Suggested Articles:
Ethernet Protocol, CSMA/CD, Collisions
Ethernet Troubleshooting - Physical Frame Corrupt…
When troubleshooting your Ethernet network, the first thing to look for is physical frame corruption. In this essay, we will discuss the different ca…
Network Cabling
100Base-(T) TX/T4/FX - Ethernet
The 100Base-TX (sometimes referred to 100Base-T) cable was until 2010 perhaps the most popular cable around since it has actually replaced the older…
TCP - UDP Protocol Analysis
Transmission Control Protocol - Part 2: Quick Ove…
As previously mentioned on a number of occasions, TCP is one of the two protocols that lives at the Transport layer and is used to carry data from on…
TCP - UDP Protocol Analysis
TCP Header Anaylsis - Section 4: TCP Flag Options
As we have seen in the previous pages, some TCP segments carry data while others are simple acknowledgements for previously received data. The popula…
Featured Subcategories:
Netflow Articles:
Complete Guide to Netflow: How Netflow & its Comp…
This article will cover the basics of Netflow, including its use cases, Netflow supported devices, Netflow history, and variants. We’ll also dive int…
Netflow vs SNMP. Two Different Approaches to Netw…
SNMP (Simple Network Management Protocol) and Netflow are both popular protocols with admins, prized for their ability to give visibility over the ne…
NetFlow Analyzer: Free Download, Step-by-Step Ins…
In our previous article we explained how a Netflow Analyzer can help you gain visibility into your user traffic, application traffic and data flows w…
Netflow: Monitor Bandwidth & Network Utilization…
Monitoring network traffic & bandwidth usage via Netflow is mandatory for any type and size network. Gaining visibility into user traffic, applic…
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VLAN Networks
VTP Protocol - In-Depth Analysis
The previous article introduced the VTP protocol, we examined how it can be used within a network, to help manage VLANs and ease the administrative overhe…
VLAN Networks
VTP Pruning
VTP (VLAN Trunking Protocol) pruning is a feature that is used in Cisco switches to reduce unnecessary traffic in VLAN (Virtual Local Area Network) trunks…
VLAN Networks
VLAN Tagging - Understanding VLANs Ethernet Frames
We mentioned that Trunk Links are designed to pass frames (packets) from all VLANs, allowing us to connect multiple switches together and independently co…
VLAN Networks
VLAN InterSwitch Link (ISL) Protocol Analysis
Deciding whether to use ISL or IEEE 802.1q to power your trunk links can be quite confusing if you cannot identify the advantages and disadvantages of eac…
Routing
Enhanced Interior Gateway Routing Protocol - EIGRP
Enhanced Interior Gateway Routing Protocol (EIGRP), similar to IGRP, is a Cisco proprietary routing protocol that is used to exchange routing information…
Routing
OSPF - Part 3: OSPF Adjacency & Neighbor Forming Proce…
This is the thrid article of our 6-part OSPF series (see below) that describes how OSPF routers perform neighbor relationship and adjacency. We’ll examine…
Routing
Distance Vector Routing Protocols
Distance Vector routing protocols use frequent broadcasts (255.255.255.255 or FF:FF:FF:FF) of their entire routing table every 30 sec. on all their interf…
Routing
Introduction to Routing Protocols
Distance Vector, Link State RIP, IGRP, EIGRP, OSPF
Routing protocols were created for routers. These protocols have been designed to allow the exchange…
SASE & SD-WAN Networks
Understanding Secure Access Service Edge (SASE) and ho…
Software Defined Wide Area Networking (SD-WAN) is changing the way that businesses connect to the cloud. With SD-WAN, organizations can move away from clo…
Cisco Routers
Configuring Site to Site IPSec VPN Tunnel Between Cisc…
Site-to-Site IPSec VPN Tunnels are used to allow the secure transmission of data, voice and video between two sites (e.g offices or branches). The VPN tun…
Cisco Routers
How to Restrict Cisco IOS Router VPN Client to Layer-4…
In our article Cisco VPN Client Configuration - Setup for IOS Router we explained how to setup up a Cisco IOS router to support Cisco IPSec VPN clie…
SASE & SD-WAN Networks
How To Secure Your SD-WAN. Comparing DIY, Managed SD-W…
With so much enterprise network traffic now destined for the cloud, backhauling traffic across an expensive MPLS connection to a data center to apply secu…







