Frame-Mode MPLS Configuration and Verification
In frame mode, MPLS uses a 32-bit label that is inserted between the Layer 2 and Layer 3 headers. Layer 2 encapsulations like HDLC, PPP, Frame Relay, and Ethernet are frame-based except for ATM, which can operate either in frame mode or cell mode.
Basic Frame-Mode MPLS Overview, Configuration, and Verification
Figure 2-1 shows a frame-based MPLS provider network providing MPLS services to sites belonging to Customer A. The frame-based provider’s network consists of routers R1, R2, R3, and R4. R1 and R4 function as Edge Label Switch Routers (LSRs) while R2 and R3 serve as LSRs.
Figure 2-1. Frame-Mode MPLS Provider Network
Figure 2-2 illustrates the configuration flowchart ...