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USB Direct Cable Connection, USB Versions, Specif…
Today, Serial and Parallel Direct Cable Connections are considered obsolete methods of transferring data between computers. The fact is that even USB…
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The 'ICMP Destination unreachable' message is quite interesting, because it doesn't actually contain one message, but infact six! This means that the…
Troubleshooting techniques for Fast Ethernet
This page will primarily discuss problems unique to Fast Ethernet.
The Collision Domain
Incompatible Ethernet Jabber
Auto-negotiation Priorities…
Transmission Control Protocol - Part 4: In-Depth…
This article is an introduction to the 7-page TCP Header analysis section that follows. We briefly view each section of the TCP Header and then move…
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Netflow Articles:
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 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: 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…
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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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…
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…
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…
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…
Routed Protocols
We all understand that TCP/IP, IPX-SPX are protocols which are used in a Local Area Network (LAN) so computers can communicate between with each other and…
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…
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…