💡
Network Fundamentals
  • About This Site
  • Network
  • Medium
  • Types of Network:
  • LAN
  • MAN
  • WAN
  • Internet
  • Types of Internet Connections
  • Cable Connection
  • DSL Connection
  • Internet Standard & Protocols
  • Internet Networking Model
  • SNA Networking Model
  • OSI Networking Model
  • TCP-IP Networking Model
  • TCP-IP Layers
  • Application Layer
  • HTTP (Hyper Text Transfer Protocol)
  • Transport Layer
  • TCP (Transmission Control Protocol)
  • Network Layer
  • IP (Internet Protocol)
  • IPv4:
  • IPv4 Address parts
  • IPv4 Address Classes
  • IPv6:
  • Data-Link Layer
  • Physical Layer
  • An Ethernet
  • A SOHO LAN Network
  • An Enterprise LAN Network
  • Physical Layer Standards
  • Data-Link Layer Standards
  • Transmitting Data over Ethernet UTP
  • Transmitting Data over Fiber Optic Cable (using Hot-Pluggable Transceivers)
  • Cabling Pinouts (Ethernet UTP)
  • Cabling Pinouts (Fiber Optic)
  • Ethernet Standards (UTP)
  • Ethernet Standards (Fiber Optic)
  • LAN Data-Link Layer Protocols
  • Ethernet Addressing (MAC)
  • Types of Networking Devices
  • HUB
  • SWITCH
  • CSMA/CD (Carrier Sense Multiple Access / Collision Detection):
  • Lease-Line WAN
  • WAN Data-Link Layer Protocols
  • HDLC Encapsulating and Re-encapsulating
  • Ethernet WAN (EoMPLS)
  • IP Routing (BIG FLOW)
  • Router
  • Subnetting
  • Binary Rules
  • Binary Method Example 1
  • Binary Method Example 2
  • Binary Method Example 3
  • Subnetting Quick Method Rules
  • Subnetting Quick Method Example 1
  • Subnetting BEST Method Rules
  • Subnetting BEST Method Example 1
  • Subnetting BEST Method Example 2
  • Subnetting BEST Method Example 3a
  • Subnetting BEST Method Example 3b
  • Subnetting BEST Method Example 3c
  • Subnetting BEST Method Example 4
  • Dynamic Routing Protocol
  • DNS (Domain Name System)
  • ARP (Address Resolution Protocol)
  • PING (Packet Internet Groper)
  • Cisco OS (IOS)
  • Memory Types
  • Cisco CLI
  • Console Port:
  • Telnet Access (Teletype network) (P No. 23):
  • SSH (Secure Shell) (P No. 22)
  • Console Cabling
  • CLI Modes
  • Securing User Mode and Privileged Mode
  • Securing User & Privileged Mode For Console Users
  • Securing User & Privileged Mode For Telnet Users
  • Securing User & Privileged Mode For SSH Users
  • AAA (Authentication, Authorization and Accounting) Server
  • AAA 802.1x Protocols(Radius & TACACS+)
  • Ethernet LAN Switching
  • VLAN
  • Configuring VLAN
  • VTP (Vlan Trunking Protocol)
  • Trunk Port
  • Trunking Protocol (802.1Q)
  • DTP (Dynamic Trunking Protocol)
  • Voice VLAN
  • Why STP?
  • What STP Does?
  • How STP works?
  • STP Messages (BPDU)
  • Electing a RB (Root Bridge/Switch)
  • Electing One Root Port (on each Non RB)
  • Elect One/Multiple Designated Ports on each Non RB:
  • Changing the STP Settings:
  • STP (Spanning Tree Protocol)
  • STP Convergence (if something changes/link fails):
  • STP (Spanning Tree Protocol) Versions
  • STP/RSTP States:
  • PortFast
  • BPDU Guard
  • RSTP (Rapid Spanning Tree)
  • Port Roles in RSTP
  • RSTP Port States
  • Ether Channel
  • Switched Virtual Interface
  • Half Duplex
  • Full Duplex
  • Autonegotiation
  • Duplex Mismatch:
  • Verifying Duplex Mismatch
  • Number History
  • 10 to the power of x
  • 2 to the power of x
Powered by GitBook
On this page

BPDU Guard

PreviousPortFastNextRSTP (Rapid Spanning Tree)

Last updated 4 years ago

An Attacker could connect to one of the LAN Switch's Edge port with Low priority & become the RB & can copy Large number of Data Frames or Forward huge traffic in the LAN.

  • Or if mistakenly we connect an inexpensive SW to the Edge port of out LAN Switch which does not use/support /then it may cause a Loop.

  • Solution is BPDU Guard.

  • BPDU Guard disables the port if any BPDU is received on the Port to prevent the Loop & for security.

  • BPDU Guard must be enabled where PortFast is configured (Edge Port) that connects the end devices & not the other Switch.

Reference:

  • CCNA 200-301 OCG, Volume 1, Pg. 236 - Wendell Odom.

  • RST Notes

STP
RSTP
https://vimeo.com/ondemand/ccna200301/397383597?autoplay=1