Internet Draft Dae-Gun Kim KT and Document: draft-kim-ccamp-gmpls-mgoxc-00.txt Korea University Expiration Date: December 2003 Gyu Myoung Lee Jun Kyun Choi ICU SungChang Lee Hankuk Aviation University Jin Woo Park Chul-Hee Kang Korea University June 2003 GMPLS Extensions to support Multi-Granularity Optical Cross-Connect with Heterogeneous Optical Interfaces draft-kim-ccamp-gmpls-mgoxc-00.txt Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of [RFC2026]. The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Abstract This document defines information needed when GMPLS signaling is used on the multi-granularity of optical cross-connect (MG-OXC) over Generalized Multiprotocol Label Switching (GMPLS) networks because existing documents deal only with singular wavelength OXC. The basic optical label handlings (including add, drop, swap, merge, and stack) are required for using the MG-OXC in GMPLS networks. Also the protocol related to signaling is extended for supporting the MG-OXC. Kim et al Expires - December 2003 [Page 1] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 Conventions The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. Table of Contents 1. Introduction....................................................2 1.1. Terminology and Definitions.................................3 2. The Architecture of Multi-granularity Optical Cross-Connect.....4 2.1. MG-OXC Node Architecture....................................4 2.2. Network Hierarchy in MG-OXC Networks........................6 3. Label Handlings in MG-OXC based GMPLS networks..................7 4. Signaling extensions for MG-OXC networks........................8 4.1. MG-OXC Parameters...........................................8 4.2. RSVP-TE Details............................................10 4.3. CR-LDP Details.............................................11 5. Operation and Management Considerations........................11 6. Security Considerations........................................12 References........................................................12 Author's Addresses................................................13 1. Introduction According to the recent rapid increasing of IP traffic, Wavelength Division Multiplexing (WDM) technology is becoming a technology-of- choice to meet the tremendous bandwidth demand of IP traffic. WDM networks using wavelength routing by optical cross-connect(OXC) have emerged as the most feasible architecture solution for next generation optical networks. OXC facilitate the switching of individual wavelengths at the nodes of a WDM-based network. However, increase in the number of wavelength channels results in increased complexity of OXCs and increased difficulty in implementing and maintaining OXCs. The concept of multi-granularity OXC (MG-OXC) has been recently introduced as a means to reduce OXC complexity [WAVEBAND][HCROSS]. MG-OXC can not only switch traffic at multiple granularities such as fiber, waveband, wavelength, but also add and drop traffic at multiple granularities. Note that multi-granularity of MG-OXC means the multiple granularities of optical interfaces in MG-OXC and does not mean the granularity of bandwidth in network resources. The waveband is formed by grouping several wavelengths and is routed as a single channel. Also the fiber channel is formed by grouping several wavebands and is routed as a single channel. Kim et al Expires - December 2003 [Page 2] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 This document defines information needed when GMPLS signaling is used on the MG-OXC over Generalized Multiprotocol Label Switching (GMPLS) networks because existing documents deal only with singular wavelength OXC. The basic optical label operations (including add, drop, swap, and stack) are performed by using the MG-OXC at nodes in GMPLS networks. And new recovery mechanism for MG-OXC is provided because existing recovery approaches deal only with failures of OXCs with only individual wavelengths and fiber/link failure. The protocol related to signaling is extended for the multi-granularity optical cross-connect. A main goal of this work is to provide interoperable functionality in multi-vendor service provider networks. To maintain consistency in the provision of end-to-end service in a multi-provider environment, rules governing the operations of recovery mechanisms at domain boundaries must also be specified. 1.1. Terminology and Definitions The reader is assumed to be familiar with the GMPLS terminology as defined in [GMPLS-ARCH]. The following abbreviations are used in this document: - OXC (Optical Cross-Connect) - MG-OXC (Multi-Granularity OXC) Several wavelengths are grouped together as a waveband and switched as a single port whenever possible. A waveband is demultiplexed into individual wavelengths if and only if necessary when the waveband carries at least one lightpath that needs to be dropped or added. Multi-granularity OXCs not only switch traffic at multiple layers such as wavelength, waveband, and fiber, but also add and drop traffic at multiple granularities. - WXC (Wavelength Cross-Connect) This is to switch lightpaths by wavelength unit. - BXC (Waveband Cross-Connect) This is to switch lightpaths by waveband unit. The waveband is formed by grouping several wavelengths and is routed as a single channel. - FXC (Fiber Cross-Connect) This is to switch lightpaths by fiber unit. The fiber channel is formed by grouping several wavebands and is routed as a single channel. Note) MG-OXC is composed of WXC, BXC and FXC (see Figure 1). - Optical LSP (Label Switched Path) This include the W-LSP, B-LSP, F-LSP Kim et al Expires - December 2003 [Page 3] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 - W-LSP (Wavelength Label Switched Path) - B-LSP (Waveband Label Switched Path) - LSP (Fiber Label Switched Path) - Network Hierarchy This is an abstraction of a part of a networkÆs topology, routing and signaling mechanisms. Abstraction may be used as a mechanism to build large networks or as a technique for enforcing administrative, topological, or geographic boundaries. For example, network hierarchy might be used separate the regional and backbone sections of a network, or to interconnect service provider networks (with BGP which reduces a network to an Autonomous System). - Vertical Hierarchy This is oriented between two network technology layers. - Horizontal Hierarchy This is oriented between two areas or administrative subdivisions within the same network technology layer. 2. The Architecture of Multi-granularity Optical Cross-Connect 2.1. MG-OXC Node Architecture In GMPLS networks, an OXC consists of three major parts: demultiplexer, optical switch matrix, and multiplexer. OXC complexity can be characterized by the size of optical switch matrix. Note that intermediate traffic dominates over end-to-end traffic in GMPLS networks. Since many lightpath conveying intermediate might have the same route, the size of the optical switch matrix would be largely reduced if they were dealt with as a single channel or port. In single granularity OXCs, OXC switches traffic only at the wavelength layer and wavelengths either terminate at or transparently pass through a node, each requiring a port. However, in multi-granularity OXCs several wavelengths are grouped together as a waveband and switched as a single port whenever possible. A waveband is demultiplexed into individual wavelengths if and only if necessary when the waveband carries at least one lightpath that needs to be dropped or added. Multi-granularity OXCs not only switch traffic at multiple layers such as wavelength, waveband, and fiber, but also add and drop traffic at multiple granularities. Traffic can be transported from one layer to another via multiplexers and demultiplexers within the MG-OXC. The architecture of multilayer MG-OXC node is shown in Figure 1, which includes the wavelength cross-connect (WXC), waveband cross- connect (BXC), and fiber cross-connect (FXC) layers. As shown in Figure 1, the WXC and BXC layers consists of cross-connects and multiplexers/demultiplexers. The WXC layer includes a WXC that is used to switch lightpaths. To add/drop wavelengths from the WXC layer, we need wavelength add/drop ports. In addition, waveband to Kim et al Expires - December 2003 [Page 4] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 wavelength demultiplxers are used to demultiplex wavebands to wavelengths, and wavelength to waveband multiplexers are used to multiplex wavelengths to wavebands. At the BXC layer, the waveband cross-connect, waveband add/drop ports are used for bypass and add/drop wavebands. Fiber to waveband demultiplexers are used to demultiplex fibers to wavebands. Waveband to fiber multiplexers are used to multiplex wavebands to form fibers. Similarly, fiber cross- connect and fiber add/drop ports are used to switch and add/drop fibers at FXC layer. In order to reduce the number of ports, the MG- OXC switches a fiber using one port at the fiber cross-connect if none of its wavelength is used to add to drop a lightpath. Otherwise, it will demultiplex the fiber into wavebands, and switch an entire wavebands using one port at the waveband cross-connect if none of its wavelength is used to add to drop a lightpath. In other words, only the wavebands whose wavelengths are needed to be added or dropped will be demultiplexed, and only the wavelengths in those wavebands that carry bypass traffic needed to be switched using the WXC. With this architecture, it is possible to dynamically select fibers for multiplexing/demultilexing from the FXC to the BXC layer, and wavebands for multiplexing/demultiplexing from the BXC to the WXC layer. add/drop +---+ <-------| |--------> +----+ | | +----+ +--->|DMUX|---|WXC|----|MUX |----+ | +----+ | | +----+ | | | | | | +---+ | | | | +---+ | +-------------| |<-------------+ +----+ | | +-----+ +----|MUX |---|BXC|----|DMUX |<--+ | +----+ | | +-----+ | | <-------| |--------> | | add/drop +---+ | | | | +---+ | +------------>| |--------------+ |FXC| <--------| |--------> add/drop +---+ [FIGURE 1] The Node Architecture of of three layer Multi-Granularity Optical Cross-connect (MG-OXC) GMPLS in conjunction with MG-OXCs can be bring about tremendous benefits in terms of reducing the number of ports of OXCs, which in turn reduces the size of the OEO (optical-electrical-optical) Kim et al Expires - December 2003 [Page 5] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 grooming switch, as well as the cost and difficulty associated with controlling them. In addition to reducing the port count, the use of wavebands reduces the number of entities that have to be managed in the system, and enables hierarchical and independent management of the information relevant to fibers, wavebands and wavelengths. Moreover, relatively small-scale modular switching matrices are now sufficient to construct large-capacity optical cross-connects, making the system more scalable. Finally all of these also result in reduced complexity of controlling the switch matrix, provisioning, and providing recovery. 2.2. Network Hierarchy in MG-OXC Networks In MG-OXC networks, the network hierarchy is established by dividing wavelength layer, waveband layer, and fiber layer. Vertical hierarchical network is between each optical layer and Horizontal hierarchical network is between two areas within the same optical layer [RFC3386]. This hierarchical LSP is created by using the label-stacking and label-merging (see section3) that allow designated MG-OXCs to exchange information with one another and act as border MG-OXCs to a large area of GMPLS networks and other MG-OXCs. The aggregation of optical LSP is carried out by stacking the labels of smaller optical LSPs. The larger optical LSP traverses through the GMPLS networks. For example, optical LSP has following relations: F-LSP > B-LSP > W- LSP. At the end of the larger optical LSP, the smaller optical LSPs are separated by label destacking. In the case of functional description needed to support GMPLS-based recovery in MG-OXC networks, Protocol specific formats and mechanisms will be described in companion documents. Due to possible failures of the ports and multiplexers/demultiplexers within a MG-OXC, as well as possible failure of waveband converters, one or more wavebands in one or more fibers may be affected, but not the entire fiber or link cable. Existing protection/restoration approaches deal only with failures of individual wavelengths and fiber/link failure. Hence, new approaches and techniques to provide effective protection and restoration based on the concept of waveband are needed, as does the use of waveband conversion and/or wavelength conversion to recover from waveband layer failures. For example, in singular OXC networks one cannot merge the traffic carried by two or more wavelengths without going through OEO (Optical-Electrical-Optical) conversions. However, in MG-OXC networks a new recovery technique can merge the critical traffic carried in a waveband affected by a waveband failure with the traffic carried by and unaffected waveband, without having to go through any OEO conversions. If a waveband is failed, instead of having to reroute the failure carried by a waveband using a backup waveband along a disjoint path, one may use waveband label-merge operation, whereby Kim et al Expires - December 2003 [Page 6] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 the traffic carried by failed wavelengths in a failed waveband can be restored on the corresponding wavelengths in other active waveband; it may also be implemented by using a novel device operating under a principle similar to that of waveband conversion, which can avoid demultiplexing waveband, as required by wavelength conversion. As another example, assume that only one wavelength in a waveband is failed. To recover from such a failure using the spare wavelength in other active waveband, one may convert a failed wavelength in a failed waveband to a spare wavelength in other active waveband at a node prior to the fault, this requires both wavebands to be demultiplexed at this node. To avoid demultiplexing of the wavebands and preserve the wavelength grouping, waveband label-swap operation, which converts one waveband to other waveband and reversely, can be used to recover from the failure. A lightpath can be segmented as many area such as, wavelength, waveband, and fiber path. Each area of optical LSP can have the same or independent local recovery mechanism from other areas that the node adjacent to the failure reroutes the optical LSP around the failure. This can occur a lot faster because no failure notification across the end-to-end networks is necessary. Local recovery mechanism can be chosen according to the recovery of GMPLS [GMPLS-REC]. 3. Label Handlings in MG-OXC based GMPLS networks In MG-OXC based GMPLS networks, the MG-OXCs are connected to the label switching router(LSR) in overlay model. A label switched path (LSP) is nothing but a lightpath. The label associated with an LSP is the wavelength, waveband, or fiber of corresponding lightpath. The encoding format of these labels (such as, wavelength label, waveband label, and fiber label) is presented in [RFC3471]. The basic label handlings performed by the LSR nodes include add, drop, stack, and swap. Below, the label handlings for MG-OXC based GMPLS networks are presented. (1)label-adding and label-dropping The label-adding and label-dropping are done in a similar way as in MPLS networks. These handlings are performed at the edge of MG-OXC nodes for the terminating lightpaths. Wavelength, waveband, fiber label are performed for each lightpath (see Figure 1). (2)label-stacking The label-stack can be performed at an ingress node only when the several smaller LSPs can be aggregated to a single, larger LSP. The aggregation is carried out by stacking the labels of smaller LSPs. The larger LSP traverses through the GMPLS network. At the end of the larger LSP, the smaller LSPs are separated by label destacking. This stack operation is similar to multiplexing several virtual connections(VC) into a virtual path(VP) in ATM Kim et al Expires - December 2003 [Page 7] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 networks. The LSPs from the optical networks with singular wavelength OXC cannot be stacked, as an LSP uses the wavelength full. However, multi-granularity lightpaths are performed by optical label-stacking such that fiber label include several waveband label and waveband label is formed by several wavelength label. A lightpath can be segmented as many area such as, wavelength, waveband, and fiber path. So these smaller lightpath can be aggregated to a single, larger lightpath. (3) label-swapping At the LSR nodes traversed by an LSP, the labels are swapped. At every node the pair is mapped to . This means that label_in arriving at port_in is replaced by label_out and is sent to port_out. Since the GMPLS network is a circuit-switched network and the messages are optically switched in a lightpath, the label-swapping is performed only at a node at the time of establishing the LSP. Even then, the labels can be changed at a node only if it has wavelength or waveband conversion capability, otherwise the label remains unchanged. It is noted that label-swapping can be performed at the nodes traversed by lightpath during message transfer. 4. Signaling extensions for MG-OXC networks 4.1. MG-OXC Parameters The traffic parameters for MG-OXC are organized as follows: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Signal Type | CT | NC | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transparency (T) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Profile (P) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Signal Type (ST): 8 bits This field indicates the type of Elementary Signal that comprises the requested LSP. Several transforms can be applied successively on the Elementary Signal to build the Final Signal being actually requested for the LSP. Permitted Signal Type values for MG-OXC are: Kim et al Expires - December 2003 [Page 8] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 Value Type (MG-OXC input/output transformation) ----- ---------------------------------------- 1 wavelength/wavelength 2 wavelength/waveband 3 waveband/ wavelength 4 waveband/ waveband 5 waveband/ fiber 6 fiber/waveband 7 fiber/fiber Conversion Type (CT):8 bits This field indicates the type of Optical Conversion about the Elementary Signal that comprises the requested LSP. Permitted Conversion Type values for MG-OXC are: Value Type of Conversion ----- ------------------------ 1 wavelength/wavelength 2 waveband/ waveband The entire field is set to zero to indicate that no conversion is requested at all (default value). A non-zero field indicates that some conversion is requested. Number of Components (NC): 16 bits This field indicates the number of signals that are composed from the signal type (wavelength or waveband). Transparency (T): 32 bits This field is a vector of flags that indicates the type of transparency being requested. The default value for this field is zero, i.e. no transparency requested. Transparency, as defined from the point of view of this signaling specification, is only applicable to the fields in the Signal Types. Transparency is not applied at the interfaces with the initiating and terminating LSRs, but is only applied between intermediate LSRs. The transparency field is used to request an LSP that supports the requested transparency type; it may also be used to setup the transparency process to be applied at each intermediate LSR. Kim et al Expires - December 2003 [Page 9] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 Flag 1 (bit 1): wavelength layer Flag 2 (bit 2): waveband layer Flag 3 (bit 3): fiber layer Intermediate and egress nodes MUST verify that the node itself and the interfaces on which the LSP will be established can support the requested transparency. If the requested flags can not be supported, the receiver node MUST generate a PathErr/NOTIFICATION message. Profile (P): 32 bits This field is intended to indicate particular capabilities that must be supported for the LSP, for example monitoring capabilities. No standard profile is currently defined and this field SHOULD be set to zero when transmitted and SHOULD be ignored when received. In the future TLV based extensions may be created. 4.2. RSVP-TE Details For RSVP-TE, the MG-OXC traffic parameters are carried in the MG- OXC SENDER_TSPEC and FLOWSPEC objects (see [RFC2205]). The content of the objects is defined above in section 4.1. The objects have the following class and type: MG-OXC SENDER_TSPEC object: class = 12, C-Type = TBA (by IANA) MG-OXC FLOWSPEC object: class = 9, C-Type = TBA (by IANA) For a particular sender in a session the contents of the FLOWSPEC object received in a Resv message SHOULD be identical to the contents of the SENDER_TSPEC object received in the corresponding Path message. If the objects do not match, a ResvErr message with a "Traffic Control Error/Bad Flowspec value" error SHOULD be generated. Intermediate and egress nodes MUST verify that the node itself and the interfaces on which the LSP will be established can support the requested Signal Type, CT and NC (as defined in Section 4.1). If the requested value(s) can not be supported, the receiver node MUST generate a PathErr message with a "Traffic Control Error/ Service unsupported" indication (see [RFC2205]). Intermediate nodes MUST also verify that the node itself and the interfaces on which the LSP will be established can support the Kim et al Expires - December 2003 [Page 10] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 requested Transparency (as defined in Section 4.1). If the requested value(s) can not be supported, the receiver node MUST generate a PathErr message with a "Traffic Control Error/Service unsupported" indication (see [RFC2205]). 4.3. CR-LDP Details For CR-LDP, the MG-OXC traffic parameters are carried in the MG-OXC Traffic Parameters TLV. The content of the TLV is defined above in Section 2.1. The header of the TLV has the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The type field for the MG-OXC Traffic Parameters TLV is: TBA (by IANA). Intermediate and egress nodes MUST verify that the node itself and the interfaces on which the LSP will be established can support the requested Signal Type, CT and NC (as defined in Section 4.1). If the requested value(s) can not be supported, the receiver node MUST generate a NOTIFICATION message with a "Resource Unavailable" status code (see [RFC3212]). Intermediate nodes MUST also verify that the node itself and the interfaces on which the LSP will be established can support the requested Transparency (as defined in Section 4.1). If the requested value(s) can not be supported, the receiver node MUST generate a NOTIFICATION message with a "Resource Unavailable" status code (see [RFC3212]). 5. Operation and Management Considerations In considering the Operation and Management of the GMPLS network based on multi-granularity OXC (wavelength, waveband, fiber layer), the following requirements of each layer should be considered respectively. - information about virtual topology (set of light path connected between MG-OXCs) of each layer - information about link state of each layer - lightpath grouping strategy depending on whether the number of wavebands in a fiber is fixed or variable - information about physical topology (set of fiber connected between MG-OXCs) Kim et al Expires - December 2003 [Page 11] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 - information about the continuity of wavelength or waveband allocated to each link, e.g. wavelength or waveband converter is equipped or not - information about switching capability and port usage (information of capability of fiber, waveband, and wavelength switching for each port) - information about fiber, the physical link, for example the number of available wavelengths per waveband or fiber, directionality, optical SNR of wavelength, BER - information about the light path, for example, the identity (ID) of the component at the destination network, port ID of adding light path, port ID of dropping, directionality, Fiber ID, throughput per wavelength and waveband, end-to-end SNR, etc. 6. Security Considerations This document does not introduce new security issues beyond those inherent in GMPLS. It is, however, possible that using the suggested network management attributes provisioning can be done as administrative usage. References [WAVEBAND] X. Cao et al.,"Waveband Switching in Optical Networks," IEEE Communications Magazine, April 2003, pp105 - 112. [HCROSS] M. Lee et al.,"Design of Hierarchical Crossconnect WDM Networks Employing A Two-Stage Multiplexing Scheme of Waveband and Wavelength,ÆÆ IEEE JSAC, vol. 20, no. 1 January 2002, pp 166-71. [GMPLS-ARCH] Mannie, E.,"Generalized Multi-Protocol Label Switching Architecture", Internet Draft, Work in progress, draft- ietf-ccamp-gmpls-architecture-07.txt, May 2003. [LMP] Lang, J., "Link Management Protocol (LMP)", Internet Draft, Work in progress, draft-ietf-ccamp-lmp-09.txt, June 2003. [GMPLS-REC] Eric Mannie,D. Papadimitriou "Recovery (Protection and Restotation) Terminology for GMPLS", IETF Draft, Work in progress, draft-ietf-ccamp-gmpls-recovery- terminology-02.txt,May 2003. [RFC2026] S. Bradner, "The Internet Standards Process -- Revision 3", RFC 2026, October 1996. [RFC2119] Brander, s., " Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2205] Braden, R., et al., "Resource ReSerVation Protocol (RSVP) -- Version 1 Functional Specification", RFC 2205, September 1997. [RFC3212] Jamoussi, B., et al., "Constraint-Based LSP Setup using LDP", RFC 3212, January 2002. Kim et al Expires - December 2003 [Page 12] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 [RFC3386] W. Lai, D. McDysan,"Network Hierarchy and Multilayer Survivability," IETF RFC 3386, November 2002. [RFC3471] L. Berger (Editor),"Generalized Multi-Protocol Label Switching (GMPLS) Signaling Functional Description", IETF RFC 3471, January 2003. Author's Addresses Dae-Gun Kim KT(Korea Telecom) and Korea University 206 Jungja-dong,Bundang-gu, Sungnam-City, Kyonggi-do,463-711, Korea Phone : 82-2-929-5625 e-mail : dkim@kt.co.kr Gyu Myoung Lee Information and Communication University (ICU) 58-4, Hwaam-dong, Yuseong-gu, Daejeon, 305-732, Korea Phone: 042-866-6122 e-mail : gmlee@icu.ac.kr Jun Kyun Choi Information and Communication University (ICU) 58-4, Hwaam-dong, Yuseong-gu, Daejeon, 305-732, Korea Phone: 042-866-6122 e-mail : jkchoi@icu.ac.kr SungChang Lee Hankuk Aviation University 200-1, Hwajon-dong, Koyang-city, Kyonggi-do, 412-791,Korea Phone: 02-300-0127 e-mail: sclee@mail.hangkong.ac.kr Jin Woo Park Korea University 1,5-ka, Anam-dong, Sungbuk-ku, Seoul, 136-701, Korea Phone: 82-2-3290-3225 e-mail: jwpark@korea.ac.kr Chul-Hee Kang Korea University 1,5-ka, Anam-dong, Sungbuk-ku, Seoul, 136-701, Korea Phone: 82-2-927-6116 e-mail: chkang@widecomm.korea.ac.kr Kim et al Expires - December 2003 [Page 13] draft-kim-ccamp-gmpls-mgoxc-00.txt June 2003 Full Copyright Statement "Copyright (C) The Internet Society 2003. All Rights Reserved". This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into Document: draft-kim-gmpls-mgoxc-00.txt Expiration Date: December 2003 Kim et al Expires - December 2003 [Page 14]