• Best VPN Service

    Top VPNs that Unlock Netflix, provide Secure Torrenting, Strong Encryption, Fast Downloads, DNS Leak Protection, Identity Protection and have Cheap VPN prices.

    read more

    Hyper-V Concepts

    It's time to get familiar with Hyper-V Virtualization, virtual servers, virtual switches, virtual CPUs, virtual deployment infrastructure (VDI) and more.
    Read more

Hot Downloads

Interior Gateway Protocol - IGRP

Posted in Routing Protocols

Introduction

Interior Gateway Routing Protocol (IGRP) is a Cisco proprietary Distance-Vector routing protocol. This means that all your routers must be Cisco routers in order to use IGRP in your network, keep in mind that Windows 2000 now supports it as well because they have bought a licence from Cisco to use the protocol !

Cisco created this routing protocol to overcome the problems associated with RIP.

Open Shortest Path First (OSPF) Routing Protocol

Posted in Routing Protocols

Introduction

Open Shortest Path First (OSPF) is a routing protocol developed for Internet Protocol (IP) networks by the interior gateway protocol (IGP) working group of the Internet Engineering Task Force (IETF). The working group was formed in 1988 to design an IGP based on the shortest path first (SPF) algorithm for use in the Internet. Similar to the Interior Gateway Routing Protocol (IGRP), OSPF was created because in the mid-1980s, the Routing Information Protocol (RIP) was increasingly unable to serve large, heterogeneous internetworks.

OSPF is a classless routing protocol, which means that in its updates, it includes the subnet of each route it knows about, thus, enabling variable-length subnet masks. With variable-length subnet masks, an IP network can be broken into many subnets of various sizes. This provides network administrators with extra network-configuration flexibility.These updates are multicasts at specific addresses (224.0.0.5 and 224.0.0.6).

For more information on OSPF visit our OSPF Routing Protocol section

The diagram below shows us the information that each field of an OSPF packet contains:

ospf-1

Routing Information Protocol - RIP

Posted in Routing Protocols

Introduction

Routing Information Protocol (RIP) is a true Distance-Vector routing protocol. It sends the complete routing table out to all active interfaces every 30 seconds. RIP only uses hop count to determine the best way to a remote network, but it has a maximum allowable hop count of 15, meaning that 16 is deemed unreachable. RIP works well in small networks, but it is inefficient on large networks with slow WAN links or on networks with large number of routers installed.

RIP comes in two different versions. RIP version 1 uses only classful routing, which means that all devices in the network must use the same subnet mask. This is because RIP version 1 does not include the subnet mask when it sends updates. RIP v1 uses broadcasts (255.255.255.255).

Link State Routing Protocols

Posted in Routing Protocols

Introduction

Link State routing protocols do not view networks in terms of adjacent routers and hop counts, but they build a comprehensive view of the overall network which fully describes the all possible routes along with their costs. Using the SPF (Shortest Path First) algorithm, the router creates a "topological database" which is a hierarchy reflecting the network routers it knows about. It then puts it's self on the top of this hierarchy, and has a complete picture from it's own perspective.

Link State protocols, unlike Distance Vector broadcasts, use multicast.

CCENT/CCNA

Cisco Routers

  • SSL WebVPN
  • Securing Routers
  • Policy Based Routing
  • Router on-a-Stick

VPN Security

  • Understand DMVPN
  • GRE/IPSec Configuration
  • Site-to-Site IPSec VPN
  • IPSec Modes

Cisco Help

  • VPN Client Windows 8
  • VPN Client Windows 7
  • CCP Display Problem
  • Cisco Support App.

Windows 2012

  • New Features
  • Licensing
  • Hyper-V / VDI
  • Install Hyper-V

Linux

  • File Permissions
  • Webmin
  • Groups - Users
  • Samba Setup