Suggested Articles:
Transmission Control Protocol - Part 3: The TCP H…
This article shows the TCP Header and Segment. We explain where the TCP Header and Segment are located in an Ethernet frame and also briefly view the…
The OSI Model: Layer 6 - Presentation Layer
The Presentation Layer gets its name from its purpose: It presents data to the Application layer. It's basically a translator and provides coding and…
Hubs & Repeaters
Network hubs were once the primary method of interconnecting network devices to create a local area network (LAN). Hubs were inexpensive, easy to ins…
TCP Header Anaylsis - Section 2: TCP Sequence & A…
This page will closely examine the Sequence and Acknowledgement numbers. The very purpose of their existence is related directly to the fact that the…
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Netflow Articles:
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…
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: 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 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…
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VLAN Security - Making the Most of VLANs
It's easy to see why virtual LANs have become extremely popular on networks of all sizes. In practical terms, multiple VLANs are pretty much the same as h…
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…
Dynamic VLANs
Dynamic VLANs were introduced to grant the flexibility and complexity(!) that Static VLANs did not provide. Dynamic VLANs are quite rare because of their…
Comparing Traditional Flat & VLAN Networks
Designing and building a network is not a simple job. VLANs are no exception to this rule, in fact they require a more sophisticated approach because of t…
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…
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…
OSPF - Part 6: OSPF LSA Types - Purpose and Function o…
Our previous article explained the purpose of Link State Update (LSU) packets and examined the Link State Advertisement (LSA) information contained within…
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…
Complete Guide: Configuring IPSec VPN between Palo Alt…
This article will show you how to configure an IPSec VPN tunnel between a Palo Alto firewall (all PANOS versions) and Meraki MX security appliance. Our co…
How To Configure Dynamic DNS Server On A Cisco Router
Hosting your own webserver or email server would normaly require a static IP address from your ISP. This ensures that your services are always reachable u…
Installing Security Device Manager (SDM) on a Cisco Ro…
For years now, Cisco has been developing its Security Device Manager (SDM) software. This web-based software is designed to help the less experienced user…
How to Detect Routing Loops and Physical Loops with a…
When working with medium to large scale networks, IT departments are often faced dealing with network loops and broadcast storms that are caused by user e…