In terms of performance, DSFP modules are capable of handling up to 28 Gbps per electrical lane using Non-Return to Zero (NRZ) signaling, and they double their data rate to 56 Gbps per lane when employing the more complex Pulse Amplitude Modulation 4-level (PAM4) signaling. In today's global market, servers typically connect at speeds of 10 Gigabit Ethernet or 25 Gigabit Ethernet, which are standard for access rates. The QSFP28 integrates 4 transmit and 4 receiver channels. The number 28 means each lane carries up to 28G data rate. All interface speeds, from 1G to 400GE have connectivity options that include Direct Attach copper Cables (DACs), Active Optical Cables (AOCs), multi-mode fiber and single-mode fiber transceivers. SFP stands for Small Form-factor Pluggable, a small module. Introduced in 2001 to replace the larger GBIC, SFP is also known as Mini-GBIC.
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