💡
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

Ethernet LAN Switching

PreviousAAA 802.1x Protocols(Radius & TACACS+)NextVLAN

Last updated 4 years ago

As mentioned earlier, When a receives the frame on it's port it Open the Frame, refer the MAC Table & forward the frame to the relevant port only & not to all the other ports (not to filter). This decision is called "Forward-Versus-Filter" decision. (Note: Switch won't refer the MAC Table if it receives the Broadcast Frame FF:FF:FF:FF:FF:FF. It will simply Broadcast it further).

  • To perform LAN Switching, Switch performs these 3 actions:

    1. Examine the SMAC & make the entry in the MAC Table

    2. Deciding when to forward or not to forward depending on the DMAC Address

    3. To forward only one copy of the frame to avoid creating loop Using logic.

  1. Switch creates multiple copies of the Frame in 3 Scenarios:

    1. If it receives a Broadcast Frame

    2. If it receives a Multicast Frame

    3. If DMAC Address is not known in the MAC Address Table. (unknown-destination uni-

      cast frames)

  2. If sender & receiver are on the same port then Switch will discard the Frame. As Switch switches between the port & not within the ports.

  3. If sender & receiver are on the different ports, Switch will bridge the information on the relevant port only & not to all the other ports.

  4. Switch works exactly as per the rules, it will sense the port before putting the frame on the wire, will check the CRC code & so on. But with the help of the hardware it overcomes the flaw of CSMA/CD that says only one computer can talk at a time & everybody else will listen.

  5. Switch allows simultaneous communications between multiple communicating pairs connected on the different ports.

  6. Every port of Switch has it's own dedicated bandwidth, Hence Switch is a Dedicated bandwidth device.

  7. And Every port of Switch is a member of the Separate Collision domain, hence Switch is a Multiple collision domain device but every port of a Switch is a member of the same broadcast Domain hence Switch is a Single Broadcast domain device.

  8. You can configure IP Address on a PC & a Router but you cannot configure IP Address on a Switch as it is a L2 device. To configure IP Address on a Switch we use SVI (Switched Virtual Interface) (Software Interface) (Interface) which is configured on a VLAN (Virtual Local Area Network) to get an access to the .

Reference:

  • CCNA 200-301 OCG, Volume 1, Pg. 109-114 - Wendell Odom.

  • RST Notes

Switch
STP
CSMA/CD
VLAN
Switch