Traffic Over WDM is the Correct Choice for Next Generation Internet backbone. • OCS technology is matured. • Network node will use Wavelength Routing Switch and IP router. • Nodes are connected by fiber to form physical topology • Any two IP router will be connected by allOptical WDM Channel called light path • The set of lightpath termed as Virtual topology. • Multihop approach WRS Wave length Routed Network λ1 λ1,λ2, λ3,λ4 λ1,λ2, λ3,λ4 λ2 λ1,λ2, λ3,λ4 λ1,λ2, λ3,λ4 λ1,λ2, λ3,λ4 λ3 λ1,λ2, λ3,λ4 λ4 8 Reconfigurable Wavelength Routing node Reference 17 IP/WDM network Model IP NCM WDM NCM • IP Routers are Network element of IP Layer • WXC, WADM are Network element of WDM Layer • Overlay model: IP layer and optical layer are managed and controlled independently • IP-NCM, WDM-NCM, UNI • Integrated IP/WDM: Functionality of both IP and WDM are integrated at each node. WRS IP NCM Over Lay Model WRS + control Integrated Model Reference 18:Ch 9, Page 347-351 9 Optical Packet switching • Header Sync Header • Guard Payload Sync Payload Guard Format of an optical Packet • Header encoded at lower speed • Payload duration is fixed • Payload Variable bit rate up to 10 Gb/s • Header and payload at the same wavelength • Guard time to take care of delay variation • Sync bit used for packet synch Demux Large gap between IP route processing and the capacity of WDM because of • • One possibility is packet switching in optical domain instead of electrical domain Mux FDL Synchronizer O/E Header Delineation O/E Payload Position Switch Control Unit Header Recovery • • • Signal Regenerator Switching Fabric Payload Delineation Header updating Electrically Store and forwarding technique • Statistical Multiplexing Hardware cost Premature state Other Possible solutions in electrical domain are – – – Fast lookup Parallelism of the forwarding Label switching Technique A Generic Optical Packet switching node structure Reference 18:Ch 9, Page 365-366 Reference 19,20 10 Optical Burst Switching Core Router Edge Router Access Network • It Combines the advantages of OCS and OPS Access Network • No buffering and Electronic Processing Access Network λ0 Control Channel • High bandwidth utilization λ1 Data Channel 1 λ2 Data Channel 2 λ0 λ1 λ2 λ1 λ2 Fiber 1 λ0 λ1 FDL λ1 FDL λ2 λ1 λ2 λ2 FDL Optical Switching Network λ0 λ1 λ2 λ0 λ1 λ2 λ0 λ1 λ2 FDL Fiber 2 Mux Demux λ0 IM λ0 Optical Burst Switching node Architecture IM Control Burst Processing Routing Table OM OM Buffer And Scheduler λ0 • Burst is aggregating a no of IP datagram destined for same egress router in the ingress router • Control burst and Data Burst • Node Architecture Reference 18:Ch 9, Page 351-355 Reference 21 11 MPLS approach in WDM network IP network MPLS Network WRS IP network MPLS Back bone for IP network IP Over MPLS Over WDM • MPLS is the backbone for IP network. • MPLS approach for OCS is Known as LOCS or MPλS • MPLS approach is suitable for OBS and OPS using LOBS and LOPS respectively • If Label of the MPLS is mapped with λ of the WDM network, then IP-MPLS frame work enables direct integration of IP and WDM Reference 22,23 12 MPLS and Optical Network • MPLS is the key components for 3rd generation Transport networks. • MPLS Architecture is defined in RFC 3031 . • Operations of Label switch router (LSR), Label assignments, and Label swapping. • What is label switching and how it is different than traditional internets ? • Correlations between MPLS label value and optical wavelength Reference 1, Chapter 9 13 Advantage of Label Switching • Speed, delay and jitter: Faster than traditional IP forwarding • Scalability: Large no IP address can be associated with few labels • Resource consumption: Less resource for control mechanism to establish Label switch Path (LSP) • Route control: More efficient route control than destination based routing • Traffic Engineering: Allows network provider to engineer the link and nodes in the network to support different kind of traffic considering different constraints. • Labels and Lambdas: Wave length can be used for Label and optical router capable of O/O/O can forward the traffic with out any processing delay Reference 1, Ch 9 14 The forwarding Equivalence Class (FEC) • What is FEC? – It associates an FEC value with destination address and a class of traffic. – The class of traffic is associated with a destination TCP/UDP port no and/or protocol ID field in the IP datagram header. • Advantages of FEC – Grouping of packet into classes – For different FEC we can set different priorities – Can be used for efficient QOS operation Reference 1, Ch 9, page 151 15 Types of MPLS nodes • Ingress LSR: – User Traffic classifies into FEC. – It generate MPLS header and assign it an initial label. – If QOS is implemented then LSR will condition the traffic • Transit LSR – Uses the MPLS header for forwarding decision – It also performs label swapping – Not concerned with IP header • Egress LSR – It removes MPLS header Reference 1, Ch 9, page 152 Ingress LSR Transit LSR Egress LSR The MPLS nodes 16 Label swapping and Traffic forwarding • LSR forwarding table map the Incoming Label and interface to an Outgoing Label and interface. • Ingress LSR analyzes the FEC field and correlate the FEC with a Label, encapsulate the datagram. • The Transit LSR process only label header based on the LSR forwarding table. Reference 1, Ch 9, Page 154 and Reference 2, Ch 5, Page 151 IP L2 • An LSR may explicitly request a Label binding for an FEC from the next hop. Destination Network Source network Label allocation and MPLS forwarding 18 MPLS Support of Virtual Private Network • MPLS can be used to support VPN customers with very simple arrangement. • It is possible by label stacking : Placing of more than one Label in the MPLS header. • • • • • This concept allows certain Label to be processed by the node while others are ignored. VPN backbone can accommodate all traffic with one set of Labels for the LSP in the back bone. The customers Labels are pushed down and are not examined in the through the MPLS tunnel. IP 33 34 Customer 1 IP 33 35 IP 32 34 IP 32 35 IP 31 IP IP Customer 2 LSR A Customer 1 31 34 LSR B IP 32 Assumptions: – Customers at the same ends of the MPLS end to end path. – Customers have the same QOS requirements and FEC parameters IP 31 35 Cust 2 LSR C IP 32 VPN IP 33 Customer 3 When the packet arrive at the end of the VPN backbone LSP then the LSR pops the Labels. 31 IP 33 Customer 3 Label Stacking in VPN Reference 1, Ch 9, page 155 19 MPLS Traffic Engineering • It deals with Performance of network. • High performance required for Customer’s QOS need. • Methodologies are Measurement of Traffic and Control of Traffic. • RFC 2702 specify the requirement of TE over MPLS. • Objective of TE are Traffic Oriented and Resource Oriented performance enhancement. • Traffic oriented performance objective are minimizing Traffic loss, minimizing delay, maximizing throughput and enforcement of SLAs. • Resource oriented performance objective deals with Communication Links, Routers and Servers. • Efficient management of the available bandwidth is the essence of TE Reference 1, Ch 9, page 156-157 20 Multi Protocol Lambda switching (MPλS) • MPλS is the framework for inter working Optical networks and MPLS. Label Mgt MPLS Control Plane • MPLS and Optical network both have control plane to Manage the user traffic. LSP Cross Connect table λ Mgt • • • MPLS Control Plane deals with Label distribution and binding an end to end LSP Optical Control Plane deals with setting up wavelength, optical coding scheme (SDH/SONET), transfer rates, Protection switching options. Reference 3 and 4 discussed about adapting the MPLS TE Control Plane for optical Cross Connect. Optical Control Plane OSP Cross Connect Table The MPLS and Optical Control Plane WDM network MPLS network MPLS network over WDM network Reference 1, Ch 9, page 158 22 Relationship of OXC and LSR operations Data Transfer Control Plane Label Switch Router (LSR) Optical Cross Connect (OXC) Label Swapping operation to transfer labeled packet from an Input port to an Output port Connect optical Channel of one Input port to an Output port Discovery,distribute and maintain relevant state information related with MPLS. Discovery,distribute and maintain relevant state information related with optical Transport network (OTN) Forwarding information Forwarding information Label is appended with Data Packet Forwarding information is implied in the data Channel. Storage of switching information Input - output relation is maintained in Next hop label forwarding entry (NHLFE) Input - output relation is maintained by Wavelength forwarding information base Reference 1, Ch 9, page 159 Sending Node Receiving Node USER USER MPLS MPLS Optical Optical MPLS and Optical network Layered model 23 MPLS and MPλS Correlation MPLS MPλS Map Label to Wavelength Key aspect Label Value Optical Wavelength Ingress Node Role of Ingress Node on the user Traffic, termed as Ingress LSR MPLS Label is correlated with appropriate wavelength, termed as LSR/OXC Core node Path Termed as Transit LSR Termed as Label switch Path (LSP) Termed as Transit PXC, used to process the wavelength to make the routing decisions. Termed as Optical switched path(OSP) User Ingress LSR/OXC Process λ Transit PXC User Map wavelength to Label Egress LSR/OXC Processing of user Traffic in the MPλS Reference 1, Ch 9, page 160 24 MPLS and Optical TE similarities • MPLS term Traffic trunk = Optical Layer Term Optical Channel trail • Attributes of Traffic for MPLS TE: – – – – – – Traffic Parameters: Indicate BW requirement of traffic trunk Adaptive attributes: Sensitivity and Possibility of re-routing of trunk Priority attribute: Priority of path selection and path placement for trunk Preemption attribute: Whether a traffic trunk can preempt an existing trunk Resilience attribute: Survivability requirement of Traffic trunk Resource class affinity attribute: Restrict route selection to specific subset of resources Reference 1, Ch 9, page 162 25 Possibilities for the MPλS Network • Following work remain in Reference 4 which needs to be done to complete the MPλS Network: • Concept of link bundling. • Distribution of OTN topology , available bandwidth, available channels and other OTN topology state using extension of IS-IS or OSPF • Exploring the possibilities of fiber termination in the same device which perform the role of OXC and IP router. • Uniform Control Plane for LSR and PXC as close interaction are needed between Control and Data plane for the interwork of Label and wavelength. • How to increase the utilization of the optical Channel trail in case traffic in the LSP mapped with Optical channel is low. Reference 1, Ch 9, page 163-165 26 IP, MPLS and Optical Control Plane • • 3rd Generation transport networks encompasses three Control plane. All the above control plane need to be coordinated to take the benefit of the followings: IP Control Plane (Routing Layer) Mapping of IP Address to MPLS Label – Route discovery of IP control Plane MPLS Control Plane (Binding Layer) • Routing protocol advertises and discover address as well as routes – Traffic Engineering capability of MPLS control plane • MPLS Label distribution protocol will bind the IP address with Label – Forwarding speed of optical data plane • MPLS Label will be mapped with wavelength • Optical node can perform PXC –based O/O/O operation • O/E/O based Label label swapping will not be needed. • Ideally same wavelength can be used on each OSP segment. Reference 1, Ch 10, page 170 Data Plane (Forwarding) Mapping of MPLS Label to wavelength Data Plane (Forwarding) Optical Control Plane (λ Mapping Layer) Data Plane (λ Mapping Layer) User Payload IP Header Label Header Inter working of three Control Plane 27 Optical Control Plane • The requirement of Optical Control Plane as specified in Reference 5 • Permanent Optical channel setup by NMS by network management protocol Control • Soft permanent optical channel by NMS using network generated signaling and routing protocol • Switched Optical Channel which can be setup by customer on demand using signaling and Routing protocol • The Optical Node consist of OXC and Optical network control plane • Between two neighboring node there is pre configured control channel which may In band or Out of band. • Switching function is done by OXC but it is based on how cross connect table is configured Reference 1, Ch 10, page 169 and Reference 6, Ch 14, page 427 Control Control Data OXC OXC Optical Network Node Optical Network Node Optical Node Model 28 Generalized MPLS use in optical network • Purpose of GMPLS development: (Reference 8) • • • 1. 2. 3. 4. To support MPLS operation in optical network with ability to use the optical technologies as » Time division ( SONET ADM) » Wavelength » Spatial switching( Incoming Fiber to out going fiber) GMPLS assume that forwarding decision based on time slot , wavelength and physical ports. GMPLS Terminology: Packet switch capable (PXC): Process traffic based on packet/cell/frame boundaries Time division Multiplex capable (TDM): Process Traffic based on a TDM boundary, such as SONET/SDH node. Lambda-switch capable (LSC): Process traffic based on the Optical wavelength Fiber switch capable (FSC): Process traffic based on the physical interface. 31 Reference 1, Ch 10, page 177 Generalized MPLS use in optical network continued… • GMPLS = Extension of MPLS to support various switching technology (RFC 3945) Packet LSP • Following switching technology is considered: • Packet switching: Forwarding capability packet based, IP Router • Layer2 switching: Forwarding data on cell or frame: Ethernet, ATM • TDM or Time slot switching: Forwarding data based on time slot: SONET,DCS, ADM • Lambda switching: Performed by OXC • Fiber switching: Performed by Fiber switch capable OXC • GMPLS control plane focus on full range of switching technology • Natural Hierarchy of Label stacking in GMPLS: Packet LSP over Layer 2 LSP over over Time slot LSP over λswitching LSP over Fiber switching LSP Reference 26, 27 Layer 2 LSP Time slot LSP λ- LSP Fiber LSP GMPLS Label stacking LSP 32 GMPLS Control Plane • Optical network is becoming the Transport network for IP traffic (IP over Optical) Routing protocol Resource discovery and dissemination CSPF path computation Wave length Assignment • IP centric optical control plane is the best choice • GMPLS control plane for Optical network contains Routing, Signaling and Restoration Management Signaling Restoration Management GMPLS Control Plane for Optical Network 33 Reference 6, Ch 14, page 428 Resource Discovery and Link-state Information Dissemination • Each Optical node need to know the Global topology and resource information, which is possible by broadcasting local resource use and neighbor connectivity information by each optical node. • It can be done the OSPF (Reference 9) and its extension ( Reference 10) • It can also be done by IS-IS (Reference 11) and its extension (Reference 12) • Here neighbor discover require inband communication which is possible for Opaque OXC with SONET termination. • For Transparent OXC neighbor discovery generally utilizes a separate protocol such as Link management protocol ( Reference 13) • Issues: Scalability problem for link addressing and Link state advertisement • Solutions: • Unnumbered links: Globally unique end node ID ( LSR ID) plus local selector ID • Link Bundling: The link attribute of multiple wavelength channel of similar characteristics can aggregated. 34 Reference 6, Ch 14, page 428-429 CSPF Path computation • CSPF = SPF + resource constraint + policy constraint : To achieve the MPLS TE objective RFC 2702 • Such path computation is NP complete and Heurestic have to be used. • The objective of path computation in optical network is to minimize the resource required for routing light paths for a given SLA. • For optical network CSPF algorithm needs to be modified for the following reason • Link Bundling and Restoration Path Computation • The Solution is Shared Risk Link Group (SRLG): Administrative group associated with some optical Resources that probably share common vulnerability to a Single Failure. • Example: Fiber in the same conduit can be assigned with one SRLG 35 Wavelength Assignment Fiber 1 • Wave length Continuity constrained for Transparent OXC λ1 λ2 λ3 • Opaque OXC and wave length Conversion λ1 λ2 λ3 Fiber 1 λ1 λ2 λ3 λ1 λ2 λ3 Fiber 2 Fiber 2 Transparent OXC • Wave Length Assignment Problem is constrained to the CSPF algorithm • Wave length assignment • At the Source • Random wave length assignment • Dynamic wavelength Reservation Reference 6, Ch14, Page 430 Reference 24,25 λ1 λ2 λ3 λ1 λ2 λ3 λ4 λ5 λ6 λ4 λ5 λ6 Fiber 1 Fiber 1 Opaque OXC 1 2 3 Light Path Demand set in a ring 36 Restoration Management • Difference between Optical Layer protection with IP layer MPLS Layer. • Management and co-ordination among multiple layer is an important issue. • Optical Protection mechanism can be classified as follows: • Path Protection • Link Protection Path Protection classified as follows: • Disjoint Path Protection: 1+1 , 1:1 and M:N • Link-dependent Path protection • • Restoration Management: Failure detection, Failure notification and Failure restoration. • Detection by lower layer impairments, higher layer link probing. • Time for restoration is due to restoration path computation and traffic rerouting from primary path to restoration path Reference 6, Ch14, Page 431 37 Signaling • Signaling is distributed path establishment operation across Optical network • Major Operation of Light Path signaling are Light Path setup, Teardown and Abort • Light Path Setup: SETUP, SETUP ACK, SETUP NAK • Light Path commitment Phase: ABORT • Light Path Teardown : TEARDOWN and TEARDOWN ACK DST SRC INT_A INT_B SETUP SETUP • Addressing Issue due to High no of entity in Optical network: Unique IP to OXC and other resources through Selector • Each node will Maintain a Light Path table to record the Lightpath ID, Incoming/ Out going Port no, SRLG so on.. SETUP SETIP ACK SETIP ACK SETIP ACK Reference 6, Ch14, Page 432-435 38 GMPLS Signaling Functional Requirements • Same switching functionality for both end LSR • GMPLS extends MPLS Signaling in many aspect • Generalized label is defined with enough flexibility to represent Label for different switching type. • Label suggestion capability by the upstream node will reduce the LSP setup delay. • Label set: Upstream restrict the label selection of the down stream to acceptable limit. • GMPLS support Bi-directional LSP setup. • Explicit Label label selection offers capability of explicit label selection on a specific on an explicit route • GMPLS data channel and control channel may be separate. • GMPLS signaling for fault handling should minimize the packet loss. Reference 6, Ch14, Page 435-436 39 IP – Centric Control Plane Receive incoming message Process the request with the help of other module Initializing the control Plane IP Network UNI Optical Network Main Module (MM) Connection Module (CM) Resource Management Module (RMM) Protection/ Restoration Module (PRM) •Light Path Signaling •Maintenance •Routing and wavelength Assignment (RWA) •Topology and Resource Discovery •QOS support Reference 6, Ch14, Page 461-469 Reference 28 •Survivability •Fault Monitoring •Fast Protection/ Restoration 42 Connection Module (CM) •Connection Request Message Contents •Light Path ID •Light Path Type (Primary/ Protection) •Routing Path •Assigned wave Length •QOS type •SRLG list of Primary Path IP Network UNI Optical Network •At each hop, request Message is processed •Destination node send ACK along the same path •If there is resource conflict NAK is sent back Light Path ID Status SRC DEST SEQ NODE NODE NUM ID ID (Creating/ Reserved/ Active/ Deleted) QOS Type Input Port ID Output Port ID λ ID 43 Connection Module (CM) Continued…… 1 Creating Processing of Lightpath signaling Resource Reservation/ Release QOS = best Effort If Assigned wavelength is available Set the wavelength status “ Used Preemptible” 5 4 2 6 Lightpath State Transfer Deleted Active 3 Determination of Input/ Output port from the LT NAK Reserved QOS= Protection Sensitive If it is Primary Path and wavelength status “ available” change the status to “ Used Preemptible” If it is Protection LightPath and wavelength status “ available” Set the status to” Reserved” Else Check the SRLG list QOS = Mission Critical If Assigned Wavelength is available Change the status to to “ Used and Non-perrmptible” Else abort the existing lightpath on this wavelength. Then Change the status to to “ Used and Non-perrmptible” 1. 2. 3. 4. 5. 6. Protection Path: Reservation Ack Failure on Primary path Tear Down abort NAK 44 Primary Path : Setup ACK Tear Down Abort Resource Management Module • • • • • IP Network Functionality: Resource Discovery, Maintenance, QOS support, RWA Neighbor discovery mechanism by sending Hello Message on all out going link. Local Connectivity Vector (LCV): Store the cost of the Adjacent Node. If LCV is updated , it is broadcasted to the network Local resource availability stored in Local Resource Table (LRT) • “λi status” indicate state of ith wavelength in the fiber attached to the port • Possible states are “used and preemptable” , “used and non-preemptable” , “Reserved”, “Available” and “ Faulty” • “λi SRLG list” stores the SRLG information of the primary path whose protection path has reserved the wavelength (λi status = Reserved) UNI Optical Network Port no Peering Node ID λ1 status λ2 status λ1 SRLG list λ2 SRLG list Local Resource Table (LRT) 45 … Resource Management Module Continued…. • Each node build its own Topology connectivity Matrix (TCM) with N nodes. Optical Network • Each row of TCM is the LCV of the node I plus a time stamp. • RMM also maintain a Global Resource Table (GRT) consisting of LRT of all nodes. • RMM utilize different RWA algorithm to support QOS. • QOS support: • Best-effort service • Mission critical service • Protection Sensitive Matrix Node 1 Node 2 Node 3 Node 4 Node 5 Node 1 Node 2 Node 3 Node 4 Node 5 Node 6 Topology Connectivity Matrix 46 Node 6 Protection and Restoration Module • • • • • • • Functions: Setup Co-ordination of Primary and protection Light Path, Fault detection, and notification. Fault can be detected by as follows: • Low level impairments • Higher layer link probing Failure can happen for Control Plane or OXC. Failure indication Signal (FIS) send to the source node. If Qos requirement is Restoration the restoration Path will be calculated. Connection Request NAK/ACK Control Plane of Node A (MM) (CM) (MM) (RMM) (PRM) Control If Qos requirement is Protection then source node will invoke the setup signal for the Lightpath previously reserved. For Mission critical destination node detect the failure of the primary Lightpath and turn to protection path. Control Plane of Node A (CM) Control (RMM) (PRM) Control Data OXC OXC Optical Network Node A Optical Network Node B 47 Optical Internetworking and Signaling across Network Boundary • Need for Inter-domain Optical network • Need for standard • Addressing scheme to identify light path end points • Routing Protocol • Standard signaling protocol across Network to Network interface • Restoration procedure • Policies that affect the flow of Control Information • • • Solution is by implementing: • External Signaling Protocol (ESP): Used for Signaling across NNI • Internal Signaling protocol( ISP): May be different for different network Possibility of BGP extension is being studied for Routing . Possibility of CR-LDP or RSVP-TE extension is being studied for Signaling across the network boundary. NNI NNI 48 Signaling across NNI Reference 6, Ch14, Page 459-461 ISP ISP ISP ISP ISP ESP ISP ESP ISP ESP ISP ESP ISP ESP ISP ESP ISP ESP ISP ESP ISP ESP ISP ESP ISP ISP ESP ISP ESP ISP ISP ISP ESP ISP ESP ISP ISP ISP ESP ISP ESP ISP ISP ISP ESP ISP ESP ISP ISP ISP ESP ISP ESP ISP ISP 49 Conclusion • Development and implementation of GMPSL over the existing technology can only bring the reality of IP over WDM • Performance of GMPLS in the hybrid scenario should be simulated. 50 References 1. 2. Optical Networks, Third Generation Transport Systems by Uyless Black Optical Network Control Architecture, Protocols, and Standards by Greg Bernstein 3. Multiprotocol Lambda Switching:Combining MPLS Traffic Engineering Control with Optical Crossconnects by Daniel Awduche, Movaz NetworksYakov Rekhter, Juniper Networks , IEEE Communications Magazine • March 2001 4. Multi-Protocol Lambda Switching: Combining MPLS Traffic Engineering Control With Optical Crossconnects draft-awduche-mpls-te-optical-03.txt 5. Considerations on the development of an Optical Control Plane, Internet Draft Document: draft-freeland-octrl-cons-01.txt by IP-Optical Working Group 6. IP Over WDM: Building the next Generation Optical Internet, Edited by Sudhir Dixit 7. IP over Optical Networks: A Framework: draft-ietf-ipo-framework-00.txt by Bala Rajagopalan 8. Generalized MPLS - Signaling Functional Description: draft-ietf-mpls-generalized-signaling05.txt by Network Working Group 9. OSPF Version 2: RFC 2328 51 Reference Continued…. 10. OSPF Extensions in Support of Generalized MPLS: draft-ietf-ccamp-ospf-gmpls-extensions-00.txt 11. Use of OSI ISIS for Routing in TCP/IP and Dual Environments: RFC 1195 12. IS-IS Extensions in Support of Generalized MPLS: draft-ietf-isis-gmpls-extensions-04.txt 13. Link Management Protocol (LMP) : draft-ietf-ccamp-lmp-10.txt 14. http://www.cs.columbia.edu/~hgs/internet/traffic.html 15. WDM Technologies, Volume III - Optical Networks - 2004 - (By A.K.Dutta) 16. http://bgp.potaroo.net/ 17. Design of Logical Topologies for Wavelength-Routed Optical Networks, Rajiv Ramaswami, IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 14, NO. 5, JUNE 1996 18. WDM Optical Networks: Concept, Design and Algorithm by C. Siva Ram Murthy 19. Transparent Optical Packet Switching: The European ACTS KEOPS Project Approach, JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 16, NO. 12, DECEMBER 1998 20. High-capacity Multi-service optical label switching for the next generation Internet, IEEE Optical Communications * May 2004 21. Choices, Features and Issues in Optical Burst Switching, Optical Network Magazine, Vol.1, no.2, pp 36-44, April 2000 52 Reference Continued…. 22. On IP-over-WDM Integration, IEEE Communications Magazine • March 2000 23. Labeled Optical Burst Switching for I P-over-W DM Integration, IEEE Communications Magazine September 2000 24. Efficient Distributed Control Protocols for WDM All-Optical Networks*Computer Communications and Networks, 1997. Proceedings 25. Lightpath Communications: An Approach to High Bandwidth Optical WDM’s by Imrich Chlamtac, IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 40, NO. 7. JULY 1992 26. Generalized Multiprotocol Label Switching: An Overview of Routing and Management Enhancements, IEEE Communications Magazine • January 2001 27. Generalized Multi-Protocol Label Switching (GMPLS) Architecture, RFC 3945 28. On an IP-Centric Optical Control Plane, IEEE Communications Magazine September 2001 53