 | Copyright © 2008, Juniper Networks, Inc. All rights reserved. Trademark Notice. | |
This section describes ATM-to-Ethernet interworking:
ATM-to-Ethernet interworking is supported on M320, M120, and T-series routers.
The ATM-to-Ethernet interworking feature is useful where ATM2 interfaces are used to terminate ATM DSLAM traffic. The ATM traffic can be forwarded with encapsulation type ccc (circuit cross-connect) to a local or remote Gigabit Ethernet IQ2 or 10-Gigabit Ethernet IQ2 interface or label-switched path (LSP). The ATM VPI and VCI are converted to stacked VLAN inner and outer VLAN tags.
These ATM-to-Ethernet interworking circuits can be mapped to individual logical interfaces configured on an ATM2 IQ interface and Gigabit Ethernet IQ2 or 10-Gigabit Ethernet IQ2 physical interface.
The ATM-to-Ethernet interworking cross-connect essentially provides Layer 2 switching, and statistics are reported at the logical interface level.
During conversion from ATM to Ethernet, the least significant 12 bits of the ATM cell VCI are copied to the Ethernet frame inner VLAN tag. Cells received on an ATM logical interface configured with encapsulation type vlan-vci-ccc and falling within the configured VCI range are reassembled into packets and forwarded to a designated Ethernet logical interface that is configured with encapsulation type vlan-vci-ccc.
During conversion from Ethernet to ATM, the Ethernet frame inner VLAN tags that fall within the configured range, are copied to the least significant 12 bits of the ATM cell VCI. The ATM logical interface uses its configured VPI when segmenting the Ethernet packets into cells.
| Copyright © 2008, Juniper Networks, Inc. All rights reserved. Trademark Notice. | |