PrefixAnnouncement » History » Revision 2
Revision 1 (Junxiao Shi, 08/13/2018 05:36 AM) → Revision 2/10 (Davide Pesavento, 08/13/2018 11:48 AM)
# Prefix Announcement Protocol The **prefix announcement protocol** allows registering prefixes using a *prefix announcement object*. It is an alternative to NFD [[RibMgmt|RIB Management protocol]]'s `rib/register` verb. ## Prefix Announcement object The **prefix announcement object** is a Data packet that represents an application's intent of registering a prefix toward itself. the application. A Data packet that satisfies the following requirements is a prefix announcement object: * Name starts with the announced prefix, followed by a fixed `prefix-announcement` generic name constant component, followed by a version component and a segment component as defined by the in NDN Naming Conventions. Convention. * ContentType is "prefix announcement". * Content contains zero or more TLV elements. A prefix announcement object, by default, is valid indefinitely. Its **validity period** can be constrained with ValidityPeriod or FreshnessPeriod element. * ValidityPeriod gives the absolute time range in which the prefix announcement remains valid. It is ignored if the receiving node does not have a UnixTime clock. * FreshnessPeriod gives the duration for in which the prefix announcement remains valid. The duration begins when a node or program receives the prefix announcement. * When both ValidityPeriod and FreshnessPeriod are present, the most restricted constraint applies. Trust model of prefix announcement is to be defined by the application. ## Command Verbs ### 'announce' This command announces a prefix using a prefix announcement object. NFD-RIB accepts this command as a [[ndn-cxx:CommandInterest|Command Interest]] with the following syntax: ``` /localhost/nfd/rib/announce/<params-sha256>/<command-interest-components> /localhop/nfd/rib/announce/<params-sha256>/<command-interest-components> ``` The Interest's Parameters element carries the prefix announcement announce object. NFD-RIB converts this command into an equivalent `rib/register` command. Route *origin* is set to "prefix announcement" (number 129). Response is the same as `rib/register` command. ### 'unannounce' There is no 'unannounce' command. Instead, use `rib/unregister` command.