(12) United States Patent
`(10) Patent No.:
`US 7,664,123 B2
`
`Ashwood Smith et a].
`(45) Date of Patent:
`Feb. 16, 2010
`
`USOO7664123B2
`
`(54) GENERALIZED VIRTUAL ROUTER
`
`(75)
`
`Inventors: Peter Ashwood Smith, Hull (CA);
`Hamid Ould-Brahim, Kanata (CA);
`Bilel Jamoussi, Nashua, NH (US);
`Donald Fedyk, Grown: MA (Us)
`_
`_
`.
`(73) ASSlgneei Norm Networks lelteds St Laurent:
`b
`CA
`Que eC (
`)
`Subject to any disclaimer, the term of this
`patent 15 extended or adjusted under 35
`
`( * ) Notice:
`
`(5 6)
`
`(58) Field of Classification Search ....................... None
`See application file for complete search history.
`.
`References C‘ted
`US. PATENT DOCUMENTS
`2003/0147402 A1 *
`8/2003 Brahim .................. 370/395.53
`2004/0255028 A1 * 12/2004 Chu et al.
`................... 709/227
`2006/0251419 A1 * 11/2006 Zadikian et al.
`............... 398/51
`* cited by examiner
`Primary ExamineriDuc C Ho
`(74) Attorney, Agent, or FirmiAnderson Gorecki &
`
`(22)
`
`(65)
`
`Filed:
`
`Jan. 22: 2004
`_
`_
`_
`Prlor Publicatlon Data
`US 2005/0163101 A1
`Jul. 28, 2005
`
`(51)
`
`Int. Cl,
`(2006.01)
`H04L 12/28
`(52) US. Cl.
`....................................... 370/401; 370/392
`
`A generalized Virtual router is disclosed. A routing and
`switching apparatus includes a switching fabric and a matrix
`of switching and routing elements. At least some of the ele-
`ments are interconnected by the switching fabric. A router
`control provides control for the switching fabric. The appa-
`ratus has both cross-connect and routing functionality.
`
`7 Claims, 10 Drawing Sheets
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`144
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`Petitioner Huawei - Exhibit 1001, p. 1
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`Petitioner Huawei - Exhibit 1001, p. 1
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`Petitioner Huawei - Exhibit 1001, p. 2
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`Petitioner Huawei - Exhibit 1001, p. 2
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`Feb.16,2010
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`Petitioner Huawei - Exhibit 1001, p. 3
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`Petitioner Huawei - Exhibit 1001, p. 3
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`Petitioner Huawei - Exhibit 1001, p. 4
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`Petitioner Huawei - Exhibit 1001, p. 4
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`Petitioner Huawei - Exhibit 1001, p. 5
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`Petitioner Huawei - Exhibit 1001, p. 5
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`Petitioner Huawei - Exhibit 1001, p. 6
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`US. Patent
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`Feb. 16, 2010
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`Petitioner Huawei - Exhibit 1001, p. 7
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`Petitioner Huawei - Exhibit 1001, p. 7
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`Petitioner Huawei - Exhibit 1001, p. 8
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`U.S. Patent
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`U.S. Patent
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`Petitioner Huawei - Exhibit 1001, p. 10
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`Petitioner Huawei - Exhibit 1001, p. 10
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`US. Patent
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`Feb. 16, 2010
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`Sheet 10 of 10
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`US 7,664,123 B2
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`FIGURE10
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`Petitioner Huawei - Exhibit 1001, p. 11
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`Petitioner Huawei - Exhibit 1001, p. 11
`
`

`

`1
`GENERALIZED VIRTUAL ROUTER
`
`FIELD OF THE INVENTION
`
`This invention relates to Virtual routers (VRs) and, in par-
`ticular, a generalized Virtual router (GVR) that is an IP-based
`layer-3 VR combined with the functionality of a Virtual pri-
`vate packet/TDM/wavelength/fiber GMPLS-based cross-
`connect.
`
`BACKGROUND OF THE INVENTION
`
`While the use of multi-protocol label switching (MPLS) in
`core networks is well known, providing generalized multi-
`protocol label switching (GMPLS) within core networks is
`currently being explored.
`GMPLS can be understood as follows. First, a label edge
`router (LER), a label switch path (LSP) and a label switch-
`router (LSR) are components within an MPLS network.
`LERs are routers on the edge ofthe network that attach labels
`to packets based on a forwarding equivalence class (FEC). An
`LSP is essentially the predetermined route that a set of pack-
`ets bound to an FEC traverse through an MPLS network to
`reach their destination. Each LSP is unidirectional. An LSR is
`
`a router capable of forwarding packets according to a label
`switching algorithm. As opposed to LERs which can be found
`On the edge of the network, LSRs are found in the core of the
`network.
`
`incoming packets to an
`In terms of overall operation,
`MPLS network are assigned a label by an LER. Packets are
`forwarded along an LSP where each LSR makes forwarding
`decisions based solely on the contents of the label. At each
`hop, the LSR strips off the existing label and applies a new
`label which tells the next hop how to forward the packet.
`GMPLS extends MPLS from supporting packet switching
`(PSC) interfaces and switching to include support of the
`following three classes of interfaces and switching: time-
`division multiplex (TDM), lambda switch (LSC) and fiber-
`switch (FSC).
`A core network is a backbone network that provides any-
`to-any connections among devices on the network. Core net-
`works are typically a combination of switching offices and a
`transmission plant connecting switching offices together.
`Many core networks include multiple ATM switches config-
`ured in a multi-linked mesh topology. Other core networks
`include IP routers. Yet another type of core network includes
`Synchronous Optical Network (SONET)/Synchronous Digi-
`tal Hierarchy (SDH) Optical-Electrical-Opticals (OEOs)
`with routers at the edge. Providers associated with any of
`these types of core networks typically offer a limited range of
`services to customers.
`
`United States Patent Application Publication 2003/
`0147402 A1 discloses a provider network offering multi-
`service virtual private cross-connect (VPxC). The VPxC can
`appear to a customer network as a virtual node within the
`network and may be addressed using a client addressing
`scheme. A VPxC can also use techniques associated with a
`virtual private optical cross-connect (VPOxC), with the
`exception that the VPxC m ay a Iso accommodate packet-
`based links, such as IP, ATM, Ethernet or other packet-based
`links (a VPxC is a Generalized Virtual Private Cross-Con-
`nect). In a Provider Provisioned Virtual Private Service Net-
`work, a VPxC may provide packet-based layer-2, layer-3 and
`GMPLS-based Optical/TDM virtual private network (VPN)
`services where the concept of GMPLS-based Virtual Private
`optical/TDM cross-connect may be extended to include
`packet-based VPNs. The VPxC may also use technology
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`developed in provider provisioned virtual private networks
`(e.g., layer-3, layer-2, OVPNs) such as VPN auto-discovery
`used for VPOxC and generalized VPN (GVPN) as applied to
`layer-2 circuits, for example. A provider network offering
`VPxC services can include devices such as optical cross-
`connects, routers, ATM, Frame Relay or Ethernet switches,
`SONET/SDH cross-connects and other similar devices.
`
`A VR has different functionality than a VPxC. A VR is an
`emulation of a physical router at the software and hardware
`levels. Furthermore, a VR has the same mechanisms as physi-
`cal routers, and can therefore be used to provide layer-3 VPN
`services. Each VR can run any routing protocols (OSPF, RIP,
`BGP-4). VR-based mechanisms include VR using Border
`Gateway Protocol (BGP) (see Hamid Ould-Brahim et al.
`“Network based IP VPN Architecture using Virtual Routers,”
`July 2002, available at the Internet Engineering Task Force
`web site) orVPNs based on RFC 2547bis (often referred to as
`BGP/MLPS-based VPNs) (see Eric Rosen et al., “BGP/
`MPLS VPNs” available at the Internet Engineering Task
`Force web site). AVR and 2547 are only capable of IP. 2547
`cannot support either MPLS or GMPLS over its networks. A
`VR does not implement in general aVPxC type switching and
`control plane.
`It would be desirable to provide a GVR which combines
`the functionality of a VR and a VPxC.
`It would also be desirable to provide a GVR that can be
`used to provide layer-3 services, as well as layer-1 services
`such as optical/TDM VPNs.
`The GVR should be able to run routing protocols such as
`OSPF, RIP and BGP-4, and the GVR should support GMPLS.
`When instantiated on a network-level, a GVR should be
`able to implement a VPN auto-discovery mechanism. Instan-
`tiation of the GVR on a single or multiple physical network
`nodes should be possible.
`It would be desirable if the GVR could be logically/physi-
`cally interconnected to build virtual private, routed switched
`networks.
`
`Possible interfaces for the GVR should include both packet
`and optical/TDM interfaces, and the interfaces should be
`GMPLS-based, thus inheriting all GMPLS link constructs
`such as link bundling, unnumbered and numbered, to name a
`few
`
`The GVR should be a building block for a carrier wishing
`to sell a complete virtual network.
`In view of the foregoing, it would be desirable to provide a
`generalized virtual router which overcomes the above-de-
`scribed inadequacies and shortcomings.
`
`SUMMARY OF THE INVENTION
`
`invention is to provide an
`An object of the present
`improved virtual router that combines layer-3, layer-2 and
`layer-1 routing and switching functionalities.
`According to a first aspect of the present invention, there is
`disclosed a routing and switching apparatus that includes a
`switching fabric and a matrix of switching and routing ele-
`ments. At least some ofthe elements are interconnected by the
`switching fabric. A router control provides control for the
`switching fabric. The apparatus has both cross-connect and
`routing functionality.
`According to one embodiment, the apparatus can support
`GMPLS and it can also provide layer-3 VPN services.
`According to another aspect of the invention, there is dis-
`closed a fabric card for use in a routing and switching appa-
`ratus. The fabric card includes a circuit board, a switching
`fabric, and a matrix of switching and routing elements
`
`Petitioner Huawei - Exhibit 1001, p. 12
`
`Petitioner Huawei - Exhibit 1001, p. 12
`
`

`

`US 7,664,123 B2
`
`3
`attached to the circuit board. At least some ofthe elements are
`
`interconnected by the switching fabric.
`In a related embodiment,
`a CLOS architecture is
`employed, and the fabric card further includes a fabric control
`processor attached to the circuit board.
`According to yet another aspect of the invention, there is
`disclosed a method for operating a router including the steps
`of:
`
`(1) using a primary router to direct an electrical signal to a
`Virtual router that runs GMPLS; and
`(2) using the Virtual router to perform Virtual router func-
`tions.
`
`In a related embodiment, the Virtual router supports a com-
`bination of at least two of layer-2 switching Ethernet, layer-2
`switching MPLS, and layer-3 forwarding Via a network pro-
`cessor.
`
`Further features and adVantages will become apparent
`from the following detailed description taken in conjunction
`with the accompanying drawings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a schematic diagram of a SONET/SDH switch in
`accordance with the prior art.
`FIG. 2 is a schematic diagram of SONET/SDH switches
`used in combination with routers in accordance with the prior
`art.
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`FIG. 3 is a schematic diagram of generalized label-
`switched routers (GLSRs) in accordance with an embodiment
`of the inVention.
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`FIG. 4 is a perspectiVe View of cards used in a GLSR
`architecture in accordance with an embodiment of the inVen-
`tion.
`
`FIG. 5 is a diagram of a GLSR in accordance with an
`embodiment of the inVention.
`
`35
`
`FIG. 6 is a diagram of the GLSR of FIG. 5 depicting direct
`switching under top -leVel GMPLS router control according to
`an embodiment of the inVention.
`
`FIG. 7 is a diagram of the GLSR of FIG. 5 depicting signal
`direction to and from a GVR according to an embodiment of
`the inVention.
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`FIG. 8 is a diagram of the GLSR of FIG. 5 depicting a
`combination of direct switching and signal direction accord-
`ing an embodiment of the inVention.
`FIG. 9 is a diagram of a GLSR network depicting Virtual
`ring functionality according to an embodiment of the inVen-
`tion.
`
`FIG. 10 is a diagram of a network within which an embodi-
`ment of the inVention can be used.
`
`DETAILED DESCRIPTION
`
`FIG. 1 illustrates a SONET/SDH switch 10. The switch 10
`
`includes a matrix of smaller switching elements 14. An
`example of the switch 10 would be an optical cross-connect
`switch haVing a CLOS architecture (named after an inVentor
`named Charles Clos).
`The concept of an N><N cross-connect is understood by
`those skilled in the art. It is a switch fabric that can switch a
`
`signal from any N transmission lines to another N transmis-
`sion lines. Cross-connects include multiple input and/or out-
`put ports.
`Many types of optical switches are known to those skilled
`in the art. An OEO switch is a type of optical switch. An OEO
`switch changes an optical signal into electrical and performs
`switching before changing the signal back to optical. An
`important feature of OEO switches for TDM serVices is the
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`ability to extract lower-speed circuits from Optical Channel
`(OC)-48/ 192 channels and electronically switch them from
`any port to any port.
`ConVersion of light into electrical signals is important in
`the context of the Internet. To transmit an optical signal to the
`right destination location, the router must know what the
`correct destination is. To determine the right destination the
`router must read the information. To do this, the router must
`conVert the optical data to an electrical data packet for packet
`analysis.
`A synchronous transport signal-48 (STS-48 is an example
`of a signal that could be sent through the switch 10. This type
`of signal is an electrical signal. The number 48 refers to the
`bit-rate of the signal and, more specifically, the bit-rate of the
`signal would be 48x51.84 Mbits/s. Different signals can be
`sent along different paths through the matrix because path-
`ways 30 create many different paths through the matrix.
`The switch 10 allows multiple connections at one time.
`Perhaps 40 STS-48 signals might be sent through the switch
`10 at one instance in time. The switch 10 has multiple external
`ports including external ports 18 and external ports 22. Also
`there are additional ports 26 within the matrix ofthe elements
`14. Signals traVelling through the switch 10 can enter through
`the external ports 18, traVel along the pathways 30 through
`four different switching elements 14, and finally leaVe
`through the external ports 22.
`It is typical to find a midplane architecture for intercon-
`necting circuit boards in modern routers. In this midplane
`architecture, a set of port circuit boards connects to a set of
`switching circuit boards through a midplane. The midplane is
`itself a circuit board with two main surfaces. The port circuit
`boards are mounted to one main surface ofthe midplane while
`the switching circuit boards are mounted to the other surface
`of the midplane. The midplane establishes electrical path-
`ways between the main surfaces such that data signals from
`the port circuit boards can traVel to the switching circuit
`boards. Where STS signals are inVolVed, the switching layer
`can permit the distribution of STSs to network processing
`layers and back out.
`FIG. 2 shows the switches 10 being connected to routers 34
`in a known arrangement. The routers 34 direct signals to the
`switches 10 Via paths 38. Signals can also pass between the
`switches 10 as indicated by paths 42. Signals along the paths
`38 and the paths 42 are electrical.
`The arrangement ofrouters and switches illustrated in FIG.
`2 results in a large number of independent router networks
`and, therefore, a large number of Virtual routers. Each Virtual
`router has high connectiVity and, in terms ofbandwidth use, is
`operating inefficiently.
`A GLSR is a hybrid deVice that can instantiate Virtual
`routers and interconnect them to and from any input port,
`timeslot or fiber. In this manner, a GLSR network can create
`a Virtual subnetwork of Virtual routers.
`Interconnected GLSRs 100 are illustrated in FIG. 3. The
`
`GLSRs 100 introduce routing into a switching fabric at Vari-
`ous points. Referring to FIG. 1, switching elements 14 haVe
`been replaced at Various locations 104 with routing elements.
`This change reduces switching capacity, but it adds routing
`Via midplane to the optical switch architecture. The routing
`can be bypassed. Columns in the matrix of switching and
`routing elements which haVe routing elements are not exclu-
`siVely composed of routing element. A row of network pro-
`cessors can be added to the router 100. Each network proces-
`sor can route on inputs or pass-through.
`Cards which can be used to implement a GLSR architec-
`ture are shown in FIG. 4. Fabric cards 116 haVe a CLOS
`
`architecture and include a network processor mesh. Some
`
`Petitioner Huawei - Exhibit 1001, p. 13
`
`Petitioner Huawei - Exhibit 1001, p. 13
`
`

`

`US 7,664,123 B2
`
`5
`elements in the matrix of the cards 116 are routing elements
`120. Other elements in the matrix are switching elements 122.
`Depending on what is desired, the manufacturer of these
`cards could make them with mostly switching elements,
`mostly routing elements, or a variable mix.
`The fabric cards 116 also have fabric control processors
`126 in a given embodiment. Known control processors for
`switch fabric cards include functionality to configure the
`card, monitor switch state, control switch fabric switchover
`and control switch resources. The processors 126 program a
`variable number of connections (i.e. bandwidth control). The
`processors 126 also program the network processors.
`Working in conjunction with the fabric cards 116 is an
`input/output (I/O) card 130. The card 130 includes a packet
`handler interface (PHI), switches, and a network processor. In
`a wireless embodiment one or more digital signal processors
`(DSPs) would be used instead of a network processor. I/O
`card processor 132 includes a PHI and smaller switch ele-
`ments.
`
`Control processor cards 140 are for redundancy and load
`sharing. Each of the cards 140 have multiple processors 144.
`The internal operation of a particular GLSR is illustrated in
`FIG. 5. Router 148 runs GMPLS and controls a main switch-
`
`ing fabric 152. The switching fabric 152 can connect inputs to
`outputs as per normal SONET. Alternatively, the switching
`fabric 152 can terminate or originate signals at GVRs.
`Switching fabrics 160 and the switching fabric 152 are shown
`in the diagram. Physically speaking though, there are not
`multiple switching fabrics. Switching fabric 152 and switch-
`ing fabrics 160 are subsets of the switching fabric of the
`GLSR 100. Switching fabric is a term known to those skilled
`in the art as a means for permitting a signal from any input
`port to be coupled to any output port.
`Smaller routers (GVRs) 158 also run G MPLS and control
`the switching fabrics 160. The GVRs 158 have routing paths
`159. Furthermore, the GVRs 158 are embedded in the GLSR
`100.
`Each of the GVRs 158 is a combination of a VR and a
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`VPxC. A GVR is an IP-based layer-3 VR combined with the
`functionality of a virtual private packet/TDM/wavelength/
`fiber GMPLS-based cross-connect. Connection to and from
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`the GVR is through IP and/or optical/TDM routing/switching
`capable logical ports. Signals within the GVR can be routed
`and layer-3 forwarded, or they can be layer-1 switched. It will
`be appreciated by one skilled in the art that where reference is
`made to layer-1 in this detailed description, layer-0 (i.e. opti-
`cal layer) may be a substitute or addition to layer-1 where
`appropriate.
`A GVR is to be distinguished from a generalized virtual
`switch (GVS). A GVR combines the functionality of a VR
`and a VPxC, while a GVS combines a virtual layer-2 switch
`and a VPxC. More specifically, a GVS is a frame/cell layer-2
`virtual switch (FR, ATM, Ethernet, high-level data link con-
`trol, etc.) combined with the functionality of a virtual private
`packet/TDM/wavelength/fiber GMPLS-based cross-con-
`nect. Connection to and from the GVS is through layer-2
`and/or optical/TDM routing/switching capable logical ports.
`Signals within the GVS can be layer-2 switched (routed), or
`they can be layer-1 switched.
`GVR and GVS functionality can be combined to provide a
`layer-3, layer-2 and layer-1 virtual node. The combination is
`called a generalized virtual node (GVN). All concepts and
`mechanisms defined for GVR and GVS are applicable to
`GVNs, and a GVN may use one instance ofVPxC (one VPxC
`can support both GVS and GVR). Connection to and from the
`GVN is through one or more ofthe following routing/switch-
`ing capable interfaces:
`layer-3,
`layer-2,
`layer-1. Signals
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`within the GVN can be layer-2 switched (routed), routed and
`layer-3 forwarded, or they can be layer-1 switched.
`Direct switching from input to output within the router I 00
`is illustrated in FIG. 6. OC-Ns 164 carry optical signals.
`OC-N is the optical equivalent of the electrical transport
`provided by STS. The OC standards are incremental
`increases in data rates relative to OC-l at 51.84 Mbits/sec.
`The current
`levels of OC-l, OC-3, OC-12, OC-48 and
`OC-192 are specifically at 51.84 Mbits/sec, 155.52 Mbits/
`sec, 622.08 Mbits/sec, 2.48832 Gbits/sec, and 9.95328 Gbits/
`sec (or 10 Gbits/sec for simplicity). Prior to OC, data had been
`transmitted through fiber optical cable using TDM which
`sends signals representing data divided by slices of time. For
`TDM, a single optical fiber could carry only one data signal at
`a time.
`
`Thus there is optical transport outside of the GLSR 100,
`and there is electrical transport inside the GLSR 100. In this
`respect, the similarity between the GLSR 100 and known
`OEO switches is clear.
`
`transport, STS-Ms 166 are
`to electrical
`With respect
`manipulated within the GLSR 100. The router 148 in this
`diagram provides top level GMPLS router control to directly
`switch the STS-M 166 from the input to the output.
`In FIG. 7, the router 148 directs the STS-M 166 to the
`router 158. The router 158 can do layer-2 switching Ethernet,
`layer-2 switching MPLS, or layer-3 forwarding via a network
`processor. As illustrated, the STS-M 166 can be directed both
`to and from the router 158.
`
`FIG. 8 is a diagram depicting a combination of direct
`switching and signal directing. The router 158 directly cross-
`connects a subset of the STS-M 166 using GMPLS. Another
`subset of the STS-M 166 is directed to and from the router
`
`158 . Again, with respect to the latter sub set, the router 158 can
`do layer-2 switching Ethernet, layer-2 switching MPLS, or
`layer-3 forwarding via a network processor.
`The GLSR 100 can vary the amount or ratio of switching
`and routing capacity. One or more of the GVRs 158 can be
`added or removed. Referring to FIG. 5, one or more of the
`switching fabrics 160 can be added or removed.
`The GLSR 100 can implement switching or routing proto-
`cols as a virtual network. For example, the router 100 can
`implement ATM or Private Network-to-Network Interface
`(PNNI) totally isolated from all other protocols.
`A GLSR can instantiate GVRs and interconnect them.
`
`Therefore, a network of GLSR type elements can implement
`an arbitrary network of GVRs.
`A GLSR network can increase or decrease the bandwidth
`
`on any segment of any GVR network. More STS signals can
`be made available to the network’s GMPLS label bases while
`
`in mid-progress (i.e. a make-before-break mechanism adjusts
`links between GVRs).
`A GLSR network can also instantiate a switched Ethernet
`
`where the top level tree segments are created by GMPLS.
`Segment sizes can vary. Intermediate switching points can be
`instantiated (not just at the edge).
`FIG. 9 shows how a GLSR network can instantiate virtual
`
`rings. The rings can be any of the GMPLS transport types.
`Each of the line segments forming the rings represents an
`individual LSP. These LSPs can be grown, shrunk, or moved
`as necessary. Make-before-break mechanisms can be used to
`minimize loss during ring contraction or expansion. In a
`make-before-break mechanism, a second path is established
`for a given connection while an earlier established path con-
`tinues to carry data for the given connection. If the second
`path is successfully established,
`the given connection is
`switched from the first path to the second path. The first path
`is then destroyed leaving only the second path.
`
`Petitioner Huawei - Exhibit 1001, p. 14
`
`Petitioner Huawei - Exhibit 1001, p. 14
`
`

`

`US 7,664,123 B2
`
`7
`The diagram illustrates two rings. The first ring is formed
`by the line segments 176, 178, 180, 182 and 184. The second
`ring is formed by the line segments 186, 188 and 190. This
`two ring topology is referred to as a dual-ring topology.
`When transport is SONET/SDH, the behaviour of the
`GLSR network is similar to a resilient packet ring (RPR).
`RPR is a fiber-optic packet network that provides protection
`against faults. RPR implements a dual-ring topology in which
`one cable waits in standby mode to handle traffic in the event
`of a fault.
`
`The RPR behaviour similarity can be understood by the
`following example. An OC-N on path 191 enters the GLSR
`network at port 192 of GLSR 193. The corresponding exit
`from the network of the OC-N onto path 194 is through port
`195 of GLSR 196. Between the ports 192 and 195 i.e. within
`the GLSR network it is entirely electrical transport. One
`means for STS—M signals at the router 193 to get to the router
`196 is along the ring formed by the line segments 176, 178,
`180,182 and 184. Using this ring, the STS-M signals could go
`from the GLSR 193 to GLSR 197, then to GLSR b, and finally
`to the GLSR 196. Alternatively, the STS-M signals could go
`from the GLSR 193 to GLSR 199, and then to the GLSR 196.
`Traffic engineering mechanisms known to those skilled in the
`art apply in this situation.
`If however there is a failure in the ring, the STS—M signals
`can also get from the router 193 to the router 196 along the
`ring formed by the line segments 186, 188 and 190. First the
`GLSR 193 directly switches the STS-M signals from the port
`192 to port 200 under top level GMPLS router control. The
`STS-M signals could then go to the GLSR b. Alternatively,
`the STS-M signals could go from the GLSR 193 to GLSR
`199, and then to the GLSR 196.
`
`It will be appreciated by one skilled in the art that the
`functionality associated with a bi-directional network ring
`topology can be realized for the above-described ring despite
`each LSP being unidirectional. Bi-directional network ring
`topologies provide
`efficient bandwidth utilization by
`enabling data to be transferred between any pair of nodes in
`either direction a round the ring, while maintaining fast pro-
`tection against faults. The two opposing trafiic directions in a
`bi-directional ring topology are commonly referred to as an
`inner ring and an outer ring.
`A network incorporating a GVR 202 is illustrated in FIG.
`10. The GVR 202 is capable of implementing a VPN auto-
`discovery mechanism. The GVR 202 could alternatively be a
`GVS or a GVN. Client edge devices 204 are directly con-
`nected to ports of the GVR 202. Other client devices 206 are
`not directly connected to any ports of the GVR 202. First
`location VPN 208 includes the client devices 204 and 206 on
`one side of the GVR 202. Second location VPN 209 includes
`the client devices 204 and 206 on another side of the GVR
`
`202. The devices 204 and 206 can each have unique addresses
`within the network. The GVR 202 may, however, have several
`addresses associated with each of the inputs and outputs 210.
`The first three decimals of the addresses for all of these
`devices could be same.
`
`A GVR may include multiple provider-edge devices. In
`this scenario, the particular GVR could be instantiated in one
`node, and one ofthe multiple provider-edge devices would be
`directly connected to one or more client edge devices through
`a GMPLS interface. One or more VPNs would be connected
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`8
`to a provider network by these client edge and provider edge
`devices. Different types ofVPNs, such as layer-2 and layer-3,
`can be built using GVRs.
`A provider having a network of GLSRs can use GMPLS
`protocol at two levels. The first level can be used to instantiate
`pipes between the GVRs. The second level can be used
`between the GVRs to instantiate connections. Theoretically
`this recursion could continue indefinitely, but practically
`three levels are more than needed. It may be of assistance in
`understanding a GVR to categorize it as a virtual GLSR.
`A provider can use a network of GVRs to provide VPN
`services to a customer having geographically spaced apart
`network locations. Each location would interface with the
`
`network of GVRs through at least one client edge device. A
`particular client edge device could interface with one or mul-
`tiple GVRs.
`In one embodiment ofthe invention, the GVR is capable of
`running routing protocols such as OSPF, RIP and BGP-4.
`Interfaces for the described GVR can be GMPLS based
`interfaces. Therefore the GVR inherits all GMPLS link con-
`
`structs such as link bundling, unnumbered, numbered, etc.
`When instantiated on a network-level, a GVR can imple-
`ment a VPN auto-discovery mechanism. Instantiation of a
`GVR on a single or multiple physical network nodes is pos-
`sible in a preferred embodiment of the invention.
`A GVR network set up can give a customer a complete
`routed network.
`
`Glossary ofAcronyms Used
`
`FECiforwarding equivalence class
`GLSRigeneralized label switch router
`GMPLsigeneralized multi-protocol label switching
`GVNigeneralized virtual node
`GVRigeneralized virtual router
`GVsigeneralized virtual switch
`I/Oiinput/output
`LERilabel edge router
`LSPilabel switch path
`LSRilabel switch router
`MPLsimulti-protocol label switching
`0C40ptical channel
`OEogoptical-electrical-optical
`PHIipacket handler interface
`SDHisynchronous Digital Hierarchy
`SONET7Synchronous Optical Network
`STsisynchronous transport signal
`TDMitime-division multiplex
`VPOxCivirtual private optical cross-connect
`VPNivirtual private network
`VPxCivirtual private cross-connect
`VRivirtual router
`
`While the invention has been described in conjunction with
`specific embodiments thereof, it is evident that many altema-
`tives, modifications, and variations will be apparent to those
`skilled in the art in light ofthe foregoing description. Accord-
`ingly, it is intended to embrace all such alternatives.
`
`What is claimed is:
`
`1. A routing and switching apparatus comprising:
`a switching fabric;
`a matrix of switching elements and routing elements
`arranged in a CLOS architecture, at least one of said
`switching elements being connected to at least one of
`said routing elements by said switching fabric; and
`router control providing control for said switching fabric,
`
`Petitioner Huawei - Exhibit 1001, p. 15
`
`Petitioner Huawei - Exhibit 1001, p. 15
`
`

`

`US 7,664,123 B2
`
`9
`wherein said apparatus has both cross-connect functional-
`ity and routing functionality.
`2. The apparatus as claimed in claim 1 wherein said appa-
`ratus can support generalized multi-protocol label switching.
`3. The apparatus as claimed in claim 2 wherein said appa-
`ratus can provide layer-3 Virtual private network serVices.
`4. The apparatus as claimed in claim 3 wherein said appa-
`ratus can exist both physically and Virtually within a particu-
`lar network.
`
`10
`5. The apparatus as claimed in claim 3 further comprising
`a router capable of forwarding packets according to a label
`switching algorithm.
`6. The apparatus as claimed in claim 1 wherein said appa-
`ratus further comprises an intemet-protocol-based layer-3
`Virtual router.
`
`7. The apparatus as claimed in claim 2 wherein said appa-
`ratus can perform layer-3 forwarding Via a network processor.
`*
`*
`*
`*
`*
`
`Petitioner Huawei - Exhibit 1001, p. 16
`
`Petitioner Huawei - Exhibit 1001, p. 16
`
`

`

`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`CERTIFICATE OF CORRECTION
`
`PATENT NO.
`APPLICATION NO.
`
`: 7,664,123 B2
`: 10/763015
`
`DATED
`INVENTOR(S)
`
`: February 16, 2010
`: Ashwood Smith et a1.
`
`Page 1 of1
`
`It is certified that error appears in the above-identified patent and that said Letters Patent is hereby corrected as shown below:
`
`On the Title Page:
`
`The first or sole Notice should read --
`
`Subject to any disclaimer, the term ofthis patent is extended or adjusted under 35 U.S.C. 15 4(b)
`by 1732 days.
`
`Signed and Sealed this
`
`Thirtieth Day of November, 2010
`
`David J. Kappos
`Director ofthe United States Patent and Trademark Ojfice
`
`Petitioner Huawei - Exhibit 1001, p. 17
`
`Petitioner Huawei - Exhibit 1001, p. 17
`
`