4 ms·

How the U.S. National Science Foundation enabled Software-Defined Networking

121 points by zdw 1y ago

Animats 1y ago
> a network should have logically centralized control, where the control software has network-wide visibility and direct control across the distributed collection of network devices. Including a backdoor for wiretapping in SDN-enabled routers.
- blackmanta 1y ago
  Unless the goal of the backdoor is to redirect traffic flows through packet inspection devices that the attacker also controls, the decoupling of the control and data plane in SDN deployments requires a more creative, intricate solution to allow for wiretapping compared to traditional routers.
- acdha 1y ago
  Is it really a “back door” when it’s controlled by the network owner? It feels like we need a different term for that since it’s increasingly common on large networks.
  - Animats 1y ago
    The question is who can send commands as network owner. The basic idea of SDR is that when A wants to talk to B, a message is sent to some control point to determine the path. The path is then sent down to the routers along the path. Packets which ordinarily would go nowhere near eavesdropping point C can be redirected to go through C, on a per A/B pair basis.
heathermiller 1y ago
what a wonderful chronicle of how esoteric research became not-esoteric, and truly world-changing, and how the NSF enabled it pour one out for the NSF folks. RIP </3
zdw 1y ago
I worked with a quite few of the folks mentioned in this article when I was at the Open Networking Foundation, if anyone has questions.
- matt_daemon 1y ago
  What's your view on how these people actually impacted the adoption of SDN in general? > The investments NSF made in SDN over the past two decades have paid huge dividends. In my view this seems a little overblown. The general idea of separation of control and data plane is just that - an idea. In practice, none of the early firms (like Nicira) have had any significant impact on what's happening in industry. Happy to be corrected if that's not accurate!
  - zdw 1y ago
    Depends where you are in the industry - the hyperscalers specifically have budget to afford a team to write P4 or other SDN code to manage their networks in production, so they're probably the biggest beneficiaries. Lower end, it did make programmability more accessible to more folks and enabled whitebox switches to compete against entrenched players to a far greater extent than previously possible. Again, hyperscalers are going to be the main folks who buy this kind of gear and run SONiC or similar on it, so they can own the full switch software stack. Many of the startup companies in the SDN space did have successful exits into larger players - for example Nicira into VMWare, Barefoot (Tofino switch chip) and Ananki (the ONF 4G/5G spinoff) into Intel. Also, much of the software was developed as open source, and is still out there to be used and built on.
    - Maven911 1y ago
      What are some of the SDN open source software that is still useful today ? e.g. ODL, ONOS, Ryu, Floodlight
      - zdw 1y ago
        ONOS is being used with VOLTHA to enable PON networking in various locations (For example DT in Germany: https://convergedigest.com/deutsche-telekom-taps-open-source-voltha-for-fixed-access-infrastructure/ https://convergedigest.com/deutsche-telekom-taps-open-source... , and IIRC it's also in production in Turkey). There was a Comcast deployment to trial ONOS + whitebox switches a while ago. The specific interplay of commercial deployment to open source vs commercial closed source in the networking space was better described in this post from Larry Peterson: https://systemsapproach.org/2022/02/28/venn-diagram-engineering/ https://systemsapproach.org/2022/02/28/venn-diagram-engineer...
SurceBeats 1y ago
The 10-year research-to-production timeline is the key lesson. Today's funding (VC or government grants) demands results in 2-3 years. We've systematically eliminated the "patient capital" that creates foundational infrastructure imho...
- chuckadams 1y ago
  To say nothing of systematically eliminating the foundational infrastructure for nationally funded science in general.
- rjzzleep 1y ago
  In other words China's success is in part similar what used to make the US successful. Any lessons to be taken from that? No.
  - throwup238 1y ago
    The Chinese follow a five year cycle: https://en.wikipedia.org/wiki/Five-year_plans_of_China https://en.wikipedia.org/wiki/Five-year_plans_of_China The pattern is adopted from the Soviet Union. Take whatever lessons from that you will.
    - zorked 1y ago
      Oh, so onimous. Your claim is that the number 5 is cursed because it is a communist number? There is no lesson to take from the number 5. There are lessons to take from longer term planning.
      - throwup238 1y ago
        > Your claim is that the number 5 is cursed because it is a communist number? That’s your own nonsensical strawman, not mine. Who in their sane mind would stoop to such silly numerology? That sounds positively medieval. What were you even thinking when you wrote your reply? You’re going to really have to unpack your thought process for me to understand what you said.
themafia 1y ago
> 2003: The goal of the 100×100 project was to create communication architectures that could provide 100Mb/s networking for all 100 million American homes. Well you failed horribly. > The project brought together researchers from Carnegie Mellon, Stanford, Berkeley, and AT&T. I think I see why. > This research led to the 4D architecture for logically centralized network control of a distributed data plane What? How was this meant to benefit citizens? > Datacenter owners grew frustrated with the cost and complexity of the commercially available networking equipment; a typical datacenter switch cost more than $20,000 and a hyperscaler needed about 10,000 switches per site. They decided they could build their own switch box for about $2,000 using off-the-shelf switching chips from companies such as Broadcom and Marvell What role did the NSF play here? It sounds like basic economics did most of the actual work. > The start-up company Nicira, which emerged from the NSF-funded Ethane project, developed the Network Virtualization Platform (NVP)26 to meet this need Which seems to have _zero_ mentions outside of academic papers.
- xxpor 1y ago
  >Which seems to have _zero_ mentions outside of academic papers. Nicira or NVP?
- wmf 1y ago
  Nicira NVP is now VMware NSX which is pretty successful. AWS/GCP/Azure VPC are also probably inspired by Nicira.
coreyzzp 1y ago
What’s the current state of SDN development these days? I remember working on related projects about ten years ago in grad school, and even back then it felt like a somewhat naive and overhyped form of “engineering innovation.” Take OpenFlow, for example — every TCP connection had to go through the controller to set up a per-connection flow match entry for the path. It always struck me as a bit absurd. At the time, the main push came from Stanford’s “clean slate” networking project led by Prof. Nick McKeown. They spun off things like Open vSwitch, Big Switch Networks, and even open-source router efforts like NetFPGA. Later, the professor went back into industry. Looking back, the whole movement feels like a startup-driven experiment that got heavily “packaged” but never really solved any fundamental problem. I mean, traditional distributed-routing-based network gear was already working fine — didn’t they already have admin interfaces for configuration anyway (or call that admin interface SDN )? lol ~
- xxpor 1y ago
  It's all at the big cloud service providers. Not as much focused on the physical network (as originally imagined), but in the overlay networks. Seethe various DPUs like Intel IPU, Nvidia/Mellanox Bluefield, etc. Nvidia DOCA even uses OvS as the sort of example out of the box software to implement networking on Bluefield. When your controller is Arm cores 5 cm away on the same PCB doing per connection setup is no longer as absurd ;)
  - xxpor 1y ago
    s/Seeth/See/, wow.
- justahuman74 1y ago
  SDN is great if you're trying to build something like a multi-tenant cloud on top of another network of machines. Your DPUs can handle all the overlay logic as if there was a top of rack switch in each chassis
- wmf 1y ago
  A lot of mistakes were made. Almost all the code has been thrown away and all the details are different but maybe some of the ideas influenced things that exist today.
deleted 1y ago
[deleted]

121 points by zdw 1y ago

> a network should have logically centralized control, where the control software has network-wide visibility and direct control across the distributed collection of network devices. Including a backdoor for wiretapping in SDN-enabled routers.

blackmanta 1y ago
Unless the goal of the backdoor is to redirect traffic flows through packet inspection devices that the attacker also controls, the decoupling of the control and data plane in SDN deployments requires a more creative, intricate solution to allow for wiretapping compared to traditional routers.
acdha 1y ago
Is it really a “back door” when it’s controlled by the network owner? It feels like we need a different term for that since it’s increasingly common on large networks.
- Animats 1y ago
  The question is who can send commands as network owner. The basic idea of SDR is that when A wants to talk to B, a message is sent to some control point to determine the path. The path is then sent down to the routers along the path. Packets which ordinarily would go nowhere near eavesdropping point C can be redirected to go through C, on a per A/B pair basis.

heathermiller 1y ago

what a wonderful chronicle of how esoteric research became not-esoteric, and truly world-changing, and how the NSF enabled it pour one out for the NSF folks. RIP </3

zdw 1y ago

I worked with a quite few of the folks mentioned in this article when I was at the Open Networking Foundation, if anyone has questions.

matt_daemon 1y ago
What's your view on how these people actually impacted the adoption of SDN in general? > The investments NSF made in SDN over the past two decades have paid huge dividends. In my view this seems a little overblown. The general idea of separation of control and data plane is just that - an idea. In practice, none of the early firms (like Nicira) have had any significant impact on what's happening in industry. Happy to be corrected if that's not accurate!
- zdw 1y ago
  Depends where you are in the industry - the hyperscalers specifically have budget to afford a team to write P4 or other SDN code to manage their networks in production, so they're probably the biggest beneficiaries. Lower end, it did make programmability more accessible to more folks and enabled whitebox switches to compete against entrenched players to a far greater extent than previously possible. Again, hyperscalers are going to be the main folks who buy this kind of gear and run SONiC or similar on it, so they can own the full switch software stack. Many of the startup companies in the SDN space did have successful exits into larger players - for example Nicira into VMWare, Barefoot (Tofino switch chip) and Ananki (the ONF 4G/5G spinoff) into Intel. Also, much of the software was developed as open source, and is still out there to be used and built on.
  - Maven911 1y ago
    What are some of the SDN open source software that is still useful today ? e.g. ODL, ONOS, Ryu, Floodlight
    - zdw 1y ago
      ONOS is being used with VOLTHA to enable PON networking in various locations (For example DT in Germany: https://convergedigest.com/deutsche-telekom-taps-open-source-voltha-for-fixed-access-infrastructure/ https://convergedigest.com/deutsche-telekom-taps-open-source... , and IIRC it's also in production in Turkey). There was a Comcast deployment to trial ONOS + whitebox switches a while ago. The specific interplay of commercial deployment to open source vs commercial closed source in the networking space was better described in this post from Larry Peterson: https://systemsapproach.org/2022/02/28/venn-diagram-engineering/ https://systemsapproach.org/2022/02/28/venn-diagram-engineer...

SurceBeats 1y ago

The 10-year research-to-production timeline is the key lesson. Today's funding (VC or government grants) demands results in 2-3 years. We've systematically eliminated the "patient capital" that creates foundational infrastructure imho...

chuckadams 1y ago
To say nothing of systematically eliminating the foundational infrastructure for nationally funded science in general.
rjzzleep 1y ago
In other words China's success is in part similar what used to make the US successful. Any lessons to be taken from that? No.
- throwup238 1y ago
  The Chinese follow a five year cycle: https://en.wikipedia.org/wiki/Five-year_plans_of_China https://en.wikipedia.org/wiki/Five-year_plans_of_China The pattern is adopted from the Soviet Union. Take whatever lessons from that you will.
  - zorked 1y ago
    Oh, so onimous. Your claim is that the number 5 is cursed because it is a communist number? There is no lesson to take from the number 5. There are lessons to take from longer term planning.
    - throwup238 1y ago
      > Your claim is that the number 5 is cursed because it is a communist number? That’s your own nonsensical strawman, not mine. Who in their sane mind would stoop to such silly numerology? That sounds positively medieval. What were you even thinking when you wrote your reply? You’re going to really have to unpack your thought process for me to understand what you said.

themafia 1y ago

> 2003: The goal of the 100×100 project was to create communication architectures that could provide 100Mb/s networking for all 100 million American homes. Well you failed horribly. > The project brought together researchers from Carnegie Mellon, Stanford, Berkeley, and AT&T. I think I see why. > This research led to the 4D architecture for logically centralized network control of a distributed data plane What? How was this meant to benefit citizens? > Datacenter owners grew frustrated with the cost and complexity of the commercially available networking equipment; a typical datacenter switch cost more than $20,000 and a hyperscaler needed about 10,000 switches per site. They decided they could build their own switch box for about $2,000 using off-the-shelf switching chips from companies such as Broadcom and Marvell What role did the NSF play here? It sounds like basic economics did most of the actual work. > The start-up company Nicira, which emerged from the NSF-funded Ethane project, developed the Network Virtualization Platform (NVP)26 to meet this need Which seems to have _zero_ mentions outside of academic papers.

xxpor 1y ago
>Which seems to have _zero_ mentions outside of academic papers. Nicira or NVP?
wmf 1y ago
Nicira NVP is now VMware NSX which is pretty successful. AWS/GCP/Azure VPC are also probably inspired by Nicira.

coreyzzp 1y ago

What’s the current state of SDN development these days? I remember working on related projects about ten years ago in grad school, and even back then it felt like a somewhat naive and overhyped form of “engineering innovation.” Take OpenFlow, for example — every TCP connection had to go through the controller to set up a per-connection flow match entry for the path. It always struck me as a bit absurd. At the time, the main push came from Stanford’s “clean slate” networking project led by Prof. Nick McKeown. They spun off things like Open vSwitch, Big Switch Networks, and even open-source router efforts like NetFPGA. Later, the professor went back into industry. Looking back, the whole movement feels like a startup-driven experiment that got heavily “packaged” but never really solved any fundamental problem. I mean, traditional distributed-routing-based network gear was already working fine — didn’t they already have admin interfaces for configuration anyway (or call that admin interface SDN )? lol ~

xxpor 1y ago
It's all at the big cloud service providers. Not as much focused on the physical network (as originally imagined), but in the overlay networks. Seethe various DPUs like Intel IPU, Nvidia/Mellanox Bluefield, etc. Nvidia DOCA even uses OvS as the sort of example out of the box software to implement networking on Bluefield. When your controller is Arm cores 5 cm away on the same PCB doing per connection setup is no longer as absurd ;)
- xxpor 1y ago
  s/Seeth/See/, wow.
justahuman74 1y ago
SDN is great if you're trying to build something like a multi-tenant cloud on top of another network of machines. Your DPUs can handle all the overlay logic as if there was a top of rack switch in each chassis
wmf 1y ago
A lot of mistakes were made. Almost all the code has been thrown away and all the details are different but maybe some of the ideas influenced things that exist today.

deleted 1y ago

[deleted]