HP 10500 Series Configuration Manual page 234

Figure 62 Multi-segment PW
CE 1
Multi-segment PWs include intra-domain multi-segment PWs and inter-domain multi-segment PWs.
Intra-domain multi-segment PW
An intra-domain multi-segment PW comprises concatenated PWs within an AS. You can create an
intra-domain multi-segment PW between two PEs that have no public tunnel to each other.
As shown in
between PE1 and PE 2 and a public tunnel between PE 2 and PE 4. By creating a PW between PE1 and
PE 2 (PW1) and a PW between PE 2 and PE 4 (PW2) and then concatenating the two PWs on PE 2, you
can create an intra-domain multi-segment PW between PE 1 and PE 4.
Intra-domain multi-segment PWs can fully unitize existing public tunnels to reduce end-to-end public
tunnels.
Figure 63 Intra-domain multi-segment PW
CE 1
MPLS or IP backbone
PE 2
PW 2
PE 1
Figure 63, there is no public tunnel between PE 1 and PE 4 but there is a pubic tunnel
MPLS or IP backbone
PE 1
Tunnel
PE 3
PE 3
PW
PW 1
PE 2
PW
PE 4
228
PE 4
CE 2
PW 2
CE 2