The final component that is required to set up a functional CS1000E System is the Layer 2 switch. This provides data connectivity between the components of the system, including connectivity to IP sets.
A layer 2 switch transmits data packets directly to the targeted device only, rather than broadcasting them to every device on the network (like a hub would do). This prevents collisions and packet loss on the data network. Nortel recommends the use of a Baystack 460 switch with Power over Ethernet (for installations that use PoE), or the Baystack 470-24T switch.
Any third party layer 2 switch can be used with the CS1000 system, as long as it supports VLAN tagging and QoS. A switch that does not support QoS is not suitable for VoIP applications.
For a Power over Ethernet scenario each IP device requires a device that will split the CAT5 cable to add a power connection. PoE is useful in creating a system that will function in the event of a power failure without the use of a UPS at each station.