Cisco Hands On Training Podcast

Episodes

1. 41

   IPv6 RIPng dynamic routing

   The linked video demonstrates RIPng, our first dynamic routing protocol for IPv6. This is a simple but inefficient routing protocol. The metric is based on number of router hops, with no provision for differentiating between links with drastically different bandwidth (a frame-relay hop has the…

   more
   Mar 14, 2010
2. 40

   IPv6 Static Routing

   In this hands-on exercise, we configure IPv6 addresses on 3 routers in a triangle. Then we configure IPv6 static routes to allow the 6 IPv6 subnets (3 loopback, 3 P2P links) to be accessible on all 3 routers. Static routes are easy to understand. At first glance they appear simple. You just...

   Nov 2, 2009
3. 39

   The need for QOS versus Net Neutrality

   In 2003, I made a VOIP call from home while downloading a large email attachment. The DSL line saturated and my audio quality became horrible while VOIP packets (and email packets) were being dropped. Doubling the bandwidth to my home would not have solved this problem. The email download would...

   Sep 27, 2009
4. 38

   IPv6 theory

   The linked video introduces IPv6 theory. IPv6 is the 128-bit address replacement for IPv4. The Internet is expected to run out of it's 4-billion IPv4 addresses in 2012. IPv6 will replace IPv4 at the network-layer of the OSI stack. By replacing one layer in the stack, most applications and most...

   Sep 20, 2009
5. 37

   IOS Version Selection Tactics

   The linked video provides guidance for optimal IOS version selection. The large number of IOS versions makes choosing the best version for your router or switch difficult. You must pick the most reliable version which includes the features you need. Different IOS "packages" have different…

   more
   May 31, 2009
6. 36

   IOS Access Control Lists

   In this video demonstration, we show an example of writing IOS Access Control Lists (ACL's) on a home router. We use the revision control system (RCS) to maintain the master ACL file and push the ACL's to the router via TFTP. This is similar to many production networks, where maintaing comments…

   more
   Mar 24, 2009
7. 35

   IOS DHCP and NAT

   IOS routers can act as DHCP clients and DHCP servers. They can also function as Network Address Translation (NAT) devices. In this video we show a demonstration using a 2621 as a DHCP client, server, and NAT translation device for my home network. It's important to understand that most IOS…

   more
   Mar 23, 2009
8. 34

   Hot Standby Router Protocol

   In this episode we show a video demonstration of the hot standby router protocol. This is a Cisco proprietary redundancy protocol. The purpose is to allow two routers to share one virtual IP address on an access subnet/vlan. Hosts on the subnet can use the virtual IP for their default route. This...

   Mar 22, 2009
9. 33

   Rapid Spanning Tree 802.1w

   This video demonstrates layer-2 convergence in less than 2 seconds thanks to rapid spanning-tree. Rapid per-vlan spanning-tree is configured with "spanning-tree mode rapid-pvst". The rapid spanning tree protocol, 802.1w, is the answer to the slow convergence time of the historic 802.1d...

   Mar 8, 2009
10. 32

    Etherchannels and the port aggregation protocol

    When you have two different links between the same two switches, normally spanning tree will forward on one and block on the other. This means half of your bandwidth is sitting idle. An etherchannel is a way to bind two links into one logical link with twice the bandwidth. In addition to…

    more
    Mar 3, 2009
11. 31

    VTP Vlan Trunking Protocol

    VTP is the VLAN trunking protocol. It's used to disseminate uniform vlan information between switches over 802.1q or ISL trunks. It can also "prune" vlans, dynamically removing unneeded VLANs from trunks. This decreases unneeded frame flooding. VTP can eliminate outages thanks to the uniform VLAN...

    Mar 1, 2009
12. 30

    802.1q and ISL trunks

    Switches can have multiple vlans. When we connect switches together we use 802.1q trunks (or older ISL trunks) to run multiple vlans over one physical link. With either trunking protocol, a tag is added to the ethernet frame with the vlan information. ISL is an older Cisco-proprietary trunking...

    Feb 24, 2009
13. 29

    Intermediate spanning tree

    We cover intermediate spanning tree concepts. The importance of specifying your root bridge and backup root bridge with spanning-tree priority. Using portfast to allow host ports to start forwarding without waiting for 30 seconds. Using bpduguard to disable portfast-enabled ports where someone...

    Feb 23, 2009
14. 28

    VLANs and spanning tree

    VLANs are a feature of ethernet switches which makes them act like multiple "virtual switches". Each VLAN is a separate broadcast domain and could be configured with a separate subnet. That way could could have separate subnets for separate purposes (IT, accounting, network management) on one...

    Jan 31, 2009
15. 27

    How ARP and Ethernet Work

    So far we've talked about how IPv4 encodes data into a packet, and how routers learn which direction to forward those IPv4 packets based on the destination IP address and the route table. But in the end, routers and hosts need to encode the IPv4 packet onto a physical medium. Examples of physical...

    Jan 25, 2009
16. 26

    BGP route selection with MEDs

    In BGP, MED stands for Multi Exit Discriminator. It is a well-known optional attribute which allows one autonomous system to inject it's IGP route metrics into its BGP advertisements to another BGP autonomous system. This allows the second autonomous system to make intelligent routing decisions...

    May 29, 2008
17. 25

    BGP route filtering

    We filter BGP routes in 4 different ways.

    Apr 11, 2008
18. 24

    eBGP and iBGP

    We put together what we learned about eBGP, iBGP, and OSPF.

    Mar 22, 2008
19. 23

    iBGP

    An iBGP example with 1 autonomous system with 3 routers.

    Mar 20, 2008
20. 22

    eBGP

    An eBGP example with 3 autonomous systems with 1 router each.

    Mar 19, 2008
21. 21

    Introduction to BGP theory

    An introduction to BGP theory.

    Mar 15, 2008
22. 20

    OSPF route filtering and area border routers

    OSPF routes should be filtered or summarized at area border routers.

    Oct 21, 2007
23. 19

    OSPF distribute-list problems

    OSPF's fundamental design is that all routers in an area have the same exact view of the network topology. This is fundamentally incompatible with filtering routes within an area. As a result OSPF distribute lists do not have the same effect as RIP distribute lists. In fact, using…

    more
    Oct 7, 2007
24. 18

    Totally stubby and not-so-stubby OSPF areas

    OSPF totally stubby areas and not-so-stubby areas are ways to improve OSPF scalability. But they can be very confusing.

    Sep 30, 2007
25. 17

    OSPF stub areas and neighbor synchronization

    We cover OSPF stub areas and neighbor synchronization.

    Sep 23, 2007
26. 16

    OSPF Redistribution

    We redistribute from RIPv2 into OSPF and introduce autonomous system boundry summary LSAs and external summary LSAs.

    Jul 31, 2007
27. 15

    OSPF Areas and Network Summary LSA's

    We introduce multiple OSPF areas and network summary LSA's.

    Jul 16, 2007
28. 14

    Introduction to OSPF

    We show a single area OSPF network and go into router and network link state advertisements (LSA's) in detail.

    Jul 1, 2007
29. 13

    Shortest Path First Algorithm

    A brief tutorial on Dijkstra's Shortest Path First Algorithm. This algorithm is used by most link state routing protocols, including OSPF and IS-IS.

    Jun 4, 2007
30. 12

    RIPv2

    RIP version 2 includes subnet information in the route advertisement. It also improves efficiency by multicasting to RIPv2 routers instead of broadcasting to all hosts.

    Sep 22, 2006
31. 11

    Migrating from RIPv1 to IGRP via route redistribution

    If you run two different routing protocols in two different parts of your network, you need to redistribute routes between the two routing protocols. This session is an introduction to route redistribution by example. In production you must be cautious about route redistribution because the route...

    Jul 25, 2006
32. 10

    Migrating from RIPv1 to IGRP via "ships in the night" routing

    "Ships in the night" routing refers to two routing protocols which do not interact with each other. We can migrate from one routing protocol to a more believable one by simply turning on the new protocol then turning off the old protocol. Bug be careful to turn the new protocol on in the entire...

    Jul 10, 2006
33. 9

    IGRP: Interior Gateway Routing Protocol

    IGRP is a Cisco-proprietary routing protocol. It is a classful distance vector protocol with a metric based on bandwidth and delay. This is superior to RIP, whose metric is based on hop-count. IGRP's classfulness makes it a bad choice for new deployments, but its advanced metric is worth study.

    Jun 29, 2006
34. 8

    RIPv1 distribute lists and offset-lists

    RIP distribute lists deny specific route advertisements. RIP offset-lists increase the metric (hopcount) for specific route advertisements.

    Jun 21, 2006
35. 7

    Problems with RIP Version 1

    RIP version 1 route advertisements do not include a field for the netmask. This means receiving routers have to gess the netmask based on whatever information they have available. That includes the "natural" netmask of that classful network. That also includes the receiving routers own...

    Jun 19, 2006
36. 6

    RIP Version 1

    RIP version 1 is a classful routing protocol. We cover the RIP packet format and configuration. We see examples of split horizon and triggered updates using the RIP debug commands.

    Jun 17, 2006
37. 5

    Static routing and introduction to CEF

    Routing protocols (and static routing) update the route table. The route table is used to forward packets. Cisco Express Forwarding (CEF) is a special route table optimized to forward packets more efficiently.

    Jun 13, 2006
38. 4

    Serial and ethernet point-to-point links

    We cable and configure ethernet and synchronous serial point-to-point links. In the next session these will be the "legs" of our triangle.

    Jun 11, 2006
39. 3

    Classful IP addressing

    Routers route packets based on the destination IP address: a 32-bit number included in the header of every IP packet. Historically, "large" sites were allocated IP address blocks starting with 0 (binary). Medium sites were allocated address blocks starting with the bits 10. "Small" sites were...

    Jun 8, 2006
40. 2

    Cisco 2500 password recovery

    Every network engineer needs to be able to deal with a router with an unknown password. Whether you are taking over a site where the previous engineer was "hit by a bus", or scrounging routers from the storage closet, good network engineers can deal with routers with unknown passwords.

    Jun 3, 2006
41. 1

    Scrounging Cisco Gear and Using the Console

    You can best take advantage of the Cisco training podcast series by getting routers and following along. First you need to scrounge or buy routers and cables. This episode helps you decide what to get. This episode also explains how to access the console.

    Jun 2, 2006