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1974_chp10ONLa.fm Page 735 Tuesday, November 14, 2006 10:07 AM 1974_chp10ONLa.fm Page 736 Tuesday, November 14, 2006 10:07 AM CHAPTER SUPPLEMENT 10 Any Transport over MPLS This online supplement of Chapter 10 focuses on more advanced topics regarding Any Transport over MPLS (AToM) What if the attachment circuits (AC) on the two sides of the MPLS network have different encapsulation types? How you interconnect multiple MPLS networks that are running the AToM service and provide a Layer transport service end to end? How you switch two pseudowire segments? To conclude, this chapter looks at what local switching entails on the provider edge (PE) routers of the MPLS network L2VPN Interworking Up to this point in the book, the ACs on both sides have been the same encapsulation type, which is also referred to as like-to-like functionality L2VPN interworking is an AToM feature that allows different encapsulation types at both sides of the AToM network The interworking feature then “translates” one Layer encapsulation to another The L2VPN interworking has two possible modes: IP and Ethernet If the PE is configured for IP mode, you extract the IP packet from the received frame on the AC and label it before sending it into the MPLS network, effectively using AToM to transport pure (nonrouted) IP payload across the MPLS backbone If the PE is configured for Ethernet mode, you extract the Ethernet frame from the received frame on the AC (all VLAN headers are removed) and label it before sending it into the MPLS network Table 10-1 lists the L2VPN interworking possibilities for both the IP and Ethernet modes in Cisco IOS Table 10-1 L2VPN Interworking Possibilities Interworking Encapsulation IP Mode Ethernet Mode Frame Relay to Ethernet/VLAN Yes Yes Frame Relay to PPP Yes No Frame Relay to ATM AAL5 Yes No Ethernet/VLAN to ATM AAL5 Yes Yes Ethernet to VLAN Yes Yes Ethernet to PPP Yes No 1974_chp10ONLa.fm Page 737 Tuesday, November 14, 2006 10:07 AM 737 Chapter 10: Any Transport over MPLS IP Interworking The benefit of L2VPN interworking in IP mode is that you can provide AToM functionality, even if the encapsulation is different on both sides of the MPLS network MPLS VPN can carry the IP traffic across the MPLS network, but MPLS VPN is a service that carries the IP protocol in a pointto-multipoint fashion, whereas AToM is strictly point-to-point Furthermore, with MPLS VPN, the PE and CE router always interact at Layer 3; an IP routing protocol runs between the two routers With AToM, however, an IP routing protocol never runs between the PE and CE router With AToM, the routing protocol runs between the two CE routers across the pseudowire NOTE IP interworking is also known as routed interworking Figure 10-1 shows how the IP packet is transported across the AToM network The ingress PE router PE1 strips off the Ethernet encapsulation, takes the IP packet, labels it with the tunnel and virtual circuit (VC) label, and switches the packets into the MPLS network The egress PE router PE2 strips off the VC label, encapsulates the IP packet into PPP, and forwards the frame onto the correct interface to the CE router Figure 10-1 Example of IP Interworking: Ethernet to PPP Label 74 Label 88 Label 23 Label 23 Label 23 Ethernet Header Control Word Control Word Control Word PPP Header IP IP IP IP IP Ethernet Loopback 10.200.254.1/32 P Loopback P 10.200.254.4/32 VCID 100 PE1-CE PPP VCID 100 PE1 PE2 FastEth 9/0/0 Serial 4/0/0 Attachment Circuit (AC) Attachment Circuit (AC) PE2-CE Example 10-1 shows you the configuration for the case of Ethernet to PPP interworking IP interworking is simply configured by configuring interworking IP under the pseudowire-class Example 10-1 Ethernet to PPP IP Interworking Example PE1# pseudowire-class one encap sulation mpls 1974_chp10ONLa.fm Page 738 Tuesday, November 14, 2006 10:07 AM L2VPN Interworking Ethernet to PPP IP Interworking Example (Continued) Example 10-1 sequencing both interwork ing ip ! interface FastEthe rnet9/0/0 no ip address x connect 10.200.254.4 100 pw-class one ! PE2# pseudowire-class one encap sulation mpls sequencing both interworking ip ! inte rface Serial4/0/0 no ip a ddress encapsulation ppp x connect 10.200.254.1 100 pw-class one ! PE1#show mpls l2transport vc 100 Local intf Local circuit - - Dest address Fa9/0/0 Ethernet 10.200.254.4 VC ID 100 Status UP PE1#show mpls l2transport vc 100 detail Local interface: Fa9/0/0 up, line protocol up, Ethernet up MPLS VC type is IP, interworking type is IP Destination address: 10.200.254.4, VC ID: 100, VC status: up Output interface: Et0/0/0, imposed label stack {74 23} !output omitted for brevity PE2#show mpls l2transport vc 100 Local intf Local circuit - - - Se4/0/0 PPP PE2#show mpls l2transport vc 100 Dest address 10.200.254.1 VC ID 100 detail Local interface: Se4/0/0 up, line protocol up, PPP up MPLS VC type is IP, interworking type is IP Destination address: 10.200.254.1, VC ID: 100, VC status: up Preferred path: not configured Default path: active Tunnel label: 22, next hop point2point Output interface: Se5/0, imposed label stack {22 24} !output omitted for brevity Status UP 738 1974_chp10ONLa.fm Page 739 Tuesday, November 14, 2006 10:07 AM 739 Chapter 10: Any Transport over MPLS This particular example can lead to an interesting problem On one side of the pseudowire, the AC is a point-to-point medium (PPP), whereas on the other side, it is a broadcast medium (Ethernet) This is a problem for some routing protocols, such as Open Shortest Path First (OSPF) Enhanced Interior Gateway Routing Protocol (EIGRP), however, does not have a problem The EIGRP hello packets are broadcasted to the 224.0.0.10 multicast IP address The two CE routers form an EIGRP neighborship across the pseudowire without special configuration OSPF is unique because it operates differently over point-to-point media than it does over broadcast media If the default OSPF configuration is kept, OSPF does not function correctly across the pseudowire because it behaves in Broadcast mode over the Ethernet AC and in Pointto-Point mode over the PPP AC To solve this problem, configure the Ethernet interface so that OSPF sees it as a point-to-point interface You can this with the command ip ospf network point-to-point on the Ethernet interface of the CE router Example 10-2 shows the configuration needed on the CE routers to get OSPF working in the case of Ethernet to PPP IP interworking Example 10-2 Ethernet to PPP IP Interworking: OSPF PE1-ce# ! interface FastEthernet0/1 ip address 10.100.100.1 255.255.255.0 ip ospf net work point-to-point ! route r ospf 100 log-adjacency-c hanges network 10.0.0.0 255.255.255 area ! PE2-ce# ! interface Serial0/0 ip ad dress 10.100.100.2 255.25 5.255.0 encapsulation pp p ! router ospf 100 log-adja cency-changes network 10.0 0.0 0.255.255.255 area ! PE1-ce#show ip ospf interface fastEthernet 0/1 FastEthernet0/1 is up, line protocol is up Internet Address 10.100.100.1/24, Area Process ID 100, Router ID 10.1.1.1, Network Type POINT_TO_POINT, Cost: Transmit Delay is sec, State POINT_TO_POINT, Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit oob-resync timeout 40 1974_chp10ONLa.fm Page 740 Tuesday, November 14, 2006 10:07 AM L2VPN Interworking Example 10-2 740 Ethernet to PPP IP Interworking: OSPF (Continued) Hello due in 00:00:02 Index 2/2, flood queue length Next 0x0(0)/0x0(0) Last flood scan length is 1, maximum is Last flood scan time is msec, maximum is msec Neighbor Count is 1, Adjacent neighbor count is Adjacent with neighbor 10.100.103.2 Suppress hello for neighbor(s) PE1-ce#show ip ospf neighbor Neighbor ID 10.100.103.2 Pri State FULL/ - Dead Time Address Interface 00:00:39 10.100.100.2 FastEthernet0/1 Example 10-3 shows an AToM network with IP interworking between ATM AAL5 encapsulation on the PE router PE1 and Ethernet VLAN encapsulation on the PE router PE2 Notice that the MTU on the ATM interface has been changed to 1500 (the default is 4470); otherwise, the pseudowire VCID 1000 between the two PE routers would not function because of an MTU mismatch Example 10-3 Ethernet VLAN to ATM AAL5 IP Interworking hostname PE1-ce ! interface ATM2/0.1 point-to-point mtu 1500 ip address 10.100 100.1 255.255.255.0 no a tm enable-ilmi-trap pvc 10 /100 encapsulation aal5 snap ! ! hostname PE2-ce ! interface FastEthe rnet0/1 no ip address ! inte rface FastEthernet0/1.100 encapsulation dot1Q 100 ip address 10.100.100.2 55.255.255.0 ! hostname PE1 ! pseudowire-class one continues 1974_chp10ONLa.fm Page 741 Tuesday, November 14, 2006 10:07 AM 741 Chapter 10: Any Transport over MPLS Example 10-3 Ethernet VLAN to ATM AAL5 IP Interworking (Continued) encapsulation mpls interw orking ip ! interface ATM8/ 0/0 mtu 1500 no ip addres s pvc 10/100 l2transport encapsulation aal5snap x connect 10.200.254.4 1000 pw-class one ! ho stname PE2 ! pseudowire-cla ss one encapsulation mpls interworking ip ! interface FastEthernet4/1/0.100 en capsulation dot1Q 100 xco nnect 10.200.254.1 1000 pw -class one ! PE1#show mpls l2transport vc 1000 detail Local interface: AT8/0/0 up, line protocol up, ATM AAL5 10/100 up MPLS VC type is IP, interworking type is IP Destination address: 10.200.254.4, VC ID: 1000, VC status: up Preferred path: not configured Default path: active Tunnel label: 23, next hop 10.200.200.2 Output interface: Et0/0/0, imposed label stack {23 35} !output trimmed for brevity PE2#show mpls l2transport vc 1000 detail Local interface: Fa4/1/0.100 up, line protocol up, Eth VLAN 100 up MPLS VC type is IP, interworking type is IP Destination address: 10.200.254.1, VC ID: 1000, VC status: up Preferred path: not configured Default path: active Tunnel label: 22, next hop point2point Output interface: Se5/0, imposed label stack {22 16} !output trimmed for brevity PE1#show atm pvc 10/100 ATM8/0/0: VCD: 1, VPI: 10, VCI: 100 UBR, PeakRate: 149760 AAL5-LLC/SNAP, etype:0x0, Flags: 0x10000C20, VCmode: 0x0 1974_chp10ONLa.fm Page 742 Tuesday, November 14, 2006 10:07 AM L2VPN Interworking Example 10-3 742 Ethernet VLAN to ATM AAL5 IP Interworking (Continued) OAM Cell Emulation: not configured Interworking Method: IP Remote Circuit Status = No Alarm, Alarm Type = None !output trimmed for brevity Ethernet Interworking A second form of L2VPN interworking is Ethernet interworking, which is also referred to as bridged interworking When the PE router receives Layer frames, it extracts the Ethernet frame, labels it, and sends it across the MPLS network The advantage of using Ethernet interworking is that you can use integrated routing and bridging (IRB) or routed bridge encapsulation (RBE) on the CE router One benefit of using RBE, for example, is that the Ethernet connectivity becomes alike when using an Interior Gateway Protocol (IGP) that would otherwise have problems dealing with a point-to-point interface on one CE and a multipoint interface on the other CE Of course, just bridging the Ethernet frames is also a possibility Another benefit of using Ethernet as the Interworking mode is that it supports the transport of multiple Layer protocols across the pseudowire, whereas IP interworking does not An example in which Ethernet interworking for AToM is desirable is an enterprise network that has multiple sites interconnected through a service provider that provides the AToM service For technical reasons or even pricing reasons, it might not be possible to have Ethernet encapsulation all the way up to the PE router In those cases, Ethernet can be encapsulated into ATM, Frame Relay, and so on to bring it to the PE router Example 10-4 shows the configuration of the PE routers in an AToM network in which Ethernet interworking exists between VLAN and Ethernet In other words, one PE has a VLAN toward the CE, whereas the other PE has a plain Ethernet link toward the CE The two CE routers can communicate across the AToM network because of the Ethernet i: AT8/0/0 up, line protocol up, ATM AAL5 10/100 up MPLS VC type is Ethernet, interworking type is Ethernet Destination address: 10.200.254.4, VC ID: 1000, VC status: up Preferred path: not configured Default path: active Tunnel label: 23, next hop 10.200.200.2 Output interface: Et0/0/0, imposed label stack {23 22} !output omitted for brevity show mpls l2transport vc 000 detail PE2#s Local interface: Fa4/1/0.100 up, line protocol up, Eth VLAN 100 up MPLS VC type is Ethernet, interworking type is Ethernet Destination address: 10.200.254.1, VC ID: 1000, VC status: up Preferred path: not configured Default path: active Tunnel label: 22, next hop point2point Output interface: Se5/0, imposed label stack {22 16} !output omitted for brevity Example 10-6 shows the Ethernet interworking between ATM AAL5 and Ethernet VLAN again The only difference from the previous example is that the CE router PE1-ce is using IRB now IRB allows for routing of a protocol between routed interfaces and bridge groups on one router IRB creates a Bridge Group Virtual Interface (BVI), which enables the packets to be switched between the routed and bridged interfaces The BVI interface is created so that the routed interfaces have one interface that represents the bridge group on that router Example 10-6 Ethernet VLAN to ATM AAL5 Ethernet Interworking with IRB on the CE hostname PE1-ce ! bridge irb ! 1974_chp10ONLa.fm Page 746 Tuesday, November 14, 2006 10:07 AM L2VPN Inter-Autonomous Networking Example 10-6 746 Ethernet VLAN to ATM AAL5 Ethernet Interworking with IRB on the CE (Continued) interface ATM2/0.1 point-t o-point mtu 1500 bridge-g roup pvc 10/100 encap sulation aal5snap ! ! interface BVI1 mtu 1500 ip address 10.100.100.1 255.255.255.0 ! bridge pr otocol ieee bridge route ip ! hostname PE2-ce ! interf ace FastEthernet0/1.100 e ncapsulation dot1Q 100 ip address 10.100.100.2 255 255.255.0 ! L2VPN Inter-Autonomous Networking So far in this chapter, the MPLS network that has been supporting the AToM service has been one autonomous system (AS) If the MPLS network that provides AToM is split over two or more autonomous systems, the following must be true: ■ The loopback IP prefixes (/32 prefixes) of the PE routers must be known in the other autonomous system(s) These loopback IP prefixes are used by the xconnect commands ■ The targeted Label Distribution Protocol (LDP) session must be set up between the PE routers ■ A label switched path (LSP) must exist between the PE routers 1974_chp10ONLa.fm Page 747 Tuesday, November 14, 2006 10:07 AM 747 Chapter 10: Any Transport over MPLS If these requirements are met, AToM can work across different autonomous systems without a problem Figure 10-2 shows the requirement for L2VPN Inter-Autonomous Networking The link(s) between the autonomous system boundary routers (ASBRs) must carry labeled packets; otherwise, no end-to-end LSP exists between the PE routers That also entails that a label distribution exists between the two ASBRs This can be either an IGP with LDP, or it can be eBGP with label distribution for IPv4 prefixes Figure 10-2 L2VPN Inter-Autonomous Networking: Method Targeted LDP Session CE PE ASBR ASBR PE CE Labeled Packets Autonomous System Autonomous System LSP LSP You can achieve Inter-Autonomous Networking of AToM networks in another way You can connect two autonomous systems by connecting two PE routers, one from each autonomous system These two border routers can share one subinterface or VC between them for each pseudowire they need to transport from one autonomous system to the other Figure 10-3 shows this way of interconnecting the AToM service between two autonomous systems 1974_chp10ONLa.fm Page 748 Tuesday, November 14, 2006 10:07 AM L2VPN Pseudowire Switching L2VPN Pseudowire Switching 748 Figure 10-3 L2VPN Inter-Autonomous Networking: Method Targeted LDP Session CE PE Targeted LDP Session PE-ASBR Autonomous System PE-ASBR Layer Frames PE CE Autonomous System LSP LSP LSP LSP In this scenario, you not need an end-to-end LSP between the PE routers or a targeted LDP session between the PE routers from different autonomous systems The traffic between the ASBRs is not labeled traffic as in the previous scenario, but it is the native Layer traffic The disadvantage of this solution compared to the previous one is that you might need many interfaces between the ASBRs (for example, one interface for each High-Level Data Link Control [HDLC] link transported across autonomous systems) if you have several Layer virtual private networks (VPNs) shared between the two autonomous systems The previous solution, however, needed only one link between the ASBRs that could then carry all labeled packets for all shared pseudowires between the two autonomous systems You can alleviate this disadvantage somewhat if only Ethernet VLANs are shared between the two AToM-enabled autonomous systems In that case, one dot1q trunk between the two ASBRs can carry all the shared VLANs between the two autonomous systems L2VPN Pseudowire Switching A third method for Inter-Autonomous AToM Networking is available L2VPN Pseudowire Switching allows connection of two pseudowire segments The two pseudowire segments are stitched together and form one pseudowire end to end Although two pseudowire segments in one autonomous system can be stitched together by one LSR, the big advantage is the stitching of two 1974_chp10ONLa.fm Page 749 Tuesday, November 14, 2006 10:07 AM 749 Chapter 10: Any Transport over MPLS pseudowire segments from different autonomous systems Look at Figure 10-4, which shows two autonomous systems with one pseudowire segment The two pseudowire segments are stitched together at the ASBR routers, by a third pseudowire segment The three pseudowire segments together form one end-to-end pseudowire Figure 10-4 L2VPN Pseudowire Switching Between Two Autonomous Systems Tunnel Label CE Tunnel Label VC Label VC Label VC Label Control Word Control Word Control Word Frame Frame Frame Targeted LDP Session Targeted LDP Session Targeted LDP Session Loopback 10.100.1.1/32 PE Loopback 10.100.1.3/32 ASBR1 Loopback 10.100.2.1/32 ASBR2 Loopback 10.100.2.3/32 PE HDLC VCID 100 CE HDLC VCID 100 Autonomous System Pseudowire Segment Autonomous System Pseudowire Segment Pseudowire Segment The benefit of this method of Inter-Autonomous AToM Networking is that the PE addresses from one autonomous system not need to be known on all routers in the other autonomous system This is normally necessary for creating one pseudowire end to end The ASBRs need configuration to stitch the two pseudowires together They need to have the point-to-point Layer virtual forwarding instance (VFI) configuration to make this work Under the VFI configuration, the ASBRs have the PEs in the same autonomous system and the ASBRs of the other autonomous system configured as neighbors The PE routers need only the normal AToM configuration One LDP session exists between the two ASBRs as a result of the neighbor statement under the VFI toward the other ASBR This creates a third pseudowire segment between the two ASBRs The packets are then switched between two pseudowire segments on each ASBR The AToM frames are label switched on the link between the ASBRs The ASBRs must have a label binding for the loopback IP address of the other ASBR Therefore, either an IGP with LDP is needed between the two ASBRs, or eBGP is needed for advertising IPv4 prefixes + label 1974_chp10ONLa.fm Page 750 Tuesday, November 14, 2006 10:07 AM L2VPN Pseudowire L2VPN Pseudowire Switching Switching 750 Example 10-7 shows the configuration needed on ASBR1 and how to verify the L2VPN Pseudowire Switching In this example, eBGP for IPv4 is configured with the send-label keyword toward the other ASBR BGP is advertising the ASBR loopback prefix to the other ASBR The encapsulation of the AC at each end is HDLC Example 10-7 L2VPN Pseudowire Switching ! hostname ASBR1 ! pseudowire -class one encapsulation mpls ! l2 vfi l2vpn-one poi nt-to-point neighbor 10.1 00.2.1 100 pw-class one n eighbor 10.100.1.1 100 pw -class one ! ! interface Loop back0 ip address 10.100.1 255.255.255.255 ! interfa ce Serial3/0 description interface to ASBR2 ip add ress 10.3.1.1 255.255.255 mpls bgp forwarding ! rou ter bgp network 10.100 1.3 mask 255.255.255.255 neighbor 10.3.1.2 remote- as neighbor 10.3.1.2 sen d-label ! show vfi l2vpn-one ASBR1#s VFI name: l2vpn-one, type: point-to-point Neighbors connected via pseudowires: Router ID Pseudowire ID 10.100.2.1 100 10.100.1.1 100 show mpls l2transport vc 00 ASBR1#s Local intf Local circuit - - Dest address VC ID Status MPLS PW 10.100.2.1:100 10.100.1.1 100 UP MPLS PW 10.100.1.1:100 10.100.2.1 100 UP show mpls l2transport vc 00 detail ASBR1#s Local interface: MPLS PW 10.100.2.1:100 up continues 1974_chp10ONLa.fm Page 751 Tuesday, November 14, 2006 10:07 AM 751 Chapter 10: Any Transport over MPLS Example 10-7 L2VPN Pseudowire Switching (Continued) Destination address: 10.100.1.1, VC ID: 100, VC status: up Preferred path: not configured Default path: active Next hop: 10.1.2.1 Output interface: Et0/0, imposed label stack {40 72} Create time: 01:26:01, last status change time: 01:15:10 Signaling protocol: LDP, peer 10.100.1.1:0 up MPLS VC labels: local 46, remote 72 Group ID: local 0, remote MTU: local 1500, remote 1500 Remote interface description: Sequencing: receive transparent, send transparent Sequencing resync disabled VC statistics: packet totals: receive 999, send 995 byte totals: receive 84807, send 84535 packet drops: receive 0, seq error 0, send Local interface: MPLS PW 10.100.1.1:100 up Destination address: 10.100.2.1, VC ID: 100, VC status: up Preferred path: not configured Default path: active Next hop: point2point Output interface: Se3/0, imposed label stack {35} Create time: 01:26:02, last status change time: 01:15:11 Signaling protocol: LDP, peer 10.100.2.1:0 up MPLS VC labels: local 73, remote 35 Group ID: local 0, remote MTU: local 1500, remote 1500 Remote interface description: Sequencing: receive transparent, send transparent Sequencing resync disabled VC statistics: packet totals: receive 995, send 999 byte totals: receive 84535, send 84807 packet drops: receive 0, seq error 0, send show mpls l2transport vc 00 PE1#s Local intf Local circuit - - Dest address Se3/0 HDLC 10.100.1.3 VC ID 100 show xconnect peer 10.100 2.1 vcid 100 detail ASBR1#s Legend: XC ST=Xconnect State, S1=Segment1 State, S2=Segment2 State UP=Up, DN=Down, AD=Admin Down, IA=Inactive, NH=No Hardware Status UP 1974_chp10ONLa.fm Page 752 Tuesday, November 14, 2006 10:07 AM Local Switching Example 10-7 752 L2VPN Pseudowire Switching (Continued) XC ST Segment S1 Segment S2 + -+ + -+-UP mpls 10.100.2.1:100 UP mpls 10.100.1.1:100 UP Local VC label 73 Local VC label 46 Remote VC label 35 Remote VC label 72 pw-class: one pw-class: one show xconnect peer 10.100 1.3 vcid 100 detail ASBR2#s Legend: XC ST=Xconnect State, S1=Segment1 State, S2=Segment2 State UP=Up, DN=Down, AD=Admin Down, IA=Inactive, NH=No Hardware XC ST Segment S1 Segment S2 + -+ + -+-UP mpls 10.100.2.3:100 UP mpls 10.100.1.3:100 UP Local VC label 32 Local VC label 35 Remote VC label 73 Remote VC label 73 pw-class: one pw-class: one Local Switching Local switching is a feature whereby the PE router switches the Layer frames without sending them across the MPLS network The Layer frames are never labeled, and as such, this feature has little to with AToM It is mentioned here because it might be useful when AToM is deployed Imagine that a customer has two sites close to each other, but both sites need an independent connection to the AToM network The two sites probably each have one connection to the same PE router of the service provider If Layer traffic needs to be switched between the two sites, it is not necessary to use the MPLS network; the PE router can switch the traffic locally Figure 10-5 shows a PE router with local switching Figure 10-5 Local Switching on the PE Router CE Frame Relay/ ATM/Ethernet/VLAN PE Local Switching CE Frame Relay/ ATM/Ethernet/VLAN P PE 1974_chp10ONLa.fm Page 753 Tuesday, November 14, 2006 10:07 AM 753 Chapter 10: Any Transport over MPLS The encapsulations that local switching supports are ATM, Frame Relay, and Ethernet In some cases, you can even have interworking for local switching, meaning that the encapsulation type is different for both links on the PE router Cisco IOS supports the following interworking for local switching: ■ ATM to Ethernet ■ ATM to Frame Relay You configure Local Switching by using the connect command in Cisco IOS If the two interfaces have a different encapsulation type, the interworking can be IP or Ethernet As seen in some previous examples of interworking, you might want to configure RBE or IRB on the CE routers when the Ethernet interworking is done ATM-to-ATM Local Switching Example 10-8 shows a router configured for ATM-to-ATM Local Switching with encapsulation AAL5 Example 10-8 ATM-to-ATM Local Switching interface a tm 1/0/0 p vc 0/ 100 l2transport encapsul ation aa l5 ! interface a tm 2/0/0 p vc 0/100 l2transpo rt encapsulation aa l5 ! co nnect atm-atm at m 1/0/0 /100 atm 2/0/0 0/100 ATM-to-ATM local switching is also supported for AAL0 (Cell Relay) in VC mode ATM-to-Ethernet Local Switching On a router, you can have Local Switching between ATM and Ethernet VLAN or Ethernet Port mode This local interworking is supported in two modes: IP and Ethernet 1974_chp10ONLa.fm Page 754 Tuesday, November 14, 2006 10:07 AM Local Switching 754 ATM to Ethernet VLAN Example 10-9 shows a router that is configured for local switching between an ATM PVC interface that is configured for AAL5SNAP encapsulation and an Ethernet VLAN The connect command allows local switching between these two interfaces and specifies the interworking type as IP mode Example 10-9 ATM-to-Ethernet VLAN Local Switching ! hostname PE2 ! interface ATM0/0/0 no ip address pvc 10/100 l2transport encapsulation aal5snap ! ! interface FastEthernet4/1/0.100 encapsulation dot1Q 100 ! connect atm-eth ATM0/0/0 10/100 FastEthernet4/1/0.100 interworking ip ! ! show connection name atm-e th PE2#s Connection: - atm-eth Current State: UP Segment 1: ATM0/0/0 AAL5 10/100 up Segment 2: FastEthernet4/1/0.100 up Interworking Type: ip ATM to Ethernet Example 10-10 shows a router that is configured for local switching between ATM and Ethernet The connect command allows local switching between these two interfaces and specifies the interworking type as IP mode Example 10-10 ATM-to-Ethernet Local Switching ! interface ATM0/0/0 no ip address pvc 10/100 l2tra nsport encapsulation aal5 snap ! ! interface FastEthe rnet4/1/0 continues 1974_chp10ONLa.fm Page 755 Tuesday, November 14, 2006 10:07 AM 755 Chapter 10: Any Transport over MPLS Example 10-10 ATM-to-Ethernet Local Switching (Continued) no ip address ! connect atm -eth ATM0/0/0 10/100 Fast Ethernet4/1/0 interworkin g ip ! ! show connection name atm-e th PE2#s Connection: 10 - atm-eth Current State: UP Segment 1: ATM0/0/0 AAL5 10/100 up Segment 2: FastEthernet4/1/0 up Interworking Type: ip ATM-to-Frame Relay Local Switching Example 10-11 shows a router that has two interfaces One is configured for Frame Relay, and the other is an ATM interface that is configured for AAL5SNAP encapsulation The connect command allows local switching between these two interfaces Example 10-11 ATM-to-Frame Relay Local Switching ! interface Serial0/1/0 no ip address encapsulation frame-relay frame-relay i nterface-dlci 300 switche d ! interface ATM8/0/0 no ip address pvc 10/100 l2tra nsport encapsulation aal 5snap ! ! connect atm-fr AT M8/0/0 10/100 Serial0/1/0 300 interworking ip ! ! show connection name atm-f r PE1#s Connection: - atm-fr Current State: UP Segment 1: ATM8/0/0 AAL5 10/100 up Segment 2: Serial0/1/0 300 up Interworking Type: ip 1974_chp10ONLa.fm Page 756 Tuesday, November 14, 2006 10:07 AM Local Switching Frame Relay-to-Frame Relay Local Switching Example 10-12 shows a PE router that has serial interfaces configured for Frame Relay The connect command allows local switching between these two Frame Relay interfaces Example 10-12 Frame Relay-to-Frame Relay Local Switching ! frame-relay switching ! interface Serial0/1/0 no ip address encapsulation frame-relay frame-relay interface-dlci 300 switched frame-relay intf-type dce ! interface Serial0/1/1 no ip address encapsulation frame-relay frame-relay interface-dlci 400 switched frame-relay intf-type dce ! connect fr-fr Serial0/1/0 300 Serial0/1/1 400 ! ! show connection name fr-fr PE1#s 11 fr-fr Se0/1/0 300 Se0/1/1 400 UP 756 ...1974_chp10ONLa.fm Page 736 Tuesday, November 14, 2006 10:07 AM CHAPTER SUPPLEMENT 10 Any Transport over... AAL5 Yes No Ethernet/VLAN to ATM AAL5 Yes Yes Ethernet to VLAN Yes Yes Ethernet to PPP Yes No 1974_chp10ONLa.fm Page 737 Tuesday, November 14, 2006 10:07 AM 737 Chapter 10: Any Transport over MPLS... 10-1 Ethernet to PPP IP Interworking Example PE1# pseudowire-class one encap sulation mpls 1974_chp10ONLa.fm Page 738 Tuesday, November 14, 2006 10:07 AM L2VPN Interworking Ethernet to PPP IP
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