Suggested Articles:
The IEEE 802.3 SNAP Frame Format
While the original 802.3 specification worked well, the IEEE realized that some upper layer protocols required an Ethertype to work properly. For exa…
ICMP Protocol - Part 7: Time Exceeded Message Ana…
The ICMP - Time Exceeded message is one which is usually created by gateways or routers. In order to fully understand this ICMP message, you must be…
Important Direct Cable Connection Notes
This page was designed to provide some notes on Direct Cable Connection (File-transfer) of Win9x/ME/2000 with LAPLINK (Printer port) Cable or Null-Mo…
Data Encapsulation & Decapsulation in the OSI Mod…
Here we are going to explain in detail how data travels through the OSI model. You must keep in mind that the OSI model is a guideline. It tells the…
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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: 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…
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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…
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…
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…
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…
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…
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 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…
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…
Introduction to Palo Alto Next-Generation Network Fire…
During the past decade, we’ve seen the global IT security market flooded with new network security and firewall security appliances. New vendors emerging…
DHCP Option 82 Message Format, Analysis. DHCP Snooping…
This article provides in-depth analysis of DHCP Option 82 (DHCP Relay Agent) which is one of the +180 DHCP Options available to the DHCP protocol and used…
Renaming Windows 2000 Domain Name
Sometimes renaming a domain is an essential business requirement. There are many situations, such as mergers, change of company name or migration from a t…
8 Critical Features to Have in a VM Backup Solution
Businesses that rely on virtual machines for their day-to-day operations should think twice about securing their infrastructure. Modern use of virtual mac…