Key Criteria for Evaluating Edge and Core Routing Solutionsv1.0

1. Summary

Today’s networking conversations focus heavily on modern solutions that leverage network function virtualization, software-defined networking (SDN), integrated security, and as-a-service delivery models. These technologies rely on virtualization and are built upon existing physical networking infrastructure. However, all these advanced networking technologies are available today only because of the modernization of edge and core routers. Even if these appliances have not moved much beyond their initial scope of delivering packets to their destination, new developments around disaggregation, automation, and orchestration are the key features that have enabled the network to be abstracted and become part of DevOps pipelines.

While edge and core routers are similar in the sense that they both forward network traffic, they sit in different places in network topologies and have different functions in terms of both hardware and software.

As the name implies, edge routers are those that reside at the topological edge of a network as the last appliance managed by an organization before connecting to an external network, such as the internet. Edge routers, by the nature of their use cases, can have different target deployments, such as aggregation, data center, service provider edge, and customer edge. Core routers are large appliances that can route large amounts of traffic within a network.

There are several differences between edge and core router appliances, including:

• Size and throughput: Edge routers are generally smaller and have lower throughput compared to core routers.
• Performance and features: Edge routers handle less traffic, but they can offer features such as traffic filtering, quality of service (Qos), encryption, and access controls. Core routers handle large amounts of traffic, and most of their computational power and memory are allocated to routing.
• Required power: To support greater throughput, core routers typically require more power than edge routers.
• Price: Core routers are generally more expensive than edge routers because of the higher-speed interfaces and higher overall throughput they support.

The implications of hardware for routers are fairly straightforward—a larger chassis with more cards, a greater number of ports, and higher port speeds will result in a higher capacity, as well as higher costs.

Software implications depend on the router’s network operating system (NOS). Deployment and management of network devices need to be standardized at a software level. Edge and core router vendors are now offering generalized NOSs that run only the components the router needs. For example, the same NOS can run QoS functions on an edge router, but not on a core router.

For routers to deliver on the scalability requirements of modern enterprises and service providers, they need to be provisioned, configured, and managed remotely. This is now supported using several relatively new features such as service-layer APIs, support for YANG models with programmatic provisioning and real-time telemetry data, zero-touch provisioning (ZTP), integration of scripting languages, configuration management, software delivery and deployment through artifacts called Golden ISOs, and even support for containers.

The GigaOm Key Criteria and Radar reports provide an overview of the edge and core routing market, identify capabilities (table stakes, key criteria, and emerging technologies) and non-functional requirements (evaluation metrics) for selecting an edge and core routing solution, and detail vendors and products that excel. These reports give prospective buyers an overview of the top vendors in this sector and help decision-makers evaluate solutions and decide where to invest.