List of Figures

Figure 1: BGP Peers

Figure 2: Internal and External BGP

Figure 3: Interior Gateway Protocols

Figure 4: Routing Without CIDR

Figure 5: Routing with CIDR

Figure 6: Transit Service

Figure 7: Nontransit Service

Figure 8: IPv6 Routing over TCP IPv4

Figure 9: IPv6 Routing over TCP IPv6

Figure 10: Configuring Neighbors

Figure 11: BGP Peer Groups

Figure 12: Using EBGP-Multihop

Figure 13: Prefixes Originating in an AS

Figure 14: Redistributing Routes into BGP

Figure 15: Advertising a Default Route

Figure 16: Setting a Static Default Route

Figure 17: Configuring Aggregate Addresses

Figure 18: Advertising a Route When Another Route is Present

Figure 19: Advertising a Route When Another Route is Absent

Figure 20: Advertising a Default Route When Another Route is Present

Figure 21: Filtering with Access Lists

Figure 22: Filtering Routes with an Access List

Figure 23: Filtering with AS-Path Access Lists

Figure 24: Assigning a Filter List

Figure 25: Route Map Filtering

Figure 26: Communities

Figure 27: Community Lists

Figure 28: Configuring Next-Hop Processing

Figure 29: Next-Hop Behavior for Broadcast Multiaccess Media

Figure 30: Next-Hop Behavior for Nonbroadcast Multiaccess Media

Figure 31: Assigning a Weight to a Neighbor Connection

Figure 32: Configuring the Local-Preference Attribute

Figure 33: The Origin Attribute

Figure 34: AS-Path Attributes

Figure 35: Configuring the MED

Figure 36: Synchronization

Figure 37: Disabling Synchronization

Figure 38: Administrative Distances

Figure 39: Administrative Distance and Synchronization

Figure 40: Backdoor Route

Figure 41: A Fully Meshed Autonomous System

Figure 42: A Confederation of Subautonomous Systems

Figure 43: Simple Route Reflection

Figure 44: Route Reflection: Logical Redundancy

Figure 45: Route Reflection: Physical and Logical Redundancy

Figure 46: BGP Route Reflection

Figure 47: Simple MPLS Domain

Figure 48: Label Switching

Figure 49: Label Stacking

Figure 50: Shim Header

Figure 51: TTL Processing on Incoming MPLS Packets

Figure 52: TTL Processing on Outgoing MPLS Packets

Figure 53: LSP Creation, Downstream-on-Demand, Ordered Control

Figure 54: LSP Creation, Downstream-Unsolicited, Independent Control

Figure 55: Explicit Routing in an MPLS Domain

Figure 56: MPLS Interface Stacking for the Platform Label Space

Figure 57: MPLS Interface Stacking for the Interface Label Space

Figure 58: LDP Tunneled Through an RSVP-TE Core

Figure 59: Flow for Initial Setting of EXP Bits for the First Label Pushed

Figure 60: Flow for Setting EXP Bits for All Pushed Labels

Figure 61: Simple MPLS Domain

Figure 62: FEC Aggregation and Equal-Cost Paths

Figure 63: Bypass Tunnel

Figure 64: Differentiated Services over an MPLS Network

Figure 65: Associations Between PHB ID, EXP Bits, and Traffic Classes/Colors

Figure 66: Signaled Mapping

Figure 67: Sample MPLS L3VPN Topology

Figure 68: ECMP BGP/MPLS VPN Scenario

Figure 69: BGP/MPLS VPN Scenario

Figure 70: BGP/MPLS VPN Components

Figure 71: Route and Label Distribution

Figure 72: Standard and Extended BGP Update Messages

Figure 73: BGP/MPLS VPN Route Exchange

Figure 74: LSP Creation for BGP/MPLS VPN

Figure 75: Traffic Across the MPLS Backbone of a BGP/MPLS VPN

Figure 76: Traffic Across the MPLS Backbone of a BGP/MPLS VPN

Figure 77: IPv6 VPN Services over IPv4 MPLS

Figure 78: Inter-AS Topology with VRFs on Each AS Boundary Router

Figure 79: Inter-AS Topology with End-to-End Stacked MPLS Tunnels

Figure 80: Topology for Three-label Stack Configuration for Inter-AS Option C

Figure 81: Topology for Inter-AS Option C with Route Reflectors

Figure 82: Inter-AS IPv6 VPN Services

Figure 83: Site Connectivity in a Full-Mesh VPN

Figure 84: Route Target Configuration for a Full-Mesh VPN

Figure 85: Site Connectivity in a Hub-and-Spoke VPN

Figure 86: Route Target Configuration for a Hub-and-Spoke VPN

Figure 87: Site Connectivity in an Overlapping VPN

Figure 88: Route Target Configuration for an Overlapping VPN

Figure 89: Overlapping VPNs on a Single PE

Figure 90: Fully Meshed VPNs

Figure 91: Hub-and-Spoke VPN

Figure 92: Import and Export Maps

Figure 93: Configuring Static Routes

Figure 94: BGP/MPLS VPN IBGP Example

Figure 95: BGP/MPLS VPN EIBGP Example

Figure 96: PE-to-CE Session

Figure 97: Network with Potential Routing Loops

Figure 98: Preventing Potential Routing Loops in the Network

Figure 99: Allowing Local AS in VPNv4 Address Family

Figure 100: Topology for Fast Reconvergence by Means of Unique VRF RDs, Before Tunnels Go Down

Figure 101: Topology for Fast Reconvergence by Means of Reachability Checking, After Tunnels Go Down

Figure 102: Static Default Route for Internet Access

Figure 103: Fallback Global Option

Figure 104: Global Import Map Applied to Routes Imported from VRF BGP RIB

Figure 105: BGP Session Between CE Router and Parent VR

Figure 106: BGP Session Between CE Router and Parent VR

Figure 107: Static Route to Shared IP Interface

Figure 108: Global Export Map Applied to Routes Exported from VRF BGP RIB

Figure 109: Carrier-of-Carriers Internet Service

Figure 110: Carrier-of-Carriers VPN Service

Figure 111: Carrier-of-Carrier IPv6 VPNs

Figure 112: IPv6 Tunneled over MPLS-IPv4

Figure 113: IPv6 Tunneled Across IPv4 Domains

Figure 114: OSPF Topology with Backdoor Link

Figure 115: OSPF Sham Link

Figure 116: Layer 2 Services over a Provider’s MPLS Network

Figure 117: Common ISP Network

Figure 118: E Series Router Replacing Remote ATM Switch

Figure 119: AAL5 Pseudowire and MPLS Tunnel

Figure 120: CE-Side MPLS L2VPN Tunnel over LAG

Figure 121: Local Cross-Connect Between Ethernet/VLAN Interfaces

Figure 122: CE-Side Load-Balancing Topology

Figure 123: Sample Frame Relay over MPLS Configuration

Figure 124: MPLS L2VPN Tunnel over VLAN over LAG Configuration Example

Figure 125: MPLS L2VPN Tunnel over LAG Configuration Example

Figure 126: MPLS L2VPN Tunnel over LAG Configuration Example

Figure 127: Ethernet Packet Distribution over Martini Circuits

Figure 128: Martini Circuit with Two Pseudowires Between PE-Facing Routers

Figure 129: Martini Circuit Deployment for Transmission of Multiple ATM VCs over a SIngle Pseudowire

Figure 130: VPLS Sample Topology

Figure 131: Topology for VPLS Configuration Example with BGP Signaling

Figure 132: Topology for VPLS Configuration Example with LDP Signaling

Figure 133: VPWS Sample Topology

Figure 134: VPWS Components

Figure 135: VPWS Cross-Connects

Figure 136: Topology for VPWS Configuration Example