Largest netsim-tools Topology I’ve Seen So Far

I stumbled upon a blog post by Diptanshu Singh discussing whether IS-IS flooding in highly meshed fabric is as much of a problem as some people would like to make it. I won’t spoil the fun, read his blog post ;)

The really interesting part (for me) was the topology he built with netsim-tools and containerlab: seven leaf-and-spine fabrics connected with WAN links and superspines for a total of 68 instances of Arista cEOS. I hope he automated building the topology file (I’m a bit sorry we haven’t implemented composite topologies yet); after that all he had to do was to execute netlab up to get a fully-configured lab running IS-IS.

Largest netlab Topology I’ve Seen So Far

I stumbled upon a blog post by Diptanshu Singh discussing whether IS-IS flooding in highly meshed fabric is as much of a problem as some people would like to make it. I won’t spoil the fun, read his blog post ;)

The really interesting part (for me) was the topology he built with netlab and containerlab: seven leaf-and-spine fabrics connected with WAN links and superspines for a total of 68 instances of Arista cEOS. I hope he automated building the topology file (I’m a bit sorry we haven’t implemented composite topologies yet); after that all he had to do was to execute netlab up to get a fully-configured lab running IS-IS.

Video: Typical Kubernetes Inter-Pod Traffic Walk

Stuart Charlton did his best to explain the concept of pods in the Kubernetes Networking Deep Dive webinar, but we were still a bit confused. Next step: let’s talk about typical inter-pod traffic scenario.

Video: Typical Kubernetes Inter-Pod Traffic Walk

Stuart Charlton did his best to explain the concept of pods in the Kubernetes Networking Deep Dive webinar, but we were still a bit confused. Next step: let’s talk about typical inter-pod traffic scenario.

Is OpenFlow Still Kicking?

Continuing the how real is the decade-old SDN hype thread, let’s try to figure out if anyone still uses OpenFlow. OpenFlow was declared dead by the troubadour of the SDN movement in 2016, so it looks like the question is moot. However, nothing ever dies in networking (including hop-by-hop IPv6 extension headers), so here we go.

Why Would One Use OpenFlow?

Ignoring for the moment the embarrassing we solved the global load balancing with per-flow forwarding academic blunders¹, OpenFlow wasn’t the worst tool for programming forwarding exceptions (ACL/PBR) into TCAM.

Is OpenFlow Still Kicking?

Continuing the how real is the decade-old SDN hype thread, let’s try to figure out if anyone still uses OpenFlow. OpenFlow was declared dead by the troubadour of the SDN movement in 2016, so it looks like the question is moot. However, nothing ever dies in networking (including hop-by-hop IPv6 extension headers), so here we go.

Why Would One Use OpenFlow?

Ignoring for the moment the embarrassing we solved the global load balancing with per-flow forwarding academic blunders¹, OpenFlow wasn’t the worst tool for programming forwarding exceptions (ACL/PBR) into TCAM.

SDN Controller Taxonomy

Even though Gartner declared SDN obsolete before plateau in their 2021 Networking Hype Cycle, most vendor marketers never got the memo. Anything that interacts with network devices in any way¹ is called an SDN controller. Let’s try to throw some minimal amount of taxonomy into that mess based on how these controllers interact with network elements (physical or virtual).

SDN Controller Taxonomy

Even though Gartner declared SDN obsolete before plateau in their 2021 Networking Hype Cycle, most vendor marketers never got the memo. Anything that interacts with network devices in any way¹ is called an SDN controller. Let’s try to throw some minimal amount of taxonomy into that mess based on how these controllers interact with network elements (physical or virtual).

Ethernet Encryptor Market Overview (2022 Edition)

Christoph Jaggi, the author of Ethernet Encryption webinar, published a new version of Ethernet Encryptor Market Overview including:

• Network standards and platforms
• Data plane encryption
• Control plane security
• Key- and system management
• Relevant approvals
• Vendors and products, including detailed feature support matrices.

Ethernet Encryptor Market Overview (2022 Edition)

Christoph Jaggi, the author of Ethernet Encryption webinar, published a new version of Ethernet Encryptor Market Overview including:

• Network standards and platforms
• Data plane encryption
• Control plane security
• Key- and system management
• Relevant approvals
• Vendors and products, including detailed feature support matrices.

Networking Hardware/Software Disaggregation in 2022

I started preparing the materials for the SDN – 10 years later webinar, and plan to publish a series of blog posts documenting what I found on various aspects of what could be considered SDN¹. I’m pretty sure I missed quite a few things; your comments are most welcome.

Let’s start with an easy one: software/hardware disaggregation in network devices.

Open-Source Network Operating Systems

I found several widely-used open-source² network operating systems:

Networking Hardware/Software Disaggregation in 2022

I started preparing the materials for the SDN – 10 years later webinar, and plan to publish a series of blog posts documenting what I found on various aspects of what could be considered SDN¹. I’m pretty sure I missed quite a few things; your comments are most welcome.

Let’s start with an easy one: software/hardware disaggregation in network devices.

Open-Source Network Operating Systems

I found several widely-used open-source² network operating systems:

Worth Reading: Using LEO and GEO Satellite Internet

Another interesting column by Geoff Huston: performance of TCP congestion control protocols when using Low-Earth Orbit or Geosynchronous Orbit satellites for Internet access.

Worth Reading: Using LEO and GEO Satellite Internet

Another interesting column by Geoff Huston: performance of TCP congestion control protocols when using Low-Earth Orbit or Geosynchronous Orbit satellites for Internet access.

Video: Network Address Assignments

The last part of Network Addressing section of How Networks Really Work webinar covered other addressing-related topics starting with address assignment mechanisms.

Video: Network Address Assignments

The last part of the Network Addressing section of How Networks Really Work webinar covered other addressing-related topics starting with address assignment mechanisms.

Is Fibre Channel Still a Thing?

Here’s another “do these things ever disappear?” question from Enrique Vallejo:

Regarding storage, is Fibre Channel still a thing in 2022, or most people employ SATA over Ethernet and NVMe over fabrics?

TL&DR: Yes. So is COBOL.

To understand why some people still use Fibre Channel, we have to start with an observation made by Howard Marks: “Storage is different.” It’s OK to drop a packet in transit. It’s NOT OK to lose data at rest.

Is Fibre Channel Still a Thing?

Here’s another “do these things ever disappear?” question from Enrique Vallejo:

Regarding storage, is Fibre Channel still a thing in 2022, or most people employ SATA over Ethernet and NVMe over fabrics?

TL&DR: Yes. So is COBOL.

To understand why some people still use Fibre Channel, we have to start with an observation made by Howard Marks: “Storage is different.” It’s OK to drop a packet in transit. It’s NOT OK to lose data at rest.

netsim-tools: VLANs, Hardware Labs, VRF Loopbacks

Here’s a short list of major goodies included in netsim-tools release 1.2.2:

• Access VLANs, VLAN trunks and native VLANs implemented on Cisco IOS, Arista EOS, VyOS, and Dell OS10 (VyOS and OS10 support contributed by Stefano Sasso)
• Hardware labs implemented with external topology provider (contributed by Stefano Sasso)
• VRF loopback interfaces (contributed by Stefano Sasso)

More details in the release notes.

To upgrade netsim-tools, use pip3 install --upgrade netsim-tools; if you’re starting from scratch, read the installation instructions.

New in netlab: VLANs, Hardware Labs, VRF Loopbacks

Here’s a short list of major goodies included in netsim-tools release 1.2.2:

• Access VLANs, VLAN trunks and native VLANs implemented on Cisco IOS, Arista EOS, VyOS, and Dell OS10 (VyOS and OS10 support contributed by Stefano Sasso)
• Hardware labs implemented with external topology provider (contributed by Stefano Sasso)
• VRF loopback interfaces (contributed by Stefano Sasso)

More details in the release notes.