1*4882a593SmuzhiyunU-Boot has networking support for VLANs (802.1q), and CDP (Cisco 2*4882a593SmuzhiyunDiscovery Protocol). 3*4882a593Smuzhiyun 4*4882a593SmuzhiyunYou control the sending/receiving of VLAN tagged packets with the 5*4882a593Smuzhiyun"vlan" environmental variable. When not present no tagging is 6*4882a593Smuzhiyunperformed. 7*4882a593Smuzhiyun 8*4882a593SmuzhiyunCDP is used mainly to discover your device VLAN(s) when connected to 9*4882a593Smuzhiyuna Cisco switch. 10*4882a593Smuzhiyun 11*4882a593SmuzhiyunNote: In order to enable CDP support a small change is needed in the 12*4882a593Smuzhiyunnetworking driver. You have to enable reception of the 13*4882a593Smuzhiyun01:00:0c:cc:cc:cc MAC address which is a multicast address. 14*4882a593Smuzhiyun 15*4882a593SmuzhiyunVarious defines control CDP; see the README section. 16