Elastic IP addresses provide a static, reachable IP that can dynamically shift between different locations, ensuring seamless connectivity even when underlying network paths change. In traditional networking, this is commonly used in cloud environments or disaster recovery setups.
In an MPLS (Multiprotocol Label Switching) environment, an elastic IP can be implemented by leveraging the dynamic nature of MPLS labels and routing protocols such as BGP (Border Gateway Protocol) to ensure that a single IP address can move between different endpoints.
MPLS Implementation of an Elastic IP
Use of BGP for Route Advertisement
Assign a public or private IP address to a virtual loopback interface within the MPLS core.
Advertise this IP via BGP to all MPLS-connected locations.
When a site fails, another site can advertise the same IP, shifting the traffic dynamically.
Traffic Engineering with MPLS Labels
The MPLS network ensures that packets destined for the elastic IP always take the optimal path based on TE (Traffic Engineering) constraints.
This allows seamless failover without needing to reconfigure end devices.
Redundancy and Failover
The use of LDP (Label Distribution Protocol) and RSVP-TE (Resource Reservation Protocol-Traffic Engineering) ensures high availability.
If a site hosting the elastic IP fails, another site can immediately take over the IP by dynamically advertising it.
Duplicating the Elastic IP Concept in SD-WAN
Modern SD-WAN solutions, such as Fusionās SD-WAN, can replicate the benefits of an elastic IP using a hub-and-spoke architecture with intelligent traffic steering and dynamic route failover.
SD-WAN Implementation of an Elastic IP
Hub-and-Spoke Design for IP Anchoring
In an SD-WAN environment, a hub site (or multiple hubs) can be used to anchor the elastic IP.
Spokes (branch locations) dynamically route traffic through the hub, ensuring that the elastic IP remains consistent.
BGP or OSPF Route Redistribution
SD-WAN appliances at branch sites redistribute routes learned from the hub, ensuring all locations use the same elastic IP.
If the primary hub goes down, the SD-WAN overlay automatically fails over to a secondary hub advertising the same IP.
Path Selection and Failover Mechanisms
Fusionās path determination algorithms ensure traffic always takes the best-performing WAN path.
Packet-based load balancing means that failover occurs seamlessly without requiring a change in session states.
Cloud Native Elasticity
Unlike MPLS, which relies on label-switched paths, Fusionās SD-WAN uses cloud-native route orchestration to reroute traffic dynamically.
The Antares portal provides real-time visibility into routing changes, ensuring that failover and redundancy are managed effectively.
Why SD-WAN is a Better Alternative
MPLS requires complex BGP configurations, whereas SD-WAN automates route management with policy-driven intelligence.
MPLS has high costs and long deployment times, while SD-WAN can be deployed rapidly using Jugglerās ZTP provisioning.
SD-WAN provides superior visibility and control, allowing businesses to monitor and manage failover scenarios dynamically.
By leveraging Fusionās SD-WAN, businesses can implement a cost-effective, highly available elastic IP solution without the operational overhead of MPLS. This makes SD-WAN the preferred choice for modern networks requiring resilience, scalability, and cloud integration.
