Learn Juniper and Cisco networking – with jokes!
BGP study guides tell you that loopback-to-loopback EBGP session require a TTL of 2 or more. The trouble is, they rarely say why. This leads new students to come to some very incorrect assumptions about how the TTL field works in IP. In fact though, you can absolutely have a TTL of 1! In this post we clear up all the confusion – and we even look at how you can use a TTL of 255 to bring extra security to your network.
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There’s three types of route distinguisher – and one of them unlocks some seriously useful advantages. If you don’t know how to use route distinguishers for load balancing inside an MPLS VPN, then this post is for you. Junos config, but vendor-neutral theory. Give it a read!
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A lot of websites tell you that the private AS range is 64512 to 65535. However, this isn’t quite correct – and the reason is really interesting. Click here to go on a BGP journey with me!
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Pseudowires are easy on the surface – but dig a bit deeper, and there’s some interesting complexity. Click here to learn the details about BGP-signalled L2VPNs!
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The independent-domain command is a little-known but big-useful command. Let’s see how we can use it in Junos to tunnel localpref info from one VPN customer site to another!
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In this post we use both Cisco IOS and Juniper Junos config to see the difference between route-distinguishers and route-targets in MPLS VPNs. Why do we need both of them? Click here to find out!
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There’s a few different ways of configuring a hub-and-spoke MPLS VPN. In this blog post we learn all about the “one interface” approach. Whether you’re an architect or a student of the JNCIE, you’ll want to know this one inside out!
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Hub-and-Spoke VPNs work a little differently than your regular full-mesh MPLS VPN. Want to learn the extra config required for this unique topology? Then click this post for some good learning!
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Routing policy in Junos can be a little confusing for beginners – but when it clicks, you’ll see that you can do some truly powerful stuff! Give this post a read to learn all about it!
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In Part 2 of this series we take a look at the label stack in Interprovider Option C. Plus, we look at the use case, and compare it to Option B. Plus: win a trillion pounds! (Not true)
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