all ip addresses of
the interfaces on the router enabled are filled in the hello packet of
the cdp protocol ,otherwise the odr protocol can't run normally.
i think so !
Hi,
CDP is a media and protocol independent protocol that runs on all Cisco-manufactured equipment including routers, bridges, access and communication servers, and switches. Using CDP, you can view information about all the Cisco devices directly attached to the switch. In addition, CDP detects native VLAN and port duplex mismatches.
Protocol-Hello-Allows other protocols to piggyback their Hello packets onto Cisco Discovery Protocol.If you sniff the cdp apcket you can see protocol hello in cdp packet which has the following field in the frame
VLAN Trunking Protocol (VTP) management domain-Names the management domain
Native VLAN-Indicates the number of the native VLAN
Full or half duplex-Indicates if the interface is operating in half or full duplex
Appliance VLAN-Indicates the voice VLAN
Trigger-Offers ability to cause the remote end to immediately send a Cisco Discovery Protocol packet
Power-Adds capability to negotiate power
Extended trust and class of service (CoS)-Offers ability to specify whether the PC port of the phone is trusted and if not, what to mark the Layer 2 packet CoS bits coming in from the PC port.
Sysname-Indicates fully qualified domain name (FQDN) of the device per RFC 1907
sysObjectID-Gives object identifier (OID) per RFC 1907
Management address-Indicates IP addresses for which the device accepts Simple Network Management Protocol (SNMP) messages
Physical location-Gives a string representing the physical location of the devices
External port ID-Identifies the physical fiber
Power requested-Specifies how much power is being requested
Power available-Specifies how much power is available
Port unidirectional mode-Specifies that traffic on this port is one way only
Hope that clear out your query !!
Ganesh.H
