In our case we use the CDP because it is enabled by default on all our equipment (the LLDP integration is in another post). CDP (Cisco Discovery Protocol) allows Cisco devices to be identified among them. For example, this system is used to find the IP address or port that is connected to another Cisco equipment. Broadly, this is a proprietary protocol that handles to send multicast information (every 60 seconds) to each device connected to accelerate identification.įor people who don’t have a Cisco network, there is another standardized protocol named LLDP offering more or less the same services.