Avaya Configuring IP Services Manuel d'utilisateur Page 216

  • Télécharger
  • Ajouter à mon manuel
  • Imprimer
  • Page
    / 466
  • Table des matières
  • MARQUE LIVRES
  • Noté. / 5. Basé sur avis des utilisateurs
Vue de la page 215
Configuring IP Services
5-12
You set values in BGP-3 accept and announce policy parameters to match and, in
some cases, to override the attribute values contained in inbound and outbound
update messages.
For details about BGP-3 accept policy parameters, see “BGP-3-Specific Accept
Policy Parameters” on page 9-14.
For details about BGP-3 announce policy parameters, see “BGP-3-Specific
Announce Policy Parameters” on page 9-38.
BGP-4 Update Message Format
The BGP-4 update message has the same format and contains the same mandatory
attributes as the BGP-3 update message with the following additions.
In place of the Unreachable attribute that BGP-3 includes as part of the path
attribute description, the BGP-4 update includes an Unreachable field. This
field specifies destinations that have become unreachable.
In place of the BGP-3 optional attributes, a BGP-4 update message can
include the optional attributes described in Table 5-2.
Note: For BGP-3, only natural class networks or the default route (0.0.0.0)
can be advertised. BGP-3 assumes that each advertised network is a natural
class network (A, B, or C) based on its high-order bits. It cannot advertise
subnets or supernets.
Table 5-2. BGP-4 Optional Path Attributes
Attribute Description
Multi-Exit Discriminator Optional attribute used to choose between paths to
the destinations listed.
Local Preference Optional attribute allowing AS border routers to
indicate the preference they have assigned to a
chosen route when advertising it to IBGP peers.
Atomic Aggregate Optional attribute used to ensure that certain network
layer reachability information (NLRI) is not
deaggregated.
(continued)
Vue de la page 215
1 2 ... 211 212 213 214 215 216 217 218 219 220 221 ... 465 466

Commentaires sur ces manuels

Pas de commentaire