Juniper IGP - CONFIGURATION GUIDE V11.1.X, Configuration Manual

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Supported LSA Types
OSPFv3 supports the following LSA types:
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Router LSA—Describes link state and costs of router links to the area; flooded
within an area only
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Network LSA—Originated by the designated router for every broadcast or
nonbroadcast multiaccess (NBMA) link having two or more attached routers; lists
all routers attached to the link
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Interarea prefix LSA—Known as the type-3 summary LSA in OSPFv2; describes
a prefix external to the area, yet internal to the AS
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Interarea router LSA—Called type 4 summary-LSAs in OSPFv2; describes a path
to a destination OSPF router (that is, an AS boundary router) that is external to
the area, yet internal to the AS
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AS-external LSA—Describes a path to a prefix external to the AS
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Link LSA (new for OSPFv3)—Provides the router’s link-local address to all other
routers attached to the link; informs other routers attached to the link of a list
of IPv6 prefixes to associate with the link; enables the router to assert a collection
of options bits in the Network-LSA to be originated for the link
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Intra-area prefix LSA (new for OSPFv3)—Associates a list of IPv6 address prefixes
with a transit network link by referencing a network LSA, or associates a list of
IPv6 address prefixes with a router by referencing a router LSA
An LSA in OSPFv3 is still identified by its type, link-state ID, and the advertising
router ID. However, the link-state ID (for all LSA types) no longer carries IP address
information. Instead, the LSA carries either an arbitrarily assigned number or an
interface ID.
The link-state ID always has a fixed length of 4 bytes. The LS type field is extended
to 16 bits and encodes LSA flooding scope and specific actions to take when the
router encounters unrecognized LS types.
An IPv6 address, if it is specified in an LSA, is represented by its prefix length, prefix
options, and prefix address.
Unsupported OSPF Components
This release does not support the following OSPF components when implementing
OSPF for IPv6:
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Virtual link
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Not-so-stubby-area (NSSA)
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Nonbroadcast multiaccess (NBMA)
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Remote neighbor
■
Traffic engineering extensions
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Features
JUNOSe 11.0.x IP, IPv6, and IGP Configuration Guide