MAC address format convert with excel

  Format : 001122334455 -> 00:11:22:33:44:55   From MS Excel, 1. Put a raw MAC address : ex) 001122334455 on A1 2. Copy and paste…

Continue Reading...

Ethernet frame and MTU

Ethernet Frame Sizes Standard Ethernet Frame (without 802.1Q): Total Size: 1518 Bytes Breakdown: Destination MAC: 6 Bytes Source MAC: 6 Bytes Type: 2 Bytes Data:…

Continue Reading...

How to find network card vendor by OUI lookup/MAC address

What is an OUI? The Organizationally Unique Identifier (OUI) is the first 24 bits of a MAC address (out of a total of 48 bits)….

Continue Reading...

How to capture traffic using VACL

How to Capture Network Traffic Using VACL Introduction to VACL (VLAN Access Control List) VLAN Access Control Lists (VACLs) are powerful tools used to capture…

Continue Reading...

How to configure IRB(Integrated Routing and Bridging)

Tweet [ Backgroud ] PC1 is connected to Fa0/0(no IP address, bridge) of Router = IP 10.10.10.1/24 PC2 is connected to Fa0/1(no IP address, bridge)…

Continue Reading...

Ethernet speed and duplex configuration

Ethernet Speed and Duplex Configuration Understanding Speed and Duplex Settings In networking, the speed and duplex settings of Ethernet interfaces are crucial for optimal performance….

Continue Reading...

What is UDLD protocol ?

Understanding the UDLD Protocol What is UDLD? The Unidirectional Link Detection (UDLD) protocol is a Layer 2 (L2) protocol designed by Cisco to detect unidirectional…

Continue Reading...

Ethernet Cable Guide

Tweet UTP(Unshielded Twisted Pair) Cable Cat3, Cat5, Cat5e, Cat6 Weakness on Electromagnetic Interference(EMI) Installation Guide – Avoid direct sunshine and humidity – Enough distance from device…

Continue Reading...

How to read Cisco FastEthernet Interface status

Tweet Sometimes, by looking over some basic or fundamental information during troubleshooting, we got wrong path and wasted hack of time. If you carefully reviewed…

Continue Reading...

Many “runts” are being detect on Ethernet interface ?

Tweet Question: Many “runts” are being detect on Ethernet interface ?   Answer: It could be duplex mismatching issue. First of call, Runts: These are…

Continue Reading...

What is Alignment Errors ?

What Are Alignment Errors? Understanding Alignment Errors Alignment errors occur when frames received do not end on an even number of octets and have a…

Continue Reading...

What is standard Ethernet frame size and MTU ?

Understanding Standard Ethernet Frame Size and MTU What is the Standard Ethernet Frame Size? The Ethernet frame size consists of several components, excluding the preamble:…

Continue Reading...