LAN and Enterprise


This documentation is related to typical LAN techologies found in Enterprise or End Customer networks. This includes IGP, multicasting, switching and Customer Edge systems like NAT or Firewall Security.

  • EIGRP Key Chains: A handy diagram showing the steps necessary to configure EIGRP authentication.


  • NAT Types: Inside and Outside NAT vs. Local and Global NAT is a bit confusing. Use this diagram as a quick reference to keep it straight in your head:


  • IGMPv2 Queries, Reports and Timers: Shows the basics of who sends what queries/reports to who and how often they are sent.


  • IPv6 Router Solicitation/Advertisement Sequence and Address Resolution:  Shows the basics of RS and RA exchanges in IPv6 as well as Address Resolution (the equivalent of ARP in IPv4).


  • OSPF and EIGRP Neighborship Requirements:  Useful mnemonic device to help remember the neighborship requirements for OSPF and EIGRP neighbours. MMANTRAPS.


  • Destination Multicast MAC Address Calculation:  This shows how the destination multicast MAC address is calculated from the destination multicast IPv4 address. It also breaks down how and why there is an overlap of multiple Class D multicast addresses to a single destination MAC.


  • Embedded RP in IPv6 Multicast:  Shows the breakdown of the calculation used to determine the RP address when Embedded RP addressing is used in IPv6 Multicast


  • Etherchannel: This document gives a good cheat-sheet style overview of Etherchannel technology, showing the configuration of both PAgP and LACP.


  • Reading an SNMP MIB: Using mib 2 as an example, this document details how to read and interpret an SNMP MIB that uses the SMIv1 standard.


  • First Hop Redundancy Protocol – Quick Reference Table: A summary table showing FHRP protocols and their characteristics. Handy for comparing the different technologies.


  • Performing a debug on a Junos SRX: A very quick and dirty step-by-step outline of how to perform debugging on a Juno SRX Firewall


  • Type of Service Byte – IP Precedence and DSCP: A summarised overview of the ToS Byte and how it relates to IP Precedence and DSCP. Perfect for anyone studying QoS.


  • OSPF Stub Area Types: A quick reference view of the different OSPF Stub Area types, how they’re configured and what LSAs are flooded where.



  • OSPF LSA Types: A reference sheet for all the OSPF LSA Types supported by Cisco with details of their contents, scope and general usage.