11 ms·
Astranis emerges from stealth with new satellite tech for connecting the world
- nappy 9y agoIsn't latency a major issue for connectivity with satellites in geosynchronous orbit? I'm curious what their approach is here, either technically or what customer use cases they are targeting.
- gedmark 9y agoThe distance to GEO does add some latency due to the distance, that’s the main trade off. What we found in studying this problem for a long time was that 95% of internet traffic isn’t latency sensitive— CDN traffic, video streaming, audio streaming, file downloads, social media posts, etc. The bandwidth crunch is a huge problem to solve but we realized there is low hanging fruit here that we can go after by putting satellites one at a time in GEO and putting a dent in it immediately. vs LEO constellations where you have to put up hundred of satellites (at a cost of billions of dollars) just to get started.
- p1necone 9y ago95% of traffic != 95% of value.
- shaklee3 9y agoYou're right. It's higher. Close to 100% of the valuable traffic is not latency sensitive.
- paulsutter 9y agoHow do you plan to compete with SpaceX once they start offering low latency service everywhere? All interactive traffic is latency sensitive (have built middleboxes to improve latency issues with tcp and other protocols)
- jandrese 9y agoI'd take SpaceX's latency claims with a big grain of salt. They'll only be true if you're in close geographic proximity to one of their ground stations. Once you're routing packets between satellites to get to a ground station all bets are off.
- bryananderson 9y agoThe SpaceX ground stations are meant to be consumer owned (about the size of a pizza box).
- dfox 9y agoThere is a difference between the CPE (what you use to get the service) and what SpaceX uses to sink your traffic into the global internet. And in fact there is exactly zero incentive for somebody other than SpaceX to run the ground stations. On the other hand it is completely possible that SpaceX's ground stations will use HW that is similar to their CPE box and thus they can build ridiculous amount of such ground stations (ie. at every IXP or so, althought the "lightweith non-IP transport" proclamation somehow precludes doing that)
- jandrese 9y agoThat would be an interesting model for the ground stations. Everybody else builds large and capable ground stations with big dishes. Iridium for example provides global phone and slow data coverage using only one public ground station, but also uses a completely different band to talk with the ground stations vs. the handhelds.
- planteen 9y agoIridium used to have multiple gateways. I think Arizona, Italy, Middle East, and Asia. Do they only use Arizona now?
- 9y ago
- jandrese 9y agoAudio streaming not including voice calls I assume, because those are absolutely latency sensitive. Are your terminals going to include TCP Performance Enhancing Proxies (PEPs)? The TCP three way handshake followed by the TLS handshake makes it kind of painful to browse on an unaccelerated network with a GEO hop. And this is before you get to the latency from the ground station to the website. The problem gets even worse in Web2.0 world where everything is running off of tiny queries that the web app developers assume will be back in 50ms or so. TCP PEPs can only do so much too (cutting down on the roundtrips and ramping up the window size more quickly), eventually you hit the hard limits of physics.
- dfox 9y agoFrom my experience it is not so hard to build completely terrestrial links that have latency that is large enough such that TCP works (althought it should not), but TLS handshake will timeout. For GEO links you will get exactly this behavior by using BGAN terminal over Bluetooth DUN profile (BT adds enough latency for this to happen).
- jandrese 9y agoThe only time I've seen a terrestrial link with a latency so bad that TCP couldn't be established it also required you to install a poorly behaved app that reduced Window's TCP retransmit limit to 1 (from 3). TLS setups however as you note are a whole new ball of wax, especially if the link has a bit of loss to go along with the latency.
- PaulHoule 9y agoI am skeptical of that analysis. I have worked over ssh over internet connections with satellite-class latency and I can say it is painful. (Emacs shell mode can help) You probably think that 'the web' is a high latency application. It probably should be, and maybe it was in 2000. Since then, web developers have gotten into the habit of using AJAX indiscriminately, plus they feel pressured to add features such as customized fonts, advertising, third party tracking, etc. I am not sure if CDN is really a net positive when a web site might need to do 30 DNS lookups because it uses 30 CDNs. It just takes one of those lookups to be slow to obliterate the savings from the CDN. CDNs might help with the median, even the average load time, but I am not sure they help the 95% load time which is what causes customer pain. Add up all those round trips and the overhead of access control (maybe those patents on slotted ALOHA for satellite applications have expired by now) and you are talking upwards of 0.5 sec and it doesn't take many round trips for that 0.5 sec to turn into 5 to 10 seconds. Worst thing is that people who are developing locally or from places with fast connections to the data center will think these apps are really fast.
- gedmark 9y agoAgree on the AJAX calls. Modern web apps are a mess. Thankfully mobile apps are built quite differently, so that's an improvement. And the biggest potential market out there to serve is new users that will be coming online for the first time mobile-first.
- shaklee3 9y agoSSH is not a typical use case. He said 90-95% of traffic isn't latency sensitive, and yours isn't in the majority.
- deleted 9y ago[deleted]
- mirimir 9y agoThat was my first question too, once I saw that you'll be using geostationary satellites. But yes, I get your argument about acceptable latency vs cost. Sometimes I use Tor via nested VPN chains, for decent anonymity, and total rtt can be hundreds of ms or more. Web browsing, chats, downloads, and even ssh sessions, are all workable. And if push to talk is acceptable, even VoIP is workable at 1-2 sec rtt.
- gedmark 9y agoHi everyone, I’m one of the cofounders of Astranis (YC W16). Thanks for taking the time to read about what we’re doing and happy answer any questions.
- caio1982 9y agoWith what rocket system do you plan to launch these sats? Which company will launch and which will assemble them (often these are different ones)?
- gedmark 9y agoWe're compatible with all the major launch vehicle families-- SpaceX Falcon 9, Atlas V, Ariane 5, and some of the other foreign launchers. Part of the great thing about where things are in the industry today is that ride shares for micro-satellites (where you fly as a piggy-back alongside a traditional satellite) are pretty much a solved problem.
- caio1982 9y agoWhy do you think this pin-point for-hire internet sat service is better than a constellation? Is it because you can profit right away without an initial setup cost of the constellation? But in the long run the constellation pays off and might drive you out of business, right?
- PaulHoule 9y agoIt may or may not. If you think there is a rural/urban problem with optic fiber, you are jumping from the frying pan to the fire with LEO satellite constellations. That's because an LEO satellite constellation has to cover the whole world (or almost all of it) to be able to cover any inhabited area at all. Thus it has to cover oceans, large roadless areas, deserts, mountains, etc. At least with optic fiber you only have to cover roads. Note that high density areas can cause trouble on the other side -- you need to support the highest density worldwide that you support anywhere. Note that users in a place like New York City will generate noise affecting satellites 1000+ miles away, so if you don't ban people setting up accounts in dense areas, it will have to be priced so high that people with a lot of money looking for a backup connection will be priced out. I am highly skeptical that the economics can work out for an LEO constellation.
- CamperBob2 9y agoArticle is completely unreadable on a phone, due to a giant junk-quality ad that elbows out the content. Anyone got a better link?
- consciouskernel 9y agoThere's a reason that no other company tries to use geosynchronous orbit. Stationary orbit is at a distance of 35800 km above sea level, which implies a one way latency of 110 ms based off the speed of light. Since any request from a user requires a total of 2 round way trips (one for request, one for response), the minimum latency for a request is 440 ms. Avg latency with fiber is something like 30-60 ms, so we can assume an average request with Astranis will have ~500 latency. Most modern webpages will not be able to support such latency. Astranis will need to essentially cache webpages on demand and deliver them to the end user as a fully rendered page, which will introduce security headaches. I don't see why Astranis chose this vs a lower orbit.
- wmf 9y agoNo other company... like HughesNet, ViaSat, Inmarsat, Intelsat, etc. Maybe you were led astray by this terrible TechCrunch article.
- jmagoon 9y agoSeriously. Ever used internet on an airplane? You're using one of those companies geostationary satellites. The article is ridiculous.
- blackguardx 9y agoNot necessarily. GoGo Inflight uses ground links for domestic US flights.
- bmcooley 9y agoAnd they're being dropped in favor of geosynchronous providers.
- blackguardx 9y agoI don't know much about their market. A friend of mine works there though, and he said they are growing.
- tomrod 9y agoI'm excited for a (one day?) IPO!
- mmmBacon 9y agoHow is 10Gb/s achieved and how reliable is that BW in the presence weather? What is the practical coverage area of the satellite and what would the typical user BW be on a clear day? How would the BW change on a rainy day?
- nkoren 9y agoMeta-comment: I haven't seen this noted elsewhere, but there's been a very sudden and significant acceleration in the pace of space launch. So far there have been 22 launches this year, which is about double the pace of last year. And there are more than 180 launches planned -- again, double the pace of last year. The most launches ever to occur in a single year was 139 -- during the height of the space race in 1967. Although many of this year's planned launches will undoubtedly slip into next year, we're quite likely to set an all-time record: https://en.wikipedia.org/wiki/Timeline_of_spaceflight https://en.wikipedia.org/wiki/Timeline_of_spaceflight Also notable is the fact that of the 22 launches this year, three have been the debuts of entirely new vehicles, two of which were entirely privately funded. There are likely to be several more private launch vehicle debuts this year. This is a really significant shift for what had long been a moribund industry, and a lot of complementary innovations will be able to piggyback onto this momentum.
- wastedhours 9y agoReally exciting, but have the regulations of what "stuff" we're putting up/leaving up there moved as fast?
- nkoren 9y agoFor the most part, yes. Changes in the regulatory system have been one of the critical enablers for this during the last decade. The key area where the regulations haven't particularly kept pace is in extra-terrestrial property rights.
- guhcampos 9y agoI don't see the novelty on this at all. Geostationary satellites are pretty much the standard for satellite internet for years. I had a broadband connection like that on my first job, 15 years ago. It's off course very welcome if they can get higher transfer speeds, cleaner and lighter satellites and newer technologies to the mix, but that's it. The biggest problem with satellite internet: the latency, is not going to be solved. Which is fine, I must say, since they are in the business of bringing Internet to where there's none. But these new Internet users will arrive without access to the Internet's most incredible features, such as real time voice and video communication, interactive website experiences and online gamming.
- black_puppydog 9y agoFunny how you say those are the most incredible features. For me (and obviously this is personal preference, so please don't take offence) these are "nice to have" features. What I'm really after are (and have been, since I kinda grew out of FPS games) * google/$INFORMATION * Wikipedia * podcasts * spotify/torrent/$MUSIC * blogs/twitter * youtube/netflix/torrent/$VIDEO pretty much in that order. None of which would be a problem on satellite (albeit less convenient) but would make a day/night difference for me. As for the "interactive website experiences", that's usually the part I like the least about a website, which is why I use uMatrix most of the time, making pages more readable (or, depending on the JS affinity of the people making them, completely unreadable)
- gedmark 9y agoMost large GEO's today still use purely analog repeaters. Having a true digital payload where we're doing digital signal processing on board the satellite is a significant step forward. To get to the lower costs that we're aiming for, going to software defined radios was a necessary step. That's because it gives us the ability to build many satellites that are as identical as possible without hardwiring in the specific frequencies like they do with analog satellites today. It's hard to overstate the importance of that technology for what we're doing and the low cost targets we need to hit to get unconnected people online.