မာတိကာ သို့ သွားရန်

Phase 3 — MPLS & L3VPN

🟢 Phase 3 Live — Validated on Arista cEOS 4.32.0F.

MPLS is how service providers move traffic without every router in the middle needing to know where anything is. Instead of looking up a destination at every hop, routers swap a small fixed label — and the whole path is decided once, at the edge.

L3VPN (RFC 4364) builds on that: many customers, each with their own private routing table (VRF), all sharing one provider backbone with complete isolation.

Course Matrix & Labs

Lab Description Core Protocols & Concepts Status
01 MPLS + LDP Underlay OSPF, LDP Label Distribution, LFIB forwarding state 🟢 Validated
02 Single-AS L3VPN & VRF Isolation VRFs, Route Distinguishers (RD), Route Targets (RT), MP-iBGP VPNv4 🟢 Validated
03 Inter-AS L3VPN Option B Inter-AS MP-eBGP VPNv4, ASBR Label Rewriting, Next-Hop Self 🟢 Validated
04 Inter-AS L3VPN Option C BGP Labeled Unicast (BGP-LU RFC 3107/8277), Multi-hop MP-eBGP 🟢 Validated
05 MPLS L2VPN (VPWS & VPLS) Point-to-Point Pseudowire (EoMPLS RFC 4664), Targeted LDP, VPLS Split-Horizon 🟢 Validated

🏛️ Phase 3 Architecture & Network Topology Overview

graph LR
    subgraph CustSiteA["Customer Site A (VRF RED)"]
        CE1["ce1 (Customer A)<br/>10.100.1.1/24"]
    end

    subgraph ServiceProviderBackbone["Service Provider MPLS Backbone (AS 65000)"]
        PE1["pe1 (PE Router)<br/>Loopback: 2.2.2.2"] <===>|OSPF + LDP| P1["p1 (P Core Router)<br/>Loopback: 1.1.1.1"]
        P1 <===>|OSPF + LDP| PE2["pe2 (PE Router)<br/>Loopback: 3.3.3.3"]
        PE1 -.-|MP-iBGP VPNv4 Peer Session| PE2
    end

    subgraph CustSiteB["Customer Site B (VRF RED)"]
        CE2["ce2 (Customer A)<br/>10.100.2.2/24"]
    end

    CE1 <===>|eBGP / Static| PE1
    PE2 <===>|eBGP / Static| CE2

    classDef ce fill:#e65100,stroke:#ffb74d,color:#ffffff,stroke-width:2px,font-weight:bold;
    classDef pe fill:#1b5e20,stroke:#81c784,color:#ffffff,stroke-width:2px,font-weight:bold;
    classDef p fill:#0d47a1,stroke:#64b5f6,color:#ffffff,stroke-width:2px,font-weight:bold;

    class CE1,CE2 ce;
    class PE1,PE2 pe;
    class P1 p;

Google Network Infrastructure Target Competencies

graph TD
    A["MPLS + LDP Underlay<br/>(OSPF, LDP Distribution, LFIB)"] --> B["Single-AS L3VPN & VRFs<br/>(64-bit RD & Extended RTs)"]
    B --> C["Inter-AS L3VPN Option B<br/>(ASBR Label Swapping & MP-eBGP)"]
    C --> D["Hyperscale Inter-AS Option C<br/>(BGP-LU RFC 3107 & Multi-hop MP-eBGP)"]

    classDef s fill:#1565c0,stroke:#90caf9,color:#ffffff,stroke-width:2px,font-size:14px,font-weight:bold;
    class A,B,C,D s;

Prerequisites

Next Steps & Interview Practice

  • Self-Test Interview Questions — Service Provider & WAN Engineering interview question bank covering MPLS, LDP, PHP, RD/RT, and Inter-AS Options A, B, and C.