Suggested Articles:
ICMP Protocol - Part 6: Redirect Messages
The ICMP - Redirect Message is always sent from a gateway to the host and the example below will illustrate when this is used.
Putting it simply (be…
The OSI Model: Layer 3 - Network Layer
The Network layer is responsible for routing through an internetwork and for networking addressing. This means that the Network layer is responsible…
802.3 Fast Ethernet (100 Mbit/Sec) Model
Here we see a logical drawing of the Fast Ethernet Data Link Layer sublayers. Data is passed down from the upper layers (such as TCP/IP or Novell Net…
The OSI Model: Layer 5 - Session Layer
The Session layer is responsible for setting up, managing and then tearing down sessions between Presentation layer entities. The Session layer also…
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Netflow Articles:
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…
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…
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…
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Static VLANs
VLANs are usually created by the network administrator, assigning each port of every switch to a VLAN. Depending on the network infrastructure and securit…
VLANs - Access & Trunk Links
If you've read our previous article The VLAN Concept - Introduction to VLANs then you should feel comfortable with terms such as 'VLAN', 'Stati…
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…
VLANs - IEEE 802.1q Trunk Link Protocol Analysis
While the VLAN Tagging article briefly covered the IEEE 802.1q protocol this article will continue building upon it by further analyzing the IEEE 802.1q T…
Interior Gateway Protocol - IGRP
IGRP (Interior Gateway Routing Protocol) is a Cisco proprietary distance-vector routing protocol used in enterprise networks to exchange routing informati…
OSPF - Part 1: Introduction, OSPF Packet Structure, OS…
Open Shortest Path First (OSPF) is a popular routing protocol developed for Internet Protocol (IP) networks by the Interior Gateway Protocol (IGP) working…
Routing Information Protocol - RIP
Routing Information Protocol (RIP) is a distance-vector routing protocol that is commonly used in small to medium-sized networks. It is one of the o…
OSPF - Part 5: Analysis of OSPF Link State Update (LSU…
This article explains how OSPF uses Link State Advertisement (LSA) to exchange information about the network topology between routers. When a router recei…