H3C Technologies H3C Intelligent Management Center - Manual (Page 232)

6 Using MPLS Management
MPLS management overview
MPLS management provides a comprehensive MPLS network management solution for metropolitan area
networks. It cooperates with H3C devices to manage MPLS networks. MPLS management provides
various functions, including Device Management, LDP Management, LSP Management, Topology
Management, Label Statistics, and LSP Traffic Statistics.
MPLS management is based on the IMC platform. It adopts the B/S structure. Operators can manage
and monitor MPLS networks anytime and anywhere from the local area network or Internet by using a
browser without having to install any client.
Basic concepts
FEC
As a forwarding technology based on classification, MPLS groups packets with the same characteristics
(such as packets with the same destination or service class) into a class, called a forwarding equivalence
class (FEC). Packets of the same FEC are handled in the same way on an MPLS network. The device
supports classifying FECs according to the network layer destination addresses of packets.
Label
A label is a short, fixed length identifier for identifying a single FEC. A label is locally significant and
must be locally unique.
Figure 117 Format of a label
As shown in Figure 117 , a label is encapsulated between the Layer 2 header and Layer 3 header of a
packet. A label is four bytes in length and consists of the following fields:
• Label—20 bits in length. Label value for identifying a FEC.
• Exp—Three bits in length. Reserved field, usually used for CoS.
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