The following lists encapsulation service options on Ethernet ports:
null
Null supports a single service on the port. For example, where a single customer with a single service customer edge (CE) device is attached to the port. The encapsulation ID is always 0 (zero).
dot1q
Dot1q supports multiple services for one customer or services for multiple customers (Figure: 7750 SR/7950 XRS service access point (SAP) and Figure: 7750 SR/7950 XRS and 7450 ESS multiple SAPs on a single port/channel). For example, the port is connected to a multi-tenant unit (MTU) device with multiple downstream customers. The encapsulation ID used to distinguish an individual service is the VLAN ID in the IEEE 802.1Q header.
QinQ
The QinQ encapsulation type adds a IEEE 802.1Q tag to the 802.1Q tagged packets entering the network to expand the VLAN space by tagging tagged packets, producing a double tagged frame.
There are several 7750 SR encapsulation service options on SONET/SDH channels:
Internet Protocol Control Protocol (IPCP)
IPCP supports a single IP service on a SONET/SDH port or a single service per channel (if the interface is channelized). This is typically used for router interconnection using point-to-point protocol (PPP).
Bridging Control Protocol (BCP-null)
BCP-null supports a single service on the SONET/SDH port or a single service per channel (if the interface is channelized). This is used for bridging a single service between two devices using PPP over SONET/SDH. The encapsulation ID is always 0 (zero).
Bridging Control Protocol (BCP-dot1q)
BCP-dot1q supports multiple services on the SONET/SDH port/channel. This encapsulation type is used for bridging multiple services between two devices using PPP over SONET/SDH. The encapsulation ID used to distinguish services is the VLAN ID in the IEEE 802.1Q header in the BCP-encapsulated frame.
There are several 7450 ESS encapsulation service options on SONET/SDH channels:
Internet Protocol Control Protocol (IPCP)
IPCP supports a single IP service on a SONET/SDH port. This is typically used for router interconnection using point-to-point protocol (PPP).
Bridging Control Protocol (BCP-null)
BCP-null supports a single service on the SONET/SDH port. This is used for bridging a single service between two devices using PPP over SONET/SDH. The encapsulation ID is always 0 (zero).
Bridging Control Protocol (BCP-dot1q)
BCP-dot1q supports multiple services on the SONET/SDH port. This encapsulation type is used for bridging multiple services between two devices using PPP over SONET/SDH. The encapsulation ID used to distinguish services is the VLAN ID in the IEEE 802.1Q header in the BCP-encapsulated frame.
