The 4-port DS3/E3 Adapter card has two versions. Both versions have the same functionality; version 2 of the adapter card is a replacement for version 1.
The 4-port DS3/E3 Adapter card has four TDM DS3/E3 ports. The port type must be configured to be either DS3 or E3. Each DS3 port can be clear channel or channelized down to DS0 (64 kb/s). E3 ports can be clear channel only. Once the first port type has been configured, all other ports on the same 4-port DS3/E3 Adapter card must be set to the same type.
To change between types, the ports must first be deleted. DS3 ports provide B3ZS (bipolar with three-zero substitution) zero code suppression and E3 ports provide HDB3 (high density bipolar of order 3) zero code suppression. B3ZS and HDB3 zero code suppression are line coding techniques.
Channelization is supported down to the DS0 level (for DS3 ports only). To change port types, all ports must first be shut down. The ports can be configured for DS1 (T1) or E1 operation. All ports on the card must be either T1 or E1; 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.