The C-NIM-4X is a Next-Generation 1G/10G LAN/WAN module with local Layer 2 switching capabilities on all four ports. This provides a price-effective, low-density 4-port Layer 2 LAN switch with capacity for switching four Small form-Factor Pluggable (SFP)/SFP+ ports at speeds up to 10 Gbps. The two highest-numbered ports can be configured for native Layer 3 operation. Configuring ports for Layer 3 will provide full feature parity with the router’s embedded WAN ports. This module provides high-speed WAN connectivity through four ports supporting serial gigabit media-independent interface (SGMII)/1000BASE-X-based SFP and 10GBASE-R-based SFP+ pluggables. A 100-Mbps optic pluggable connection can also be supported by using the GLC-GE-100FX SFP transceiver. The four 1G/10G WAN ports are connected to the backplane using a single 10-Gbps-capable internal link. When used at maximum capacity, they thus form what is known as an oversubscribed connection of 4 to 1. IEEE 802.1AE MACsec is supported as described in the Product Overview.