architecture
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THE ARCHITECTURE DOES NOT ASSUME THAT THERE IS ONLY A SINGLE LABEL
DISTRIBUTION PROTOCOL. In fact, a number of different label
distribution protocols are being standardized. Existing protocols
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... binding to label distribution peer Ru2.
Whether or not L1 == L2 is not determined by the architecture; this
is a local matter.
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... LABEL IS L, WHETHER THE LABEL WAS PUT THERE BY RU1 OR BY RU2, THEN
THE ARCHITECTURE DOES NOT REQUIRE THAT F1 == F2. In such cases, we
may say that Rd is using a different "label space" for the labels it
distributes to Ru1 than for the labels it distributes to Ru2.
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... label spaces for the same interface. This is not prohibited by the
architecture. However, in such cases the LSR must have some means,
not specified by the architecture ...
... architecture. However, in such cases the LSR must have some means,
not specified by the architecture, of determining, for a particular
incoming label, which label space that label belongs to. For
example, [MPLS-SHIM ...
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This architecture allows the choice between independent control and
ordered control to be a local matter. Since the two methods
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... traffic in the union, is known as "aggregation". The MPLS
architecture allows aggregation. Aggregation may reduce the number
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... particular FEC. The proposed MPLS protocol architecture supports two
options for Route Selection: (1) hop by hop routing ...
... stack it is, it is necessary to define a concrete encoding of the
label stack. The architecture supports several different encoding
techniques; the choice of encoding ...
... encoding when transmitting a packet P to
R3. In general, the MPLS architecture supports LSPs with different
label stack encodings ...
... switches have no capability for translating from
one encoding technique to another. The MPLS architecture therefore
requires that whenever it is possible for two ATM switches ...
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The MPLS architecture accommodates both merging and non-merging LSRs,
but allows for the fact that there may be LSRs ...
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The MPLS architecture supports two ways to distribute labels at
different layers of the hierarchy: Explicit Peering and Implicit
Peering.
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This architecture does not establish hard and fast rules for choosing
which label distribution protocol to use in which circumstances.
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The MPLS architecture supports several variants of each procedure.
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However, the MPLS architecture does not support all possible
combinations of all possible variants. The set of supported
combinations will be described in section 5.2, where the
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... binding for a particular address
prefix to its label distribution peers. The architecture supports
four different distribution procedures.
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... Only the MPLS schemes which are specified below are supported by the
MPLS Architecture. Other schemes may be added in the future, if a
need for them is shown.
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