Ethernet Auto Discovery Route (Type 1)
Ethernet Auto-Discovery (EAD) Routes are
essential for simplifying network configurations and ensuring stable connectivity
within
Border Gateway Protocol (BGP) Ethernet Virtual Private Network (EVPN) multi-homing
architectures. They facilitate the identification and association of Ethernet Segments
(ESs), making network management more intuitive.
The table below outlines the fundamental elements of EAD-ES routes, including the message fields and their descriptions, to clarify each component’s role within the ES route framework.
EAD Sub-type 1 (EAD-ES) Routes
| Message | Description |
|---|---|
| RD (8 Bytes) | A unique identifier that differentiates network segments. |
| Key: ESI (10 Bytes) | The identifier for the ES, unique within the network and shared across VTEPs. |
| Key: Ethernet Tag ID (4 Bytes) | Set to the maximum value to indicate specific tagging behavior. |
| Label/L2VNI | Used for routing; typically set to 0 in this context. |
| Tunnel Encapsulation Extended Community | Defines the tunnel’s encapsulation protocol, ensuring consistent data transport. |
| ES Label Extended Community | Indicates the operational mode of the ES, important for traffic handling. |
| List of EVI-RTs | Carries membership information for all EVIs associated with the ES. |
The table below outlines the fundamental elements of EAD-EVI routes, including the message fields and their descriptions, to clarify each component’s role within the ES route framework.
EAD Sub-type 2 (EAD-EVI) Routes
| Message | Description |
|---|---|
| RD (8 Bytes) | Similar to EAD-ES, it serves as a unique network segment identifier. |
| Key: ESI (10 Bytes) | Identical to EAD-ES, it marks the ES within the network. |
| Key: Ethernet Tag ID (4 Bytes) | Set to 0 to support VLAN-based service models. |
| Label/L2VNI | In MPLS-EVPN, this value is crucial for packet forwarding. |
| Tunnel Encapsulation Extended Community | Specifies the encapsulation protocol for creating tunnels in a multi-homing environment. |
| EVI-RT Extended Community | Targets a specific EVI, providing route targeting information. |