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Modulate Demodulate - The ModemCast

Modulate Demodulate - The ModemCast

By Modem Podcast
Hello, world. What is this MODEM podcast all about? Well, we saw a gap emerging in the technical podcast space. That gap was a deeply technical podcast, focused on the protocols, the details, the how-to-demistify-complex things, the unbiased, un-cola of networking that needed to be filled. We’re not interested in the marketing, or the fluff - we want to deconstruct the new shiny things and break them down into comsumable parts. Maybe also some witty banter.
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Unicast Use of the Formerly Reserved address blocks with Dave Taht and Seth Schoen

Modulate Demodulate - The ModemCast

So, you say you need 100G ethernet? A conversation about Mikrotik with Kevin Myers
So, you need a 100G router or switch, but are deeply concerned about:  Cost Power draw Cooling issues Price Capabilities Money Availability CapEX Never fear, for we have news of the front, and that news is encouraging. Once again we have Kevin Myers from IPArchitechs (not anointed an official co-host, for whatever that means), who - even according to Mikrotik is "part of the family - to tell us all the pieces, parts, details, and hidden gems about their new 100G platform, and we can confidently say, it's a doozey. So much greatness in here. We talk Mikrotik ROS7, 100G performance, unboxing (kevin had the first ones live in the US), future features, chipset capabilities, and as always, charming banter. Tune in and join Chris Cummings and Nick Buraglio along with Kevin, you won't be disappointed.  Marvell Prestera Switching Ship Family IPArchitechs CCR2216 CRS504
May 29, 2022
The Foibles and Frailties of IPv6 ULA
Yes, it’s ULA! The IPv6 addressing sensation that’s sweeping the nation! Free at participating Internet standards bodies and ULA generating websites... Get yours today! Warning: Pregnant women, the elderly, and children under 10 should avoidprolonged exposure to ULA. Caution: ULA may suddenly accelerate to dangerous speeds. ULA contains a liquid core, which, if exposed due to rupture,should not be touched, inhaled, or looked at. Do not use ULA on dual-stacked networks. Discontinue use of ULA if any of the following occurs: Weird behaviours on different versions of an operating systm Itching Vertigo Dizziness Tingling in extremities Inconsistent reachability to dual-stacked destinations Loss of balance or coordination Slurred speech Temporary blindness Profuse sweating or heart palpitations. If ULA begins to smoke, get away immediately. ULA also may stick to certain types of skin. When not in use, ULA should be returned to its special container and kept under refrigeration. The Ingredients of ULA include an unknown glowing green substance, which fell to Earth, presumably from outer space. Do not taunt ULA. ULA! Accept no substitutes! Links Mentioned RFC 4193  RFC 6724  RFC 3484  IPv6 Buzz  ULA is broken in dual-stacked networks
April 09, 2022
Unicast Use of the Formerly Reserved address blocks with Dave Taht and Seth Schoen
We’ve been busy! At least that’s our excuse. We recorded this episode with Dave Taht and Seth David Schoen about some new drafts they wrote for the Unicast Use of the Formerly Reserved address blocks such as, and a few others, back in February. Needless to say, it was pretty interesting. Full of very polarizing topics (for oh-so-many reasons) this winding and wandering podcast lays out the history as well as the justifications for taking such address blocks - historically held as “untouchable” - and advocates for moving them into general use. Take a listen and decide for yourself! Links Mentioned Unicast Use of the Formerly Reserved 240/4 The IPv4 Cleanup Project GitHub Repo Original Bufferbloat MODEM episode with Dave MODEM DoD Space Episode ISI mailing list AWS Reachability Page
April 09, 2022
Make Labbing Less Miserable With netsim-tools
Is this a crossover episode? Ivan Pepelnjak of and the SGW Podcast joins Chris Cummings and Nick Buraglio to discuss his latest project, netsim-tools! Tune in to learn about how Ivan has gone all-in on using Infrastructure as Code (IaC) prinicipals for building network labs with his latest project netsim-tools. This project lets you not only define your lab topology using a declarative syntax, but also removes the minutia of building a lab by pre-configuring all of the basics for you. Listen to learn more about all the juicy details! Links Mentioned netsim-tools Docs netsim-tools GitHub Repo MODEM Containerlab Episode e markdown.
February 12, 2022
Underlays and Overlays - A Networking Field Day Service Provider Retrospective
Tune in to MODEM as Kevin Myers and Vince Schuele join Nick Buraglio and Chris Cummings to discuss their thoughts around the inaugural Networking Field Day Service Provider! Links Mentioned Networking Field Day Service Provider IP ArchiTechs Stub Area 51 The Ramp Room blog by John Osmon CORD
December 21, 2021
More on RouterOS v7.1 with Kevin Myers
Once again we're behind on publishing! Recorded this episode with Kevin Myers right after the ZeroTier on RouterOS was released into the wild. We've had some drive time with it now, and we all believe one thing: it's worth your time. A lot of other greatness in here, LDPv6, IPv6 chatter, and delightful banter. Enjoy! Links Mentioned IP ArchiTechs Kevin's Blog RouterOS v7 First Look RouterOS v7 Performance Testing PQ 134: Meet ZeroTier – Open Source Networking  
November 01, 2021
Learn from our experience; or hey, get off my lawn.
Off for the summer - after a short hiatus we're back! Actually, we recorded this in July (of 2021) but then summer ramped into full swing and editing took a back burner.  With this episode we shift gears, change direction, flip-flop, do a roundabout and talk about less technical topics. We all have ways that we learn, and hindsight is 20/20. In this from-the-heart and retrospective episode, Chris Young, Nick Buraglio, and John Osmon wax poetic about the the things we wish we knew and dole out our deepest, most sincere learn-from-our-experience advice. We get deep, but we go old school and make it personal.  Welcome to fall, everyone. Terry Slattery talks about packet loss and the Mathis equation Interop
September 27, 2021
Containerlab: Declarative Network Labbing with Roman Dodin
Building large-scale network labs can be tedious and error prone—More importantly, they can be notoriously hard to spin up automatically. Containerlab is a new tool that promises to "redefine the way you run networking labs" and I really think it hits that target. On this episode of the Modulate Demodulate podcast, Nick and Chris C. are joined by Roman Dodin, one of the brains behind Containerlab. Find Containerlab Online Containerlab Website Containerlab Twitter Containerlab Github Links Mentioned Networking Field Day 25 Nick's "Github 'O Configs" VRNetlab iPerf3
June 06, 2021
Deep Dive into Thread with Jonathan Hui
Deep Dive into Thread with Jonathan Hui Welcome back to the Modem podcast where we visit some of the dark and musty corners of the network and shine lights in pars of the network that many people haven’t touched before. For many of us in main stream networking, we’re all about more. More bandwidth, more control. Bigger pipes. Faster switches etc… but there’s whole other spectrum that I’ve started to dive into over the last year that I wanted to bring to the table to discuss to prove that sometimes, more bandwidth isn’t the answer to everything, and that indeed, size matters, and sometimes, just sometimes, smaller is better. Recently the smart home space has been abuzz when there suddenly appeared a new protocol on the scene that was all the new hotness called “Thread”. Now like many protocols, it wasn’t really new at all, but was really just new to many of us who have never taken the time to dig into the interesting world of low-power low-data networking. Luckily we have a special guest with us today to take by the hand and help us remember that everything in networking has it’s place. Even RIP. In this episode, we welcome Jonathan Hui, CTO of the Thread Group to the show to take us down the rabbit whole into the history of this protocol, enlighten us to microverse of low-power/low-bandwidth networking, and help us remember that BGP isn’t the answer for everything. Learn More about Thread Thread Group Website Thread Group Resources Thread Networking Fundamentals Connect on Social Media Jonathan on Twitter The Thread Group on Twitter The Thread Group on LinkedIn
May 19, 2021
ARTEMIS: Making BGP Operations Suck Less
BGP is one of the most versatile routing protocols out there, but let's be honest—It kinda sucks when it comes to... Well, a lot of things. Specifically, there are a lot of issues with BGP's security (or lack thereof). BGP comes from a time when The Internet was much smaller and everyone knew everyone. Now that The Internet has exploded in growth, hijacks, both malicious and inadvertent, have required countless hours of pain-staking manual intervention and deep knowledge of BGP and the global routing table to diagnose—keeping your routes secure in this landscape almost seems like a sisyphean task. Cue ARTEMIS. ARTEMIS (Automatic and Real-Time dEtection and MItigation System) does the hard work of detecting hijacks for you and it can even step in and attempt to mitigate them on your behalf. Okay, that sounds great, but how much does it cost? Nothing! ARTEMIS is free, open source, and even simple to install and use. Check out this episode of the Modulate Demodulate podcast as the lead developer for ARTEMIS and Co-founder/CTO of Code BGP, Vasileios Kotronis joins Chris C. and Nick to talk about the inner-workings of ARTEMIS. Find ARTEMIS Online ARTEMIS Website ARTEMIS Twitter ARTEMIS Github ARTEMIS Documentation ARTEMIS Slack Community ARTEMIS Live Demo Links Mentioned Route Views Project RIPE RIS CAIDA BGPStream MANRS ExaBGP ARTEMIS IEEE Paper ARTEMIS BGP Hijacking Survey with Network Operators Paper
May 02, 2021
Packet loss is good. Wait, what? Let's talk about Buffer Bloat with Dave Täht.
Buffer Bloat. Most folks in the networking industry have at least heard this term, and may have a vague idea of what it means. It's certain that all of us have experienced it at one time or another - and likely thought it was a different problem. Over the last few years a couple of queuing disciplines have emerged that have allowed the users of the internet to experience fewer and fewer of those odd symptoms, and we wanted to know more about how those problems are getting solved. Fortunately, we managed to pin down Dave Täht and get him to talk to us about fq_codl and cake. Or so we thought. Turns out, that's a really, really big topic. Luckily, we had the expert to take time and really get down to the root of the problem, how it is solved, and give us a fantastic bit of history about how it came to be. This one has it all, folks. Boats, guitars, stickers, Dave even plays us a song at the end. It's a fun one, and the deep knowledge does not disappoint. Join me, Chris Cummings, Dan Siemon, and Dave Täht as we wander through the complex forest of buffer bloat, queuing codecs, and queue theory. Bufferbloat and Beyond Book Netstat command for looking at fq_codl: Linux tc -s qdisc show dev eth0 netstat -c fq_codel -vvv OSX  netstat -c fq_codel -vvv Benchmarking fq_codel SFQ, DRR, SQM, other queuing disciplines The Flow Queue CoDel Packet Scheduler and Active Queue Management Algorithm Photo: 
April 12, 2021
Through the Looking Glass with Darren O'Connor
Tune in to this installment of Modulate Demodulate as Darren O'Connor joins Chris C., Nick, and Dave to discuss his side project— This tool is a modern BGP looking glass built in Golang that anyone can use to gather a wealth of information on the BGP Routing table. Some of the things you can see are AS_Path, Origin AS, ROA, ASName, RPKI Invalids, DFZ RIB size, and more. In addition to a nice web interface, the latest version of BGPStuff introduces an updated RESTful API. Come check out our discussion of the architecture and technology behind! Links Mentioned BGPStuff Presentation Darren's VirtualNOG Project BGPStuff Python Client ASN Bogon Validation Python Library BGP6-Table TwitterBot BGP4-Table TwitterBot
March 21, 2021
[Non-Blocking] The DoD Brinks Truck of IPv4 Space
On this first episode of the MODEM Non-Blocking series, Nick and Chris C. wax ineloquent about the latest networking gossip straight from the DFZ. Recently, the DoD started announcing a lot of IPv4 address space that had been previously unannounced. How much is a lot? We're talking 13 /8s of IPv4. Tune in to hear our un-scripted thoughts on what this might mean for your network, The Internet as a whole, and the deployment of IPv6. Links Mentioned Hilco Blog Post AS8003 Team Cymru Bogons NANOG Thread on DoD v4 Space Being Treated as Bogons NANOG Thread on DoD v4 Space Being Announced Cloudflare Research AMPRnet 44/8 Official Statement
March 17, 2021
The Latest in RouterOS v7 with Kevin Myers
On this episode of the MODEM Podcast, Nick and Chris C. bring on a special guest, Kevin Myers, to talk about the latest software updates from one of the underdogs of networking—MikroTik. MikroTik RouterOS v7 is the next version of MikroTik's routing software that promises to solve a lot of the longest-standing requests from users. Kevin and his consulting firm IP ArchiTechs have been hands-on users of MikroTik since the early days, so come and listen to us discuss multi-threaded BGP, IS-IS, RPKI, and maybe even a few war stories! Links Mentioned IP ArchiTechs Kevin's Blog RouterOS v7 First Look RouterOS v7 Performance Testing MikroTik IS-IS Forum Thread MANRS
March 07, 2021
What the heck is a tunnel? OK, then, what is a VPN?
How hard is it to describe the difference between a tunnel and a VPN to a completely non-technical person? Come to find out, it is fairly difficult! Chris Young - one of our esteemed co-hosts - tweeted out a seemingly simple question: “Explain the difference between a tunnel and a VPN to a non/technical audience.”. Proposed answers were given, a variety of interpretations of "non-technical audience" were made. Hilarity ensued. which really begs the questions: what the heck ARE tunnels? What are VPNs? Think you know? So did we. Take a trip with us through our winding exploration as we dive into the abyss of the ocean of possibilities - all aboard the RV Calypso of encapsulation. List of Tunneling mechanisms: Encapsulation VXLAN GENEVE GRE mGRE NVGRE OTV IP in IP 6 in 4 4 in 6 EoIP PPTP CAPWAP DTLS GTP (GPRS Tunnelling Protocol) Q-in-Q IPSec L2TP HTTPS Tunnelling DNS Tunnelling SSH Tunnelling TOR L2F ISATAP Teredo Wireguard MACSEC Control Plane EVPN L2VPNs L3VPNs MVPN Label Stacks LDP VPLS RSVP-TE SR (V6/MPLS) 128T (NDN-esque) DOVE All in One ZeroTier Wireguard
February 22, 2021
Understanding the Internet Exchange with Mike Hammett
As the internet grows and changes, it has become increasingly important for organizations of a certain size to dive into external routing. As many that start this path soon find, there is a wealth of information about setting up peering, configuring BGP and the associated policy, and how to connect to an "Internet Provider". But what if your internet provider is not quite enough anymore? What happens if you need lower latency to a cloud provider? Or, to take it one step further, what can you do to further settlement free peering in your geographical area?  That is there the Internet Exchange Point (IX) come in to fill the gap. On this episode of the MODEM Podcast, Chris C., Nick, and John talk to Mike Hammett of the Midwest IX about what an IX is, what it does, and how to build your own.   IPSpace: Surviving in the default free zone webinar The Brothers WISP Podcast
January 17, 2021
FRR protocol updates with Donald Sharp
FRR is a well traveled and well established routing suite. It has a comprehensive and very complete stable of protocol support, which is ever expanding. In this episode, Chris Y., David, and Nick chat with Donald Sharp about some of the finer details of the newer protocol support including IPv6 FlowSpec, BGP BMP, and IS-IS-SR. We delve into the finer points of component integration, discuss the nuance of how tunneling interfaces work, take a walk down the edge of why IS-IS is less traveled (including some of the fun protocol details therein). We even give a pretty fun little jaunt into the origin story of FRR. 
January 08, 2021
Behavior Tree Concepts in Network Management with Tomas Kirnak
Behavior Tree concepts are something that most network engineers probably do not spend a lot of thinking about on a day-to-day basis, but their usefulness and relative ease of understanding will be made clear by the guest of our inaugural podcast, Tomas Kirnak. Tomas is the CEO of a company called Unimus that leverages behavior tree concepts to make configuration backup and automation of network hardware very straightforward. In this episode, John, Chris C. and Nick tease apart the details of what it takes to make that process as pain free as possible - and oh, boy, it is some cool stuff.
January 08, 2021