Hello, everyone!
This time, I'm going to share the E-LINE service model(Traditional Ethernet services, not packet services) with you. I hope you like it!
1. Point-to-Point Transparently Transmitted E-Line Services
In E-Line services, point-to-point transparent transmission is the basic transmission mode of E-Line services. It does not need to share service bandwidth or isolate or differentiate the transmitted services. so, it transparently transmits all Ethernet services between two service access points.
Model 1: Ethernet services Service1 and Service2 that do not carry or carry an unknown VLAN ID are accessed to NE1 through Port1 and Port2 respectively. Port1 and Port2 transparently transmit Service1 and Service2 to Port3 and Port4 respectively. Ports 3 and 4 transmit services 1 and 2 to NE2.
Model 2: Ethernet services Service1 and Service2 that do not carry or carry an unknown VLAN ID are accessed to NE1 through Port1 and Port2 respectively. Port1 and Port2 process all the packets passing through the port according to the TAG attributes and send Service1 and Service2 to Port3 and Port4 respectively. Port 3 and Port 4 process all packets passing through the port according to the TAG attributes, and then transmit Service 1 and Service 2 to NE2.
2. VLAN-based E-Line service model
In E-Line services, VLANs are used to isolate E-Line services. In this way, multiple E-Line services share a physical channel.
Ethernet services Service1 and Service2 with different VLAN IDs are connected to NE1 through Port1 and Port2 respectively. Port3 shares the transmission channel and isolates the services through VLANs.
On NE1, Port1 and Port2 process all the packets that pass through the port according to the TAG attributes and transmit Service1 and Service2 to Port3. Port 3 processes all packets on the outbound interface according to the TAG attribute, and then transmits Service1 and Service2 to NE2. Service1 and Service2 carry different VLAN IDs. Therefore, Port3 can be shared for transmission.
3. QinQ-based E-Line service model
In an E-Line service, an S-VLAN tag is added to packets for service isolation. In this way, multiple E-Line services share a physical channel.
Service model 1: Ethernet services Service1 and Service2 include both tagged frames and untagged frames. Service1 and Service2 are connected to NE1 through Port1 and Port2 respectively. Port1 and Port2 add different S-VLANs to the Ethernet frames of Service1 and Service2 respectively, and then transmit the frames to Port3. Port 3 transmits service 1 and service 2 to NE2.
Service model 2: Ethernet services 1 and 2 carry unknown C-VLANs. Service 1 and service 2 access NE 1 through port 1 and port 2 respectively. Port 1 and port 2 add different S-VLANs to the Ethernet frames of service 1 and service 2. Then it is transmitted to Port3. Port 3 then transmits service 1 and service 2 to NE2.
Service model 3: Ethernet services Service1 and Service2 carry different C-VLANs. Service1 and Service2 are connected to NE1 through Port1 and Port2 respectively. Port1 and Port2 add different S-VLANs to the Ethernet frames of Service1 and Service2 respectively and then transmit the frames to Port3. Port 3 transmits Service1 and Service2 to NE2.
Service model 4: Ethernet services Service1 and Service2 carry the same S-VLAN. Service1 and Service2 are connected to NE1 through Port1 and Port2 respectively. Port1 and Port2 convert the S-VLANs carried by Service1 and Service2 into different values and then transmit the S-VLANs to Port3. Port 3 transmits Service1 and Service2 to NE2.
More: ELAN service model
Thank you!
