
CDP version 1 was introduced in 1994 and was only capable of collecting information about connected devices.  This version is used today for backward compatibility.

Version 2 introduced type length value (TLV) format for frames to make them extendable and flexible.

Links:
https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/cdp/configuration/15-mt/cdp-15-mt-book/nm-cdp-discover.html#GUID-8323D171-09A9-48DE-8BB2-ECD64DAD3D6A

CDP versions messages timers

BGP Update Total Path Attribute Length field

BGP active and passive peers

BGP advertises only the best path by default

BGP advertising a default route

BGP aggregate-address

BGP and route tagging

BGP applying route maps to prefixes

BGP backdoor route

BGP communities

BGP community propagation

BGP community types

BGP configuring authentication on an established BGP session

BGP dmzlink-bw feature

BGP hold timer

BGP how MED attribute is compared

BGP installing a BGP-learned route into the routing table

BGP internal vs external

BGP neighbor activate command

BGP neighbor-group

BGP paths indicated in the show ip bgp command

BGP peer groups

BGP peer templates

BGP peering redundancy using loopbacks

BGP regular expressions - use of 4-Byte ASNs

BGP regular expressions - use of backslash for confederations

BGP risk of using the as-override feature

BGP route dampening penalty half-life

BGP route refresh capability annoucement

BGP soft reconfiguration on Cisco ASA

BGP soft reconfiguration

BGP sub autonomous system

BGP table status codes

BGP traffic engineering

BGP using next-hop-self with a route reflector

BGP weight attribute default value

BGP when to use next-hop-self

BGP which address is used as the next hop

BGP why do we need an IGP for BGP to work

BGP why route dampening is obsolete

Best practice - concerning undebug all

Best practice - prevent connectivity loss of remote device

Bidirectional Forwarding Detection (BFD)

Broadcast MAC address

Broadcast traffic

CBC-MAC

CBWFQ and shaping

CCNP SCOR exam topics

CDP - best practices

CEF - Operation within a chassis switch

CEF Load Balancing Algorithm

CISCO ASA IKEv2 hub and spoke

CLI Filtering show commands

CPM - Cisco Performance Monitor

CPM - Collect keyword

CPM - match and collect keywords

Career study advice

Carrier-Grade NAT

Certificate Authority Structure

Certification Cisco exam topics blueprint

Certifications - Continuing Education Credits

Certifications - online remote proctored exams

Cisco ASA Active-Active

Cisco ASA Active-Standby failover preemption

Cisco ASA Active-Standby

Cisco ASA HTTPS server

Cisco ASA show listening ports

Cisco Anyconnect SSL WebVPN

Cisco CCDE practice lab example

Cisco CCDE technology

Cisco CCDE

Cisco Context-Based Access Control (CBAC)

Cisco Discovery Protocol (CDP)

Cisco Feature Navigator

Cisco IOS Auth Manager

Cisco IOS Firewall feature set

Cisco IOS Order of Operation

Cisco IOS show listening ports

Cisco IOS test aaa command

Cisco Identity Services Engine (ISE)

Cisco Network Data Platform (NDP)

Cisco Pagent Router

Cisco QoS HCF shaper and bandwidth inheritance

Cisco Quantum Flow Processor

Cisco SD-Access home lab

Cisco SD-WAN IPSec encapsulation on tunnel interface of vBond

Cisco SD-WAN Troubleshooting

Cisco SD-WAN backup vManage NMS configuration database

Cisco SD-WAN controller troubleshooting

Cisco SD-WAN export configs and files

Cisco SD-WAN export with python

Cisco SD-WAN lab options

Cisco SD-WAN rebranding

Cisco SD-WAN request upload

Cisco SD-WAN save command

Cisco SD-WAN scp command

Cisco SD-WAN vEdge Troubleshooting

Cisco SD-WAN vManage tail log

Cisco SD-WAN verify connectivity in Service VPN