Table Of Contents
Information About Layer 2 Local Switching
NSF/SSO—Local Switching Overview
Prerequisites for Layer 2 Local Switching
Restrictions for Layer 2 Local Switching
Supported Port Adapters on Cisco 7200 and 7500 Series Routers
Supported Interface Processors on Cisco 7200 Series Routers
Supported Interface Processors on Cisco 7500 Series Routers
Supported Interface Processors on Cisco 12000 Series Routers
How to Configure Layer 2 Local Switching
Configuring ATM-to-ATM PVC Local Switching
Configuring ATM PVC Same-Port Switching
Configuring ATM-to-ATM PVP Local Switching
Configuring ATM PVP Same-Port Switching
Configuring ATM-to-Ethernet (Port Mode) Local Switching
Configuring ATM-to-Ethernet (VLAN Mode) Local Switching
Configuring Ethernet VLAN Same-Port Switching
Configuring Ethernet (Port Mode) to Ethernet VLAN Local Switching
Configuring ATM-to-Frame-Relay Local Switching
Configuring Frame-Relay-to-Frame-Relay Local Switching
Configuring Frame Relay Same-Port Switching
Verifying Layer 2 Local Switching
Configuring NSF/SSO—Local Switching Support
Verifying the SSO/NSF Configuration
Configuration Examples for Layer 2 Local Switching
ATM-to-ATM Local Switching: Example
ATM PVC Same-Port Switching: Example
ATM PVP Same-Port Switching: Example
ATM-to-Ethernet Local Switching: Examples
ATM to Ethernet (Port Mode): Example
Ethernet VLAN Same-Port Switching: Example
ATM-to-Frame-Relay Local Switching: Example
Frame-Relay-to-Frame-Relay Local Switching: Example
Frame Relay DLCI Same-Port Switching: Example
NSF/SSO—Ethernet (Port Mode) to Ethernet VLAN Local Switching: Example
connect (L2VPN local switching)
encapsulation (Layer 2 Local Switching)
Layer 2 Local Switching
The Layer 2 Local Switching feature allows you to switch Layer 2 data between two interfaces on the same router, and in some cases to switch Layer 2 data between two circuits on the same interface port. The interface-to-interface switching combinations supported by this feature are:
•ATM to ATM
•ATM to Ethernet
•ATM to Frame-Relay
•Ethernet to Ethernet VLAN
•Frame Relay to Frame Relay (and since 12.0(28)S, also to Multilink Frame Relay)
The same-port switching feature introduced with Release 12.0(30)S supports the following:
•Same-Port Switching for ATM (PVC and PVP)
•Same-Port Switching for Ethernet VLAN
•Same-Port Switching for Frame Relay
Beginning with Cisco IOS Release 12.0(30)S, cell packing is available during ATM VP or VC local switching—on the Cisco Series 12000 router Engine 3 linecards. For information about how to configure cell-packing, see Any Transport over MPLS.
Feature History of Layer 2 Local Switching
Finding Support Information for Platforms and Cisco IOS Software Images
Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.
Contents
•Information About Layer 2 Local Switching
•Prerequisites for Layer 2 Local Switching
•Restrictions for Layer 2 Local Switching
•How to Configure Layer 2 Local Switching
•Configuration Examples for Layer 2 Local Switching
Information About Layer 2 Local Switching
The following sections provide an introduction to the Layer 2 Local Switching feature:
•NSF/SSO—Local Switching Overview
Local Switching Overview
Local switching allows you to switch Layer 2 data between two interfaces of the same type (for example, ATM to ATM, or Frame Relay to Frame Relay) or between interfaces of different types (for example, Frame Relay to ATM) on the same router. The interfaces can be on the same line card or on two different cards. During these kinds of switching, the Layer 2 address is used, not any Layer 3 address.
Additionally, same-port local switching allows you to switch Layer 2 data between two circuits on the same interface.
NSF/SSO—Local Switching Overview
Nonstop Forwarding (NSF) and Stateful Switchover (SSO) improve the availability of the network by providing redundant route processors and checkpointing of data to ensure minimal packet loss when the primary route processor goes down. NSF/SSO support is available for the following locally switched attachment circuits:
•Ethernet to Ethernet VLAN
•Frame Relay to Frame Relay
When to Use Local Switching
Incumbent local exchange carriers (ILECs) who use an interexchange carrier (IXC) to carry traffic between two local exchange carriers can use Local Switching. Telecom regulations require the ILECs to pay the IXCs to carry that traffic. At times, the ILECs cannot terminate customer connections that are in different local access and transport areas (LATAs). In other cases, customer connections terminate in the same LATA, which may also be on the same router.
For example, company A has more than 50 LATAs across the country and uses three routers for each LATA. Company A uses companies B and C to carry traffic between local exchange carriers. Local switching of Layer 2 frames on the same router might be required.
Similarly, if a router is using, for example, a channelized interface, it might need to switch incoming and outgoing traffic across two logical interfaces that reside on a single physical port. The same-port local switching feature addresses that implementation.
Figure 1 shows a network that using local switching for both Frame Relay to Frame Relay and ATM to Frame Relay local switching.
Figure 1 Local Switching Example
Prerequisites for Layer 2 Local Switching
•You must enable Cisco Express Forwarding (CEF) for the Cisco 7200 series router. You must use CEF or Distributed CEF for the Cisco 7500 series router. (Distributed CEF is enabled already by default on the Cisco 12000 series routers).
•For Frame Relay local switching, you must globally issue the frame-relay switching command.
Restrictions for Layer 2 Local Switching
The following sections list the restrictions for the Layer 2 Local Switching feature:
•Supported Port Adapters on Cisco 7200 and 7500 Series Routers
•Supported Interface Processors on Cisco 7200 Series Routers
•Supported Interface Processors on Cisco 7500 Series Routers
•Supported Interface Processors on Cisco 12000 Series Routers
General Restrictions
•For ATM-to-ATM local switching, the following ATM types are supported for the Layer 2 Local Switching feature:
–ATM adaptation layer 5 (AAL5)
–ATM Single Cell Relay adaptation layer 0 (AAL0), VC mode
–ATM Single Cell Relay VP mode on the Cisco 12000 series routers
–ATM Packed Cell Relay VC and VP modes on the ISE linecard of Cisco 12000 series routers
•In ATM Single Cell Relay AAL0, the ATM virtual path identifier/virtual channel identifier (VPI/VCI) values must match between the ingress and egress ATM interfaces on the Cisco 7200 series and 7500 series routers. If Layer 2 local switching is desired between two ATM VPIs and VCIs whose values do not match and are on two different interfaces, choose ATM AAL5. However, if the ATM AAL5 is using Operation, Administration, and Maintenance (OAM) transparent mode, the VPI and VCI values must match.
•On the Cisco 12000 series routers, VPI/VCI rewrite is supported.
•NSF/SSO for Layer 2 Local Switching is supported on the Cisco 7500 series routers.
Supported Port Adapters on Cisco 7200 and 7500 Series Routers
Layer 2 local switching is supported on the following port adapters in the Cisco 7200 and 7500 series routers:
•PA-FE-TX (single-port Fast Ethernet 100BASE-TX)
•PA-FE-FX (single-port Fast Ethernet 100BASE-FX)
•PA-2FE-TX (dual-port Fast Ethernet 100BASE-TX)
•PA-2FE-FX (dual-port Fast Ethernet 100BASE-FX)
•PA-4E (4-port Ethernet adapter)
•PA-8E (8-port Ethernet adapter)
•PA-4T (4-port synchronous serial port adapter)
•PA-4T+ (enhanced 4-port synchronous serial port adapter)
•PA-8T (8-port synchronous serial port adapter)
•PA-12E/2FE (12-port Ethernet/2-port FE adapter) [Cisco 7200 only]
•PA-GE (Gigabit Ethernet port adapter) [Cisco 7200 only]
•PA-H (single-port HSSI adapter)
•PA-2H (dual-port HSSI adapter)
•PA-MC-8E1 (8-port multichannel E1 G.703/G.704 120-ohm interfaces)
•PA-MC-2EI (2-port multichannel E1 G.703/G.704 120-ohm interfaces)
•PA-MC-8T1 (8-port multichannel T1 with integrated CSUs and DSUs)
•PA-MC-4T1 (4-port multichannel T1 with integrated CSUs and DSUs)
•PA-MC-2T1 (2-port multichannel T1 with integrated CSUs and DSUs)
•PA-MC-8TE1+ (8-port multichannel T1/E1)
•PA-MC-T3 (1-port multichannel T3 interface)
•PA-MC-E3 (1-port multichannel E3 interface)
•PA-MC-2T3+ (2-port enhanced multichannel T3 port adapter)
•PA-MC-STM1 (1-port multichannel STM1 port adapter) [Cisco 7500 only]
•PA-T3 (single-port T3 port adapter)
•PA-E3 (single-port E3 port adapter)
•PA-2E3 (2-port E3 port adapter)
•PA-2T3 (2-port T3 port adapter)
•PA-POS-OC3SML (single-port POS, single-mode, long reach)
•PA-POS-OC3SMI (single-port POS, single-mode, intermediate reach)
•PA-POS-OC3MM (single-port POS, multimode)
•PA-A3-OC3 (1-port ATM OC3/STM1 port adapter, enhanced)
•PA-A3-OC12 (1-port ATM OC12/STM4 port adapter, enhanced) [7500 only]
•PA-A3-T3 (DS3 high-speed interface)
•PA-A3-E3 (E3 medium-speed interface)
•PA-A3-8T1IMA (ATM inverse multiplexer over ATM port adapter with 8 T1 ports)
•PA-A3-8E1IMA (ATM inverse multiplexer over ATM port adapter with 8 E1 ports)
Supported Interface Processors on Cisco 7200 Series Routers
•C7200-I/O-2FE
•C7200-I/O-GE+E (Only the Gigabit Ethernet port of this port adapter is supported.)
•C7200-I/O-FE
Supported Interface Processors on Cisco 7500 Series Routers
•GEIP (Gigabit Ethernet interface processor)
•GEIP+ (Enhanced Gigabit Ethernet interface processor)
Supported Interface Processors on Cisco 12000 Series Routers
•Engine-3 linecards support like-to-like and any-to-any local switching
•8-port OC3 ATM Engine-2 linecards support only like-to-like local switching
•All linecards support FR-to-FR local switching
Unsupported Hardware
The following hardware is not supported:
•Cisco 7200—non-VXR chassis
•Cisco 7500—RSP1 and RSP2
•Cisco 7500—VIP 2-40 and below
•Cisco 12000 series—4-port OC3 ATM Engine-0 linecard
•Cisco 12000 series—4-port OC12 ATM Engine-2 linecard
•Cisco 12000 series—1-port OC12 ATM Engine-0 linecard
•Cisco 12000 series—Ethernet Engine-1, Engine-2, and Engine-4 linecards
How to Configure Layer 2 Local Switching
The following sections explain the tasks you can perform to set up Layer 2 Local Switching:
•Configuring ATM-to-ATM PVC Local Switching (required)
•Configuring ATM PVC Same-Port Switching (required)
•Configuring ATM-to-ATM PVP Local Switching (required)
•Configuring ATM PVP Same-Port Switching (required)
•Configuring ATM-to-Ethernet (Port Mode) Local Switching (required)
•Configuring ATM-to-Ethernet (VLAN Mode) Local Switching (required)
•Configuring Ethernet VLAN Same-Port Switching (required)
•Configuring Ethernet (Port Mode) to Ethernet VLAN Local Switching (required)
•Configuring ATM-to-Frame-Relay Local Switching (required)
•Configuring Frame-Relay-to-Frame-Relay Local Switching (required)
•Configuring Frame Relay Same-Port Switching (required)
•Verifying Layer 2 Local Switching (optional)
•Configuring NSF/SSO—Local Switching Support (optional)
•Verifying the SSO/NSF Configuration (optional)
Configuring ATM-to-ATM PVC Local Switching
Important points:
•You can configure local switching for both ATM AAL5 and ATM AAL0 encapsulation types.
•Creating the ATM PVC is not required. If you do not create a PVC, one is created for you. For ATM-to-ATM local switching, the autoprovisioned PVC is given the default encapsulation type AAL0 cell relay.
•Starting with Release 12.0(30)S, you can configure same-port switching, as detailed in the section "Configuring ATM PVC Same-Port Switching" section.
Use the following steps to configure ATM-to-ATM local switching.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface atmslot/port
4. pvc vpi/vci l2transport
5. encapsulation layer-type
6. exit
7. exit
8. connect connection-name interface pvc interface pvc
DETAILED STEPS
Configuring ATM PVC Same-Port Switching
Use the following steps to configure local PVC switching on a single ATM interface.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface atmslot/subslot/port
4. pvc vpi/vci l2transport
5. encapsulation layer-type
6. exit
7. exit
8. connect connection-name interface pvc interface pvc
DETAILED STEPS
Configuring ATM-to-ATM PVP Local Switching
Use the following steps to configure ATM-to-ATM PVP local switching.
(Starting with Release 12.0(30)S, you can configure same-port switching, as detailed in the "Configuring ATM PVP Same-Port Switching" section.)
SUMMARY STEPS
1. enable
2. configure terminal
3. interface atmslot/port
4. atm pvp vpi l2transport
5. exit
6. exit
7. connect connection-name interface pvp interface pvp
DETAILED STEPS
Configuring ATM PVP Same-Port Switching
Use the following steps to configure local PVP switching on a single ATM interface.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface atmslot/subslot/port
4. atm pvp vpi l2transport
5. exit
6. exit
7. connect connection-name interface pvp interface pvp
DETAILED STEPS
Configuring ATM-to-Ethernet (Port Mode) Local Switching
Important points:
•Creating the ATM PVC is not required. If you do not create a PVC, one is created for you. For ATM-to-Ethernet local switching, the autoprovisioned PVC is given the default encapsulation type AAL5SNAP.
•ATM-to-Ethernet local switching supports both the IP and Ethernet interworking types.
•ATM-to-Ethernet local switching supports the following encapsulation types:
–ATM-to-Ethernet with IP interworking: AAL5SNAP, AAL5MUX
–ATM-to-Ethernet with Ethernet interworking: AAL5SNAP
Use the following steps to configure local switching between ATM and Ethernet port mode.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface atmslot/port
4. pvc vpi/vci l2transport
5. encapsulation layer-type
6. exit
7. exit
8. interface fastethernetslot/port
9. exit
10. connect connection-name interface pvc interface interworking interworking-type
DETAILED STEPS
Configuring ATM-to-Ethernet (VLAN Mode) Local Switching
Important points:
•Creating the ATM PVC is not required. If you do not create a PVC, one is created for you. For ATM-to-Ethernet Local Switching, the autoprovisioned PVC is given the default encapsulation type AAL5SNAP.
•ATM-to-Ethernet Local Switching supports both the IP and Ethernet interworking types.
•ATM-to-Ethernet Local Switching supports the following encapsulation types:
–ATM-to-Ethernet with IP interworking: AAL5SNAP, AAL5MUX
–ATM-to-Ethernet with Ethernet interworking: AAL5SNAP
•The VLAN header is removed from frames that are received on an Ethernet subinterface.
Use the following steps to configure local switching for ATM to Ethernet in VLAN mode.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface atmslot/port
4. pvc vpi/vci l2transport
5. encapsulation layer-type
6. exit
7. interface fastethernetslot/port/subint
8. encapsulation dot1q vlan-id
9. exit
10. connect connection-name interface pvc interface interworking interworking-type
DETAILED STEPS
Configuring Ethernet VLAN Same-Port Switching
Use the following steps to configure switching from one VLAN to another VLAN on the same Ethernet or FastEthernet port.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface fastethernetslot/port.subinterface-number
4. encapsulation dot1q vlan-id
5. exit
6. interface fastethernetslot/port.subinterface-number
7. encapsulation dot1q vlan-id
8. exit
9. connect connection-name interface interface
DETAILED STEPS
Configuring Ethernet (Port Mode) to Ethernet VLAN Local Switching
This section explains how to configure local switching for Ethernet (port mode) to Ethernet VLAN.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface fastethernetslot/port
4. interface fastethernetslot/port/subint
5. encapsulation dot1q vlan-id
6. exit
7. connect connection-name fastethernetinterface_1 fastethernetinterface_2 interworking interworking-type
DETAILED STEPS
Configuring ATM-to-Frame-Relay Local Switching
ATM-to-Frame-Relay local switching was introduced in an earlier release of Cisco IOS software. Now you use the interworking ip keyword for configuring ATM-to-Frame-Relay local switching.
FRF.8 Frame-Relay-to-ATM service interworking functionality is not supported. Frame Relay discard-eligible (DE) bits do not get mapped to ATM cell loss priority (CLP) bits, and forward explicit congestion notification (FECN) bits do not get mapped to ATM explicit forward congestion indication (EFCI) bits.
For additional information about ATM-to-Frame-Relay Local Switching, see the "Configuring Frame Relay-ATM Interworking" section of the Cisco IOS Wide Area Networking Configuration Guide.
Creating the PVC is not required. If you do not create a PVC, one is created for you. For ATM-to-Ethernet local switching, the automatically provisioned PVC is given the default encapsulation type AAL5SNAP.
ATM-to-Frame-Relay Local Switching supports the following encapsulation types:
•AAL5SNAP
•AAL5NLPID (Cisco 12000 series uses AAL5MUX instead, for IP interworking)
SUMMARY STEPS
1. enable
2. configure terminal
3. interface atmslot/port
4. pvc vpi/vci l2transport
5. encapsulation layer-type
6. exit
7. interface serialslot/port
8. encapsulation frame-relay [cisco | ietf]
9. frame-relay interface-dlci dlci switched
10. exit
11. connect connection-name interface pvc interface dlci interworking interworking-type
DETAILED STEPS
Configuring Frame-Relay-to-Frame-Relay Local Switching
For background information about Frame-Relay-to-Frame-Relay Local Switching, see the Distributed Frame Relay Switching feature module.
With Release 12.0(30)S, you can switch between virtual circuits on the same port, as detailed in the "Configuring Frame Relay Same-Port Switching" section.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip cef [distributed]
4. frame-relay switching
5. interface type number
6. encapsulation frame-relay [cisco | ietf]
7. frame-relay interface-dlci dlci switched
8. exit
9. connect connection-name interface dlci interface dlci
DETAILED STEPS
Configuring Frame Relay Same-Port Switching
Use the following steps to configure local Frame Relay switching on a single interface.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip cef [distributed]
4. frame-relay switching
5. interface type number
6. encapsulation frame-relay [cisco | ietf]
7. frame-relay intf-type [dte | dce | nni]
8. frame-relay interface-dlci dlci switched
9. exit
10. connect connection-name interface dlci interface dlci
DETAILED STEPS
Verifying Layer 2 Local Switching
To verify configuration of the Layer 2 Local Switching feature, use the following commands on the provider edge (PE) router.
SUMMARY STEPS
1. show connection
2. show atm pvc
3. show frame-relay pvc
Step 1 show connection
The show connection command displays the local connection between an ATM interface and a Fast Ethernet interface.
Router# show connection name atm-eth-con
ID Name Segment 1 Segment 2 State==================================================================1 atm-eth-con ATM0/0/0 AAL5 0/100 FastEthernet6/0/0 UPThis exampledisplays the local connection between an ATM interface and a serial interface.
Router# show connection name atm-fr-con
ID Name Segment 1 Segment 2 State==================================================================1 atm-fr-con ATM0/0/0 AAL5 0/100 Serial1/0/0 16 UPThis example displays a same-port connection on a serial interface.
Router# show connection name same-port
ID Name Segment 1 Segment 2 State==================================================================1 same-port Serial1/1/1 101 Serial1/1/1 102 UPStep 2 show atm pvc
The show atm pvc command shows that interface ATM3/0 is UP.
Router# show atm pvc
VCD/ Peak Avg/Min BurstInterface Name VPI VCI Type Encaps SC Kbps Kbps Cells Sts3/0 10 1 32 PVC FRATMSRV UBR 155000 UPStep 3 show frame-relay pvc
The show frame-relay pvc command shows a switched Frame Relay PVC:
Router # show frame-relay pvc 16
PVC Statistics for interface POS5/0 (Frame Relay NNI)DLCI = 16, DLCI USAGE = SWITCHED, PVC STATUS = UP, INTERFACE = POS5/0LOCAL PVC STATUS = UP, NNI PVC STATUS = ACTIVEinput pkts 0 output pkts 0 in bytes 0out bytes 0 dropped pkts 100 in FECN pkts 0in BECN pkts 0 out FECN pkts 0 out BECN pkts 0in DE pkts 0 out DE pkts 0out bcast pkts 0 out bcast bytes 0switched pkts 0Detailed packet drop counters:no out intf 0 out intf down 100 no out PVC 0in PVC down 0 out PVC down 0 pkt too big 0pvc create time 00:25:32, last time pvc status changed 00:06:31
Troubleshooting Tips
You can troubleshoot Layer 2 local switching using the following commands on the PE router:
•show connection
Configuring NSF/SSO—Local Switching Support
This feature provides SSO/NSF support for Local Switching of the following attachment circuits on the same router:
•Ethernet (port mode) to Ethernet VLAN
•Frame Relay to Frame Relay
For information about configuring SSO/NSF on the route processors, see the Stateful Switchover feature module.
Verifying the SSO/NSF Configuration
To verify that the NSF/SSO—Layer 2 Local Switching Support is working correctly, use the following procedure:
Step 1 Issue the ping command or initiate traffic between the two CE routers.
Step 2 Force the switchover from the active RP to the standby RP by using the redundancy force-switchover command. This manual procedure allows for a "graceful" or controlled shutdown of the active RP and switchover to the standby RP. This graceful shutdown allows critical cleanup to occur.
Step 3 Issue the show connect all command to ensure that the Layer 2 Local Switching connection on the dual RP is operating.
Router # show connect all
ID Name Segment 1 Segment 2 State2 Eth-Vlan1 Fa1/1/1 Fa6/0/0/0.1 UPStep 4 Check the ping buffer from the CE router to verify that the contiguous packet outage was minimal during the switchover.
Configuration Examples for Layer 2 Local Switching
This section provides the following configuration examples:
•ATM-to-ATM Local Switching: Example
•ATM PVC Same-Port Switching: Example
•ATM PVP Same-Port Switching: Example
•ATM-to-Ethernet Local Switching: Examples
•Ethernet VLAN Same-Port Switching: Example
•ATM-to-Frame-Relay Local Switching: Example
•Frame-Relay-to-Frame-Relay Local Switching: Example
•Frame Relay DLCI Same-Port Switching: Example
•NSF/SSO—Ethernet (Port Mode) to Ethernet VLAN Local Switching: Example
ATM-to-ATM Local Switching: Example
The following example shows local switching on ATM interfaces configured for AAL5:
interface atm 1/0/0pvc 0/100 l2transportencapsulation aal5interface atm 2/0/0pvc 0/100 l2transportencapsulation aal5connect aal5_conn atm 1/0/0 0/100 atm 2/0/0 0/100ATM PVC Same-Port Switching: Example
The following example shows same-port switching between two PVCs on one ATM interface:
interface atm 1/0/0pvc 0/100 l2transportencapsulation aal5pvc 0/200 l2transportencapsulation aal5connect conn atm 1/0/0 0/100 atm 1/0/0 0/200ATM PVP Same-Port Switching: Example
The following example shows same-port switching between two PVPs on one ATM interface:
interface atm 1/0/0atm pvp 100 l2transportatm pvp 200 l2transportconnect conn atm 1/0/0 100 atm 1/0/0 200ATM-to-Ethernet Local Switching: Examples
ATM-to-Ethernet local switching terminates an ATM frame to an Ethernet/VLAN frame over the same PE router. Two interworking models are used: Ethernet mode and IP mode.
ATM to Ethernet VLAN: Example
The following example shows an Ethernet interface configured for Ethernet VLAN, and an ATM PVC interface configured for AAL5 encapsulation. The connect command allows local switching between these two interfaces and specifies the interworking type as Ethernet mode.
interface fastethernet6/0/0.1encapsulation dot1q 10interface atm 2/0/0pvc 0/400 l2transportencapsulation aal5connect atm_ethvlan_con atm 2/0/0 0/400 fastethernet6/0/0.1 interworking ethernetATM to Ethernet (Port Mode): Example
The following example shows an Ethernet interface configured for Ethernet and an ATM interface configured for AAL5SNAP encapsulation. The connect command allows local switching between these two interfaces and specifies the interworking type as IP mode.
interface atm0/0/0pvc 0/100 l2transportencapsulation aal5snapinterface fastethernet6/0/0connect atm_eth_con atm0/0/0 0/100 fastethernet6/0/0 interworking ipEthernet VLAN Same-Port Switching: Example
The following example shows same-port switching between two VLANs on one Ethernet interface:
interface fastethernet0/0.1encapsulation dot1q 1interface fastethernet0/0.2encapsulation dot1q 2connect conn FastEthernet0/0.1 FastEthernet0/0.2ATM-to-Frame-Relay Local Switching: Example
The following example shows a serial interface configured for Frame Relay and an ATM interface configured for AAL5SNAP encapsulation. The connect command allows local switching between these two interfaces.
interface serial1/0encapsulation frame-relayinterface atm1/0pvc 7/100 l2transportencapsulation aal5snapconnect atm_fr_conn atm1/0 7/100 serial1/0 100 interworking ipFrame-Relay-to-Frame-Relay Local Switching: Example
The following example shows serial interfaces configured for Frame Relay. The connect command allows local switching between these two interfaces.
frame-relay switchingip cef distributedinterface serial3/0/0encapsulation frame-relayframe-relay interface-dlci 100 switchedframe-relay intf-type dceinterface serial3/1/0encapsulation frame-relay ietfframe-relay interface-dlci 200 switchedframe-relay intf-type dceconnect fr_con serial3/0/0 100 serial 3/1/0 200Frame Relay DLCI Same-Port Switching: Example
The following example shows same-port switching between two data links on one Frame Relay interface:
interface serial1/0encapsulation frame-relayframe-relay int-type nniconnect conn serial/0 100 serial1/0 200NSF/SSO—Ethernet (Port Mode) to Ethernet VLAN Local Switching: Example
The following configuration uses the network topology shown in Figure 2.
Figure 2 NSF/SSO—Layer 2 Local Switching Support : Ethernet to Ethernet VLAN
Configuring the CE Interfaces to Connect to the PE1 Router: Example
Configuring the PE1 Router with NSF/SSO and PE Interfaces to the CE Routers
Configuring ICMP Router Discovery Protocol on the CE Routers: Example
This example configures ICMP router discovery protocol (IRDP) on the CE router for Interworking IP for ARP mediation.
CE1 CE2interface FastEthernet3/1/0
ip irdp
ip irdp maxadvertinterval 0
interface FastEthernet4/0.1
ip irdp
ip irdp maxadvertinterval 0
Configuring OSPF on the CE Routers
Configuring Local Switching on the PE1 Router
Additional References
The following sections provide references related to the Layer 2 Local Switching feature.
Related Documents
Standards
MIBs
RFCs
Technical Assistance
Command Reference
This section documents new and modified commands only.
•connect (L2VPN local switching)
•encapsulation (Layer 2 Local Switching)
connect (L2VPN local switching)
To create Layer 2 data connections between two ports on the same router, use the connect command in global configuration mode. To remove such connections, use the no form of this command.
connect connection-name interface [dlci | pvc| pvp] interface [dlci | pvc | pvp] [interworking interworking-type]
no connect connection-name interface [dlci | pvc| pvp] interface [dlci | pvc | pvp] [interworking interworking-type]
Syntax Description
Defaults
No default behavior or values
Command Modes
Global configuration
Command History
Examples
The following example shows an Ethernet interface configured for Ethernet, plus an ATM interface configured for AAL5SNAP encapsulation. The connect command allows local switching between these two interfaces and specifies the interworking type as IP mode.
Router(config)# interface atm0/0/0
Router(config-if)# pvc 0/100 l2transport
Router(cfg-if-atm-l2trans-pvc)# encapsulation aal5snap
Router(config)# interface fastethernet6/0/0.1
Router(config-subif)# encapsulation dot1q 100
Router(config)# connect atm_eth_con atm0/0/0 0/100 fastethernet6/0/0.1 interworking ip
Related Commands
encapsulation (Layer 2 Local Switching)
To configure the ATM adaptation layer (AAL) for a Layer 2 local switching ATM permanent virtual circuit (PVC), use the encapsulation command in ATM PVC L2transport configuration mode. To remove an encapsulation from a PVC, use the no form of this command.
encapsulation layer-type
no encapsulation layer-type
Syntax Description
layer-type
Adaptation layer type. Possible values are:
aal5
aal0
aal5snap
aal5mux
aal5nlpid (not on Cisco 12000 series)
Defaults
If you do not create a PVC, one is created for you. The default encapsulation types for autoprovisioned PVCs are as follows:
•For ATM-to-ATM local switching, the default encapsulation type for the PVC is AAL0.
•For ATM-to-Ethernet or ATM-to-Frame-Relay, the default encapsulation type for the PVC is AAL5SNAP.
Command Modes
ATM PVC L2transport configuration
Command History
Usage Guidelines
The pvc command and the encapsulation command work together. The use of these commands with Layer 2 local switching is slightly different from the use of these commands with other applications. The following list highlights the differences:
•For Layer 2 local switching, you must add the l2transport keyword to the pvc command. The l2transport keyword enables the PVC to transport Layer 2 packets.
•The Layer 2 local switching encapsulation command works only with the pvc command. You cannot create switched virtual circuits or VC bundles to transport Layer 2 packets. You can only use PVCs to transport Layer 2 packets.
The following table shows the encapsulation types supported for each transport type:
Examples
The following example shows how to configure a PVC to transport AAL0 packets for Layer 2 local switching:
pvc 1/100 l2transportencapsulation aal0Related Commands
show connection
To display the status of interworking connections, use the show connection command in EXEC mode.
show connection [all | element | id ID | name name | port port]
Syntax Description
Command Modes
EXEC
Command History
Examples
The following example shows the local interworking connections on a router:
Router# show connection
ID Name Segment 1 Segment 2 State========================================================================1 conn1 ATM 1/0/0 AAL5 0/100 ATM 2/0/0 AAL5 0/100 UP2 conn2 ATM 2/0/0 AAL5 0/300 Serial0/1 16 UP3 conn3 ATM 2/0/0 AAL5 0/400 FA 0/0.1 10 UP4 conn4 ATM 1/0/0 CELL 0/500 ATM 2/0/0 CELL 0/500 UP5 conn5 ATM 1/0/0 CELL 100 ATM 2/0/0 CELL 100 UPTable 1 describes the significant fields shown in the display.
Related Commands
Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
Copyright © 2006 Cisco Systems, Inc. All rights reserved.