Remembering Dave Taht

  

“Elon, let me inside this thing, and I can fix it for you” (Image from this podcast)

In my own mind, I like to think of him as the person who added the most effective capacity to the Internet, Karl Auerbach

Dave Taht died on April 1st. I met him only recently, and never in person, but his passing saddens me. His technical work and evangelism have improved the Internet, and I will give some examples of his contributions to the Internet community and users, but I am sad because he was a good person — idealistic, unselfish, open, and funny. I'll miss him. First, his contributions, then his values.

Contributions

Taht was best known for his work on buffer bloat and its impact on Internet performance. As packets hop across the Internet, they are queued in buffers while waiting to be forwarded.  Long queues, “buffer bloat,” means increased latency, transit time between a source and its destination, and jitter, transit time variance.

Internet service providers typically advertise and price based on service speed, but latency is critical to interactive applications like gaming, teleconferencing, and Web surfing. (For a deep dive on buffer bloat, see this post by Jim Gettys, who coined the term buffer bloat.)

With Jim Gettys, Taht co-founded the buffer bloat Project, where he implemented, tested, and integrated active queue management (AQM) algorithms CoDel, FQ-CoDel, and CAKE, and led the CeroWRT (Customer Edge Router Wireless Router) project that focused on home, office, and other edge networks.

Gettys shared Taht's focus on the edge, writing “Surprising to most, AQM is essential for broad band service, home routers, and even operating systems: it isn't just for big Internet routers” in 2011 and more recently he said “Buffer bloat can happen anywhere in a network, though by far the most common locations are before/after the WiFi hop in the router, and then the hop from the home router back to the ISP”

Given his interests in space and edge networks, Starlink was a natural focus for Taht, and he talked about Starlink in this 8-minute podcast excerpt. Taht had known Elon Musk since he had worked on an ill-fated satellite that was on a Falcon 1 rocket when it blew up, so he emailed Musk in 2013 and offered to help, but Musk was not interested. The plan for Starlink was announced in January 2015, and when it eventually entered beta in 2020, Taht learned of the latency problem and emailed Vint Cerf, who arranged a meeting with Starlink engineers on Taht’s boat, but he did no work for them.

In January 2024, Elon Musk announced that “the biggest single goal for Starlink from a technical standpoint is to get the mean latency below 20 ms." By March, they were delivering results and listing latency as well as upload and download speed on their availability map. Unfortunately, Musk and his engineers did not listen to Taht in 2013 and 2020.

 

Starlink latency improvement after January 2024 (Source)

Values

The National Science Foundation backbone network (NSFNET) was created in 1986 to serve research and education in the US. The network grew rapidly, and in 1988, access was expanded to include international research and education organizations. By 1996, 28 nations were connected. (Fun fact – Cuba’s first link was to NSFNET.)

Taht was 30 years old when NSFNET was decommissioned and the Internet transitioned to fully commercial operation, but his values were established by then. With his skill and experience, he could have found lucrative work or built a large company, but he was committed to open-source software and universal connectivity.

Everything he wrote was open-source, including his songs. He is surely the only composer/musician to write geeky songs about the Internet, for example, this little ditty about the GNU Public License, Richard Stallman, Linus Torvalds, and Eric Raymond. He also spent years in Nicaragua, trying to find ways to bring the Internet (and power, lighting, food, medicine, and books) there as an outgrowth of Nicholas Negroponte’s One Laptop Per Child project.

He understood J. C. R. Licklider’s conception of the Internet as a means of creating communities of common interest rather than common location. He created a Starlink list, which is where I met him. The caliber of conversation on the list is an implicit tribute to Taht.

The photo of Taht at the top of this post was taken from the podcast in which he offered to fix the Starlink router, which was in beta at the time, for free (though he wouldn’t mind a thank-you tweet, a new motor for his boat, or even a Christmas card). The photo illustrates his values. He could have lived in a mansion, but he chose to live on a boat with a guitar nearby. To know Dave Taht better, watch the entire video.

Appendix

I met Dave recently and only knew him online, so I asked Perpleity, Gemini, Grok, and ChatGPT to list memorials. They returned several broken links, and Claude and Deepspeak were not current. I found these:

Author: Doc Searls
Title: Remembering Dave Taht
Link

Author: Steven J. Vaughan-Nichols
Title: Dave Taht, Who Sped Up Networks More Than You’ll Ever Know, Has Died
link

Author: Tom Stricx
Title: Honoring Dave Täht and his contributions to a better Internet (video calls included)
Link
 
Authors: Robert, Herbert, and Frank LibreQoS
Title: In loving memory of Dave Taht
Link
 
Author: Hacker News Community
Title: Thread collecting memories, technical anecdotes, and condolences from the networking and open source community
Link
 
Author: Toke Høiland-Jørgensen
Title: Remembering Dave Taht, Link
Link

Starlink is critical in support of Ukraine, and it will continue

Ukrainian drone boat with two Starlink terminals (source Oleg Kutkov)

At 4:04 AM on February 26 Mykhailo Fedorov, Vice Prime Minister and Minister of Digital Transformation of Ukraine, requested Starlink service from Elon Musk, and at 2:45 PM on the 26th, Elon Musk tweeted "Starlink service is now active in Ukraine. More terminals en route." On February 28 at 12:29 PM Fedorov posted a photo of a truckload of terminals. (Kyiv is 10 hours ahead of California) and an engineer, Oleg Kutkov, posted the first tweet from Ukraine, showing a download speed of 136.76 Mb/s and an upload speed of 23.93 Mb/s.  (Kutkov was among the "people embodying the spirit of Ukraine," chosen by Time Magazine as Person of the Year for 2022).

On March 19^th there were 5,000 terminals in Ukraine and it was clear that Starlink would play an unprecedented, critical role in the war. President Zelenskyy was using social media and teleconferencing in his roles as Commander in Chief of the armed forces, a global diplomat, and a leader of the Ukrainian people. Starlink was being used to compensate for Russian destruction of Ukrainian infrastructure, by civilians and on the battlefield, often in conjunction with drones. Starlink has also enabled important civilian volunteer contributions to the war effort, reminiscent of the working women and the victory gardens during World War 2  in the US.

Starlink’s value is now well established. Kutkov estimates that there are around 170,000 Starlink terminals in Ukraine, which is constantly increasing. For example:

• The armed forces have around 100,000 terminals provided by various ministries.
• It is common for soldiers to purchase their own terminals. (One retailer has sold almost 2,000 terminals to soldiers so far this year).
• There are thousands of terminals on drone aircraft and boats built by local companies. (One local vendor bought 10,000 terminals for drones).
•  Charity foundations like Serhiy Prytula contribute terminals. (The retail price of a roaming terminal in Ukraine is $613).
• Private donors (including Kutkov) contribute drones and terminals. 
• One service center reported that 90% of the military terminals coming for repairs are privately owned.

Musk’s Grok AI chatbot estimates Starlink’s revenue for Ukraine support is “likely in the ballpark of $150-250 million per year as of now”, a relatively unimportant amount, and about $50 million of that is paid by Poland, which shares a border with Ukraine, has expressed a willingness to seek alternatives to Starlink if necessary and was invaded by Hitler 1939.

Because of recent statements and actions by Donald Trump and Elon Musk, Ukraine and its allies became concerned that Starlink service might possibly be cut off.  

As enumerated in this timeline, Trump has upended the US approach to Ukraine and treated Moscow more as an ally since he became President, culminating in his recent suspension of military aid to and intelligence sharing with Ukraine after he and Vice President Vance berated Zelenskyy in a televised meeting, overstating the amount of US support, falsely claiming that Ukraine had not thanked the US for it’s support and insisting on a “deal” with no security guarantee. 

(Recall that in September 1938, English, French, and Italian leaders signed the Munich Agreement, giving Hitler control of Czechoslovakia in exchange for his promise not to take more land in Europe, and Ukrainians are dying in this war).

Elon Musk has also urged Ukraine to accept peace without a security guarantee to stop the bloodshed. His statement that without Starlink the entire front line would collapse caused concern that he might cut Starlink service off.

Thankfully, Musk has since clarified his position, stating:

"To be extremely clear, no matter how much I disagree with the Ukraine policy, Starlink will never turn off its terminals. Without Starlink, the Ukrainian lines would collapse, as the Russians can jam all other communications! We would never do such a thing or use it as a bargaining chip."

Taking Musk at his word, Starlink service will remain available.

Guowang finally launches ten large production satellites

The first ten Guowang production satellites (source)

In April 2020, The Chinese State Council's executive meeting declared information technology, including satellite Internet,  an important part of the “new technology” and in October, China applied for Guowang, a  12,992-satellite Internet service constellation. Subsequently, a few Guowang test satellites were launched and two other large Chinese constellations were announced, and one, Thousand Sails,  already has 54 satellites in orbit. (Thousand Sails launches have had problems with debris and orbit raising, which attests to the immaturity of the Chinese space industry). Finally, Guowang has launched its first production satellites.

As shown above, ten satellites were launched into orbits about 1,100 kilometers above the Earth, with an inclination of 86.5 degrees. The satellites were launched on a Long March 5B rocket which can carry 23,000 Kg to low-Earth orbit (LEO) and they were stacked in a manner that optimized “the use of vertical and radial space within the payload fairing.” If the rocket was fully loaded, they would be quite large – over 2,000 kg each.

For comparison, Starlink’s current V2-mini satellites are 750-800 kg, and the V3 satellites, which will not begin launching until SpaceX's Starship rockets are in service, are expected to be around 1,900 kg.

Thousand Sail's satellites are smaller than either. They recently launched 18 satellites using a Long March 6A rocket which can carry 4,000 kg to sun-synchronous orbit (SSO). I could not find a mass to LEO for the Long March 6A so I asked four AI services to estimate what a rocket capable of launching 4,000 kg to SSO would be able to launch to LEO. The average estimate was 5,700 kg total or only 317 kg per satellite.

Assuming capability is a function of mass, Guowang satellites will be significantly more powerful than Thousand Sails or Starlink's current satellites. I don't know what those functional differences will be – greater capacity, faster data rates, more power, improved inter-satellite capability, connectivity to 6G devices, etc. For speculation on the features of Starlink's forthcoming V3 satellites see slide 62 in this presentation and this article).

The Guowang constellation will also orbit at a relatively high altitude. The first ten are at 1,100 km and over half the planned constellation will be roughly the same altitude.  Similarly, Thousand Sails' initial 1.296 satellites are orbiting at 1,160 km. While Starlink initially applied to have some 1,100 km satellites, they later lowered their planned orbits. Guowang's relatively high altitude will help compensate for a lack of ground stations.

In an earlier post, I asked whether Guowang could manufacture and launch satellites fast enough to meet Its ITU commitment of launching 10% of the constellation within two years after the bring-into-use (BIU) date 50% by year 5 and all by year 7. Now that production satellites are in orbit and working, I assume the BIU clock has started or will start soon. Given the mass and orbit altitudes of the satellites and Chinese satellite manufacturing and launch capability, they will have a difficult time meeting the ITU deadlines despite new rockets, but in our politically divided world, some nations may ignore those deadlines or Guowang might simply reapply. (It’s even conceivable that Starlink could launch some Guowang satellites since Elon Musk has to please the Chinese government to protect Tesla’s sales and manufacturing in China).

Guowang is late, but the government is committed and the satellites may be comparable to Starlink's V3 satellites. If they can launch the constellation, there will still be a market in serving BRICS and other politically-allied or neutral nations as well as sensitive government and military organizations that are increasingly concerned with Elon Musk’s political ties and mercurial nature. The large mass of their satellites may also result in features that increase their appeal in some applications like backhaul from remote locations that are not reached by fiber. It will be interesting to see what happens when Guowang ITU deadlines expire.

Update 3/8/2025

GuoWang has launched another batch of satellites on a Long March 8A rocket. Space Force cataloged nine objects in orbit, suggesting eight payloads in 862 by 870-kilometer orbits inclined by 50.0 degrees. While I could not find any definitive data online, Grok estimates that a Long March 8A could likely launch 7,200 kg to that orbit, which would imply about 800 kg per satellite, around the mass of the current V2 Starlink satellites and more than double the mass of the Thousand Sails satellites.

Update 5/5/2025

Guowang has launched another batch of satellites on a high-capacity Long March 5B rocket, implying that these are the larger GW2 satellites.

Guowang Launches
Date	Rocket	Satellites
12/16/2024	LM 5B	10
2/11/2025	LM 8A	9?
4/28/2025	LM 5B	10?