Skip to main content

Route This Way: Introduction To Routing Protocols + RIP

Less 'introduction' and more "Well, I paid and studied to take the CCNA, so I'm going to put this information to use somehow."




Also, apparently network administrators feel very strongly about their routing protocol of choice, and will fight people over it.

To be clear, I'm 🤔 at the person who went through all that effort to make an account to do this. I have that kind of time as well, but I'm not doing that, I'm doing this.


So, what is a Routing Protocol?

Graphic Design in My Passion

Routing protocols do a lot of the configuring for you on a network. No need for incessantly typing in static routes, which don't scale easily across a large network and take up a lot of time.

Distance Vector -
  • How far away is the destination. This is usually counted via hops.
  • Slower convergence because it sends the entire routing table.
  • Prone to loops.

Link State -
  • The router knows about every other router and it's, well, link state. 
  • The only information that is sent or received is changes in links - are they up or down?
  • Converge much quicker, at the cost of using more CPU.
  • Has three tables:
    • Neighbor - "Who's running the same routing protocol?"
    • Topology - "Where is everybody?"
    • Routing  -"How can I get to this place quickest?"
Let's start with RIP, so this post isn't woefully short:


Here is the topology so far; The following configurations are focused on the highlighted bits.



Configuration is simple:

I don't recall version 1 being used...a ton - or at all in the learning present day - so we're going with version 2.


Everything in the 192.168 and 10 networks are being advertised to Router 2 (on the left).

 show ip route



The 10 and 192.168.1 networks are 'directly connected', as they're on the same router where I ran the command.

Let's set up Router 2 (on the left) and show ip route again on router 1.


The highlighted area says "Yes, we're connected with the RIP routing protocol.". We can also stop the PCs from receiving RIP updates with the passive-interface command within the routing protocol configuration:

passive-interface [int]

 This network is small, so the 15 hop count limit that plagues RIP will be no issue here. But what if the network was far bigger?

Keep reading.

Comments

Popular posts from this blog

Connecting IoT Devices to a Registration Server (Packet Tracer, Cisco)

 If you're seeing this post, I'm helping you, and you probably have LI presence: React and share this post to help me in return.   In Packet Tracer, a demo software made by Cisco Systems. It certainly has changed a lot since 2016. It's almost an Olympic feat to even get started with it now, but it does look snazzy. This is for the new CCNA, that integrates, among other things, IoT and Automation, which I've worked on here before. Instructions here . I don't know if this is an aspect of "Let's make sure people are paying attention and not simply following blindly", or an oversight - The instructions indicate a Meraki Server, when a regular one is the working option here. I have to enable the IoT service on this server. Also, we assign the server an IPv4 address from a DHCP pool instead of giving it a static one. For something that handles our IoT business, perhaps that's safer; Getting a new IPv4 address every week or so is a minimal step against an...

Create a Simple Network (Packet Tracer) + A Walkthrough

Again; I've done this, but now there's so many new things, I'm doing it again. The truly new portions were...everything on the right side of this diagram; The cloud needed a coax connector and a copper Ethernet connector. It's all easy to install, turn off the cloud (Weird), install the modules. Getting the Cable section of Connections was an unusual struggle - The other drop down menu had nothing within. It required going into the Ethernet options and setting the Provider Network to 'cable', which is the next step AFTER the drop-downs. The rest was typical DHCP and DNS setups, mainly on the Cisco server down there. The post is rather short - How about adding a video to it? Find out what A Record means - This site says 'Maps a name to an IP address', which is DNS. So it's another name for DNS? You can change them (presumably in a local context) to associate an IP address to another name.

Securing Terraform and You Part 1 -- rego, Tfsec, and Terrascan

9/20: The open source version of Terraform is now  OpenTofu     Sometimes, I write articles even when things don't work. It's about showing a learning process.  Using IaC means consistency, and one thing you don't want to do is have 5 open S3 buckets on AWS that anyone on the internet can reach.  That's where tools such as Terrascan and Tfsec come in, where we can make our own policies and rules to be checked against our code before we init.  As this was contract work, I can't show you the exact code used, but I can tell you that this blog post by Cesar Rodriguez of Cloud Security Musings was quite helpful, as well as this one by Chris Ayers . The issue is using Rego; I found a cool VS Code Extension; Terrascan Rego Editor , as well as several courses on Styra Academy; Policy Authoring and Policy Essentials . The big issue was figuring out how to tell Terrascan to follow a certain policy; I made it, put it in a directory, and ran the program while in that ...