Actually all are the same thing. VPWS stands for virtual private wire service , VLL stands for virtual leased line and EoMPLS stands for Ethernet over MPLS. MPLS Technologies and Design are explained in great detail in my Instructor Led CCDE and Self Paced CCDE course. All are MPLS Layer 2 VPN service and terms are used to define point to point layer 2 circuit.
In this post I will not mention about design best practices , deployment options or scenarios but will keep it simple and only explain the definitions. For MPLS Layer 2 VPN, you can even hear ATOM from Cisco engineers. ATOM stands for Any Transport over MPLS. But it is weird though. MPLS stands for Multi Protocol Label Switching which mean you can carry any protocol through MPLS.
So ATOM is just another version of saying ‘ MPLS ‘. There are different standard bodies probably you heard IETF , IEEE , ITU , MEF (Metro Ethernet Forum) and so on. VPWS is an IETF term. MEF also defined MPLS Layer 2 VPN point to point service and they call it E-Line. Essentially all are same thing. They are the most common MPLS Layer 2 VPN application.
In this post I just covered the definition and the different alternative keywords for VPWS. You can check from the right sidebar many MPLS related posts. To have a great understanding of SP Networks, you can check my new published “Service Provider Networks Design and Perspective” Book. It covers the SP network Technologies with also explaining in detail a factious SP network.