Abstract: Gateway devices at different sites of a primary Anycast network provide access to the sites by advertising a first set of Anycast addresses. A secondary shadow Anycast network advertises different second sets of Anycast addresses from the different sites in order to predetermine traffic shifts that occur as a result of changing one or more of the second set of Anycast addresses that are advertised from one or more of the sites. A traffic shifting device may implement a predetermined traffic shift in the primary Anycast network by selecting a particular second set of network addresses that produces a traffic shift at least equal to the predetermined traffic shift, mapping the particular second set of network addresses to a modified first set of addresses, and modifying routing in the primary Anycast network by advertising the modified first set of addresses instead of the first set of addresses.

Abstract: A controller may identify a problematic path from several paths over which to route egress traffic from a site, may determine a threshold amount of traffic to shift from the problematic path, and may implement different potential traffic shifts for shifting similar amounts of traffic as the threshold amount. The controller may provide the labels or header values that different nodes in the site may place in the egress traffic in order to control which path is used to distributed that egress traffic. The controller may modify routing policies affecting different Autonomous System numbers, address prefixes, or other routing parameters to select and/or shift egress traffic, that is associated with those routing parameters and that is about equal to the threshold amount of traffic, from the problematic path to a different path.

Abstract: A controller may identify a problematic path from several paths over which to route egress traffic from a site, may determine a threshold amount of traffic to shift from the problematic path, and may implement different potential traffic shifts for shifting similar amounts of traffic as the threshold amount. The controller may provide the labels or header values that different nodes in the site may place in the egress traffic in order to control which path is used to distributed that egress traffic. The controller may modify routing policies affecting different Autonomous System numbers, address prefixes, or other routing parameters to select and/or shift egress traffic, that is associated with those routing parameters and that is about equal to the threshold amount of traffic, from the problematic path to a different path.

Abstract: Gateway devices at different sites of a primary Anycast network provide access to the sites by advertising a first set of Anycast addresses. A secondary shadow Anycast network advertises different second sets of Anycast addresses from the different sites in order to predetermine traffic shifts that occur as a result of changing one or more of the second set of Anycast addresses that are advertised from one or more of the sites. A traffic shifting device may implement a predetermined traffic shift in the primary Anycast network by selecting a particular second set of network addresses that produces a traffic shift at least equal to the predetermined traffic shift, mapping the particular second set of network addresses to a modified first set of addresses, and modifying routing in the primary Anycast network by advertising the modified first set of addresses instead of the first set of addresses.

Abstract: Gateway devices at different sites of a primary Anycast network provide access to the sites by advertising a first set of Anycast addresses. A secondary shadow Anycast network advertises different second sets of Anycast addresses from the different sites in order to predetermine traffic shifts that occur as a result of changing one or more of the second set of Anycast addresses that are advertised from one or more of the sites. A traffic shifting device may implement a predetermined traffic shift in the primary Anycast network by selecting a particular second set of network addresses that produces a traffic shift at least equal to the predetermined traffic shift, mapping the particular second set of network addresses to a modified first set of addresses, and modifying routing in the primary Anycast network by advertising the modified first set of addresses instead of the first set of addresses.