Home Lab – routingloop.net

TCP CUBIC vs BBR Pt. 1

TCP congestion control algorithms have a tough problem to solve. They need to estimate the available capacity of a network path without any knowledge of network. Remember that TCP runs in the end hosts. It’s important to estimate the network capacity to achieve the maximum throughput for a single flow while sharing network resources with

Don’t Have a Bad Day

31MarchStevenHome Lab, Routing

Anycast RP with Multicast Source Discovery Protocol (MSDP) is a great way to provide fault tolerance to your multicast network. Configure another router with the RP address, bang out a few msdp commands on the RP routers and you’re all set for a basic anycast RP design. It’s important to not get tunnel vision and

EIGRP Metric Calculation

27MarchStevenHome Lab, Routing

If you’ve worked with or studied EIGRP, you’ve probably seen that scary formula with the K values that EIGRP uses to calculate routing metrics. It turns out that if you’re using the default K values so that only bandwidth and delay are being considered, the math involved isn’t that bad. In this article we’ll explore

IPv6 Next Hop

16MarchStevenHome Lab, IPv6, Routing

Over the last two weeks I’ve been focusing on strengthening my knowledge of IPv6 and it got me thinking about usage of link local addresses as the next hop for routing. It became apparent that this difference from IPv4 makes it possible to have equal cost next hops via the same output interface and for

IPv4 Fragmentation

2MarchStevenHome Lab, Routing

One of the attributes that helped IPv4 stand the test of time is the ability to slice and dice big datagrams into multiple smaller ones on the fly. This provides tremendous flexibility for different data links and their maximum packet size, reduced MTUs inside of tunnels, and the like. The process of chopping up IP

Joining MST and PVST Domains

16FebruaryStevenHome Lab, Switching

Multiple Spanning Tree Protocol (MST) allows network operators to map one or more VLANs to a Spanning Tree Protocol instance. For example, VLANs 1,2,3,4, and 5 can be mapped to STP instance 1 while VLANs 6,7,8,9 and 10 are mapped to STP instance 2. Consolidating multiple VLANs into a single STP instance requires less overhead

Spanning Tree BackboneFast

8FebruaryStevenHome Lab, Switching

To close out this 3-part series on Spanning Tree convergence optimizations we’ll be diving into Spanning Tree BackboneFast. This feature allows “classic” STP 802.1D bridges to converge faster when a remote bridge loses connectivity to the root bridge, i.e. this allows faster convergence to indirect link failure. Demo Network To demonstrate convergence with and without

Spaghetti

8FebruaryStevenHome Lab

PIM RP Redundancy that (kinda) Works

10JanuarySteven1 CommentHome Lab, Routing

I spent a few minutes thinking about anycast RP for PIM sparse-mode deployment and thought of a way to provide RP redundancy without auto-RP or BSR to dynamically learn RPs, and without using MSDP to synchronize active source information between anycast RPs. There is a major pitfall to this approach but it can work. Demo

STP Priority

31DecemberStevenHome Lab, Switching

When learning protocols, I like to build out a lab, take packet captures, debugs, and show commands and try to understand and justify the output. My most recent exercise is with PVST+. I built out the 6-switch topology below in CML. One of the first things I experimented with is bridge priority configuration. VLAN 10

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Category Archives: Home Lab