Currently Used Terminology in Global Routing Operations

1.1. Providing input on the draft:

While this draft is being edited, you may provide suggestions for additional abbreviations and terms to be included at:¶

https://files.measurement.network/apps/forms/s/CMXjrtCPD8QyG6CAWmSLmg4y¶

4.1. General Terms

This section describes general terms used in the context of global routing operations, regardless of context.¶

Operator:

Individual, group of people, or organizational unit responsible for operating BGP speakers, i.e., making administrative changes, as well as defining and setting policies for all BGP speakers within an organization.¶

Router:

In this document, router always refers to a BGP speaker.¶

Global Routing Table:

The set of all routes for an address family that have been announced to external BGP Neighbors.¶

Route Selection:

The process when a BGP speaker applies the locally configured policy to select the best route from multiple available options according to that policy.¶

Network Layer Reachability Information:

General description for network reachability information. In the context of BGP, this usually refers to the complete set of information (prefix, next-hop, attributes, etc.) contained in a BGP update message.¶

Default Free Zone:

Part of the Internet where routers do not cary default routes.¶

4.2. Neighbor Relation Terms

This section lists terms used to describe relationships between different ASes.¶

Cone:

The set of ASes who are either direct downstreams of an AS, or in the cone of any of those ASes; Depending on the context this also includes the joint set of prefixes that may be originated by ASes in a cone.¶

Downstream:

In a direct relationship between two ASes the one receiving upstream from the other. (See: [RFC9234], also known as the customer in a customer-provider relationship.)¶

Mutual Transit:

When two directly connected ASes both advertise a BGP fulltable to each other. (See: [I-D.ietf-sidrops-aspa-verification])¶

Upstream:

In a direct relationship between two ASes the one providing upstream to the other. (See: [RFC9234], also known as the provider in a customer-provider relationship.)¶

Peer:

Two directly connected ASes who only advertise routes they originate or learned from their downstreams to each other. (See: [RFC9234])¶

Providing Transit:

Forwarding packets destined for addresses in an advertised prefix, while advertising a full BGP table or default route to the neighbor.¶

Providing Upstream:

See: Providing Transit¶

Depeering:

Removing sessions with a neighboring AS.¶

Neighbor:

An AS to which an established BGP session exists.¶

4.3. Routing Terms

This section describes terms specific to technical aspects of routing.¶

BGP Speaker:

A device exchanging routes with other BGP speakers using the BGP protocol¶

Full Table:

A routing table containing a route to all prefixes in the GRT but not the default route.¶

Exporting a Prefix:

Advertising a prefix to a neighbor.¶

Importing a Prefix:

Accepting a prefix advertised by a neighbor and considering it for route selection and import into the local AS' routing table.¶

Network edge:

Last routers under the control of an operator.¶

Originating a Prefix:

Anouncing a prefix with an empty AS-Path.¶

Propagating a Prefix:

Announcing a prefix with an non-empty AS-Path including other ASes than the announcing AS.¶

BGP Neighbor:

Also just 'Neighbor'. Two BGP speakers that exchange NLRI using the BGP protocol are neighbors.¶

Peer:

A BGP neighbor, if not used to describe a relationship.¶

Prepending:

Inserting an ASes into the AS_PATH multiple times to influence route selection.¶

Traffic Engineering:

Making changes to properties of imported and exported NLRI to influence route selection, and thereby the flow of traffic.¶

Converging:

Used to describe the process of a BGP speaker evaluating all routes and finding the preferred route for each visible prefix. Reconverging is often also used to describe an ongoing selection process reevaluating all routes sent by neighbors, e.g., after a loss of connectivity to one or multiple neighbors.¶

4.4. Security Terms

This section describes terms used in the context of routing security.¶

Route Flapping:

A route that is constantly announced and widthdrawn or otherwise sees constant change.¶

BGP Hijack / Route Hijack:

When an AS announces a route it is not authorized to announce with the intent of intercepting traffic towards the authorized origin.¶

Route Leak:

When an AS announces a route it is not authorized to announce without malicious intent.¶

Update Storm:

A continuous high volume stream of BGP Updates send to one or multiple neighbors.¶

Cascading Update Storm:

When an update storm traverses beyond directly connected neighbors.¶

Blackholing:

Announcing prefixes grouped by a specific community to inform all neighbors observing the announcement that traffic to the destination should be dropped.¶