The 4-port OC3/STM1 / 1-port OC12/STM4 Adapter card can be configured to be in 4-port OC3/STM1 mode or 1-port OC12/STM4 mode (using the mda-mode command).
When the 4-port OC3/STM1 / 1-port OC12/STM4 Adapter card is configured in 4-port OC3/STM1 mode, four SFP ports are available for optical and electrical SFP transceivers. In this mode, the card supports OC3 SONET or STM1 SDH transmission.
When the 4-port OC3/STM1 / 1-port OC12/STM4 Adapter card is configured in 4-port OC3/STM1 mode, channelization is supported down to the DS1 level. To change port types, all ports must first be shut down. The ports can be configured for DS1 (T1) or E1 channelization in access mode, or PPP/MLPPP or POS in network mode. All ports on the card must be either SONET or SDH; there cannot be a mix of the two types. When the first port is configured on a card, all other ports on the card must be set to the same type. Switching between port types causes the adapter card to reset.
When the 4-port OC3/STM1 / 1-port OC12/STM4 Adapter card is configured in 1-port OC12/STM4 mode, SFP port 1 is available for optical SFP transceivers. Ports 2 through 4 are not available. In this mode, the card supports OC12 SONET and STM4 SDH transmission. The 1-port OC12/STM4 mode is designed for use in situations where greater bandwidth is required on a single port.