H3C Technologies H3C Intelligent Management Center - Manual (Page 157)

• Traffic Access Management—This function allows you to manage traffic of MPLS TE tunnels to keep
the system performance stable.
Basic concepts
LSP and MPLS TE tunnel
Figure 34 shows the LSPs and MPLS TE tunnels.
Figure 34 LSP and MPLS TE tunnel
• LSP—A label switched path (LSP) is a path through an MPLS network, set up by a signaling
protocol such as LDP, RSVP TE, BGP or CR-LDP. The path is set up based on criteria in the forwarding
equivalence class (FEC), a term used in MPLS to describe a set of packets with similar or identical
characteristics which may be forwarded the same way so they may be bound to the same MPLS
label.
• MPLS TE tunnel—Reroute and transmission over multiple paths may involve multiple LSP tunnels. A
set of such LSP tunnels is called a traffic engineered tunnel (TE tunnel).
In Figure 34 , the LSP along Router B —> Router J —> Router D is a static LSP. It is created to bypass Router
C, which might be a congested node. A static LSP is created along fixed route with fixed nodes, so that
the traffic is forced to go along Router B —> Router J —> Router D.
The tunnel from Router C to Router F is a dynamic tunnel created using dynamic signaling protocol
RSVP-TE. Between Router C and Router F there are several LSPs. Unlike the traditional networks that
perform routing based on only cost values, MPLS TE calculates the shortest path to a node based on cost
values and constraints on the LSP with respect to bandwidth, color, setup/hold priority, explicit path and
other constraints, as well as TEDB. LSP along Router G —> Router I —> Router H is a dynamic LSP. It is
created to protect the link between Router G and Router H so that once the link between Router G and
Router H breaks down, traffic can travel along Router G —> Router I —> Router H.
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