VLAN-Aware-Bundle BGP-EVPN

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Interface Type Used in Datacenter? Scalability Typical Use Case
VLAN-Based Less Low/Medium Small DC, MPLS EVPN
VLAN Bundle No (Not recommended) High but no separation Metro Ethernet SP
VLAN-Aware Bundle YES, MOST WIDELY USED Very High Modern VXLAN/EVPN DC


EVPN supports three service models for L2 services. They define how VLANs map to EVPN instances and how NLRI is encoded.

A. VLAN-Based Service Interface (VSI-1:1)

  • One VLAN = One EVI (one bridge-domain)

  • Each VLAN/VNI has its own Route-Distinguisher (RD), Route-Target (RT), MAC table, etc.

  • Most granular, simpler to isolate.

✔ Widely used in multi-tenant DC EVPN-VXLAN.


B. VLAN-Bundle Service Interface (port-based)

  • Multiple VLANs on a port mapped to one single BD/EVI.

  • The system DOES NOT track which MAC belongs to which VLAN → all treated as a single broadcast domain.

  • Rare in modern DCs.

✔ Used sometimes in L2VPN service provider networks (Port-based E-LAN).


C. VLAN-Aware Bundle Service Interface (sub-net based)

  • Many VLANs mapped under one EVI, but each VLAN maintains separation.

  • Think: "One tenant = one EVI, multiple VLANs inside that tenant."

  • EVPN route-types carry Ethernet Tag ID to identify VLAN.

✔ Widely used in large multi-VLAN tenants, MPLS EVPN, brownfield metro-EVPN.


How NLRI differs between VLAN / Bundle / VLAN-Aware

VLAN-Based (1 VLAN = 1 EVI)

  • Ethernet Tag ID = 0

  • VLAN/VNI identified by RT/RD per EVI

  • Very simple.

VLAN-Bundle

  • Multiple VLANs share one EVI

  • Ethernet Tag ID = 0

  • No VLAN separation inside EVPN.

VLAN-Aware Bundle

  • One EVI per tenant

  • Many VLANs separated inside EVPN

  • Ethernet Tag ID = VLAN-ID

  • Most fields include Tag-ID.


Per-EVI Type-1 routes are used ONLY in the VLAN-Aware Bundle service model.
They are not used in VLAN-Based service model.

✔ Mass-withdrawal in VLAN-based EVPN is handled using Route-Type 1 Per-ESI.

✔ No VLAN-ID is carried in Per-ESI RT-1.

✔ All MAC/IP routes tied to that ESI across all VLANs/L2VNIs are withdrawn.

✔ Per-EVI is not required for VLAN-based service interface.

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