[j-nsp] L2Circuits vs L2 VPN

[Marlon Duksa]

Can someone explain what is the difference between L2 Circuits and L2 VPNs
besides the obvious (which is signaling LDP vs BGP).

Junos 9.1 doc states this in the VPN conf guide, page 509.

"A Layer 2 circuit is similar to a circuit cross-connect (CCC), except
that multiple Layer 2 circuits can be transported over a single
label-switched path
(LSP) tunnel between two provider edge (PE) routers. In contrast, each CCC
requires
a dedicated LSP."

What does it mean the each CCC requires a dedicated LSP? If I build a
transport tunnel using LDP, then all L2 VPN instances between two PEs will
use the same tunnel, no matter whether ai use CCC or not.

Thanks,
Marlon