SNI progressive enhancment
Today marks another big milestone in the availabilibty of ubuquitous SSL encryption: The «Let’s Encrypt» project got their cross-signature, so come a few more weeks, they will be ready for the public to use.
However, with an unlimited amount of available free SSL certificates, we get another problem: Because back in the day nobody thought about name based virtual hosting, the initial implementation of SSL didn’t support the client telling the server what host it’s trying to connect to. This means that the server didn’t know what certificate to present when multiple host names were to be used for the same address.
This meant that for every site you wanted to offer over SSL, you needed an IP address, which are harder to get as time moves on and we’re running out of them.
«SNI» is a protocol extension that allows the client to tell the server the host-name it’s connecting to, so the server can chose the correct certificate to serve. This fixes above issue and finally allows virtual hosting based on the host name even over SSL.
Unfortunately, SNI isn’t as widely supported as we’d like: Older Android devices and all IEs under Windows XP (which still is a sizeable portion of our users) dont’ support SNI.
What’s also tricky is that you don’t know a client doesn’t support SNI until it’s too late: They connect to your port 443, don’t send a host name and now the server needs to a) answer and b) send a server certificate. So unless the client accidentally hit the correct host name, the client will get a certificate mismatch and it will thus display the usual SSL error message.
This is of course not very good UX as you don’t even get to tell the user what’s wrong before they see the browser-specific error message.
However, I still want to support SSL for all my sites wherever I can. If I could have non-SNI-supporting clients on an unencrypted site and then adding encryption only if they support SNI, then encryption would become a progressive enhancement. The sites I’m dealing with aren’t that far in the «needs encryption» territory, so offering encryption only for good (read: non-outdated) browsers is a viable option, especially as I want to offer this for free for the sites I’m hosting and I only have so many IP addresses at my disposal right now.
Generally, the advice to do that is to do user agent sniffing but that’s error-prone. I’d much rather feature detect.
So after a bit of thinking, I came up with this (it requires JS though):
- Over port 80, serve the normal site unencrypted instead of just redirecting to https.
- On that regular site do a jsonp request for some beacon file on your site over https.
- If that beacon loads properly, then your client is obviously SNI compliant, so redirect to the https version of your site using JS.
- If the beacon doesn’t load, then the browser probably doesn’t support SNI, so keep them on the unencrypted page. If you want to, you can set a cookie to prevent further probing on subsequent requests.
- On port 443, serve a HSTS header, so next time the browser visits, they’ll use HTTPS from the start.
IE8 will still show the page correctly but also show a warning that it has blocked content for your own security, so you might want to immediately redirect again (with the cookie set) in order to get rid of the warning.
Contrary to the normal immediate redirect to HTTPS, this means that the first page-view even of compliant browsers will be unencrypted, so absolutely make sure that you serve all your cookies with the
Maybe you can come up with some crazy hack using frames, but this method seems to be the cleanest.Read on →
IPv6 in production
Yesterday, I talked about why we need IPv6 and to make that actually happend, I decided to do my part and make sure that all of our infrastructure is available over IPv6.
Here’s a story of how that went:
First was to request an IPv6 allocation by our hosting provider: Thankfully our contract with them included a /64, but it was never enabled and when I asked for it, they initially tried to bill us CHF 12/mt extra, but after pointing them to the contract, they started to make IPv6 happen.
That this still took them multiple days to do was a pointer to me that they were not ready at all and by asking, I was forcing them into readyness. I think I have done a good deed there.
Before doing anything else, I made sure that our DNS servers are accessible over IPv6 and that IPv6 glue records existed for them.
We’re using PowerDNS, so actually supporting IPv6 connectivity was trivial, though there was a bit of tweaking needed to tell it about what interface to use for outgoing zone transfers.
Creating the glue records for the DNS servers was trivial too - nic.ch has a nice UI to handle the glue records. I’ve already had IPv4 glue records, so all I had to do was to add the V6 addresses.
Making our web properties available over IPv6 was trivial. All I had to do was to assign an IPv6 address to our frontend load balancer.
I did not change any of the backend network though. That’s still running IPv4 and it will probably for a long time to come as I have already carefully allocated addresses, configured DHCP and I even know IP addresses by heart. No need to change this.
I had to update the web application itself a tiny bit in order to copy with a
REMOTE_ADDR that didn’t quite look the same any more though:
- there were places where we are putting the remote address into the database. Thankfully, we are using PostgreSQL whose native
inettype (it even supports handy type specific operators) supports IPv6 since practically forever. If you’re using another database and you’re sotoring the address in a
VARCHAR, be prepared to lengthen the columns as IPv6 addreses are much longer.
- There were some places where we were using CIDR matching for some privileged API calls we are allowing from the internal network. Of course, because I haven’t changed the internal network, no code change was strictly needed, but I have updated the code (and unit tests) to deal with IPv6 too.
The last step was to add the AAAA record for our load balancer.
From that moment on, our web properties were available via IPv6 and while there’s not a lot of traffic from Switzerland, over in Germany, about 30% of all requests are happening over IPv6.
Of the bunch, dealing with email was the most complicated step. Not so much for enabling IPv6 support in the MTA as that was supported since forever (we’re using Exim (warning: very old post)).
The difficulty lied in getting everything else to work smoothly though - mostly in regards to SPAM filtering:
- Many RBLs don’t support IPv6, so I had to make sure we weren’t accidentally treating all mail delivered to us over IPv6 as spam.
- If you want to have any chance at your mail being accepted by remote parties, then you must have a valid PTR record for your mail server. This meant getting reverse DNS to work right for IPv6.
- Of course you also need to update the SPF record now that you are sending email over IPv6.
The PTR record was actually the crux of the matter.
In IPv4, it’s inpractical or even impossible to get a reverse delegation for anything smaller than a /24, because of the way how reverse lookup works in DNS. There was RFC 2317 but that was just too much hassle for most ISPs to implement.
So the process normally was to let the ISP handle the few PTR records you wanted.
This changes with IPv6 in two ways: As the allocation is mostly fixed to a /64 or larger and because there are so many IPv6 addreses to allow splitting networks at byte boundaries without being stingy, it is trivially easy to do proper reverse delegation to customers.
And because there are so many addresses available for a customer (a /64 allocation is enough addresses to cover 2^32 whole internets), reverse delegation is the only way to make good use of all these addresses.
This is where I hit my next roadblock with the ISP though.
They were not at all set up for proper reverse delegation - the support ticket I have opened in November of 2014 took over 6 months to finally get closed in May of this year.
As an aside: This was a professional colocation provider for business customers that was, in 2014, not prepared to even just hand out IPv6 addresses and who required 6 months to get reverse delegation to work.
My awesome ISP was handing out IPv6 addresses since the late 90ies and they offer reverse delgation for free to anybody who asks. As a matter of fact, it was them to ask me whether I wanted a reverse delegation last year when I signed up with them.
Of course I said yes :-)
This brought me to the paradoxical situation of having a fully working IPv6 setup at home while I had to wait for 6 months for my commercial business ISP to get there.
it’s done now
So after spending about 2 days learning about IPv6, after spending about 2 days updating our application, after spending one day convincing our ISP to give us the IPv6 allocation they promised in the contract and after waiting 6 months for the reverse delegation, I can finally say that all our services are now accessible via IPv6.
Here are the headers of the very first Email we’ve transmitted via IPv6
And here’s the achievement badge I waited so patiently (because of the PTR delegation) to finally earn 🎉
I can’t wait for the accompanying T-Shirt to arrive 😃Read on →
Why we need IPv6
As we are running out of IPv4 network addresses (and yes, we are), there’s only two possible future scenarios and one of the two, most people are not going to like at all.
As IP addresses get more and more scarce, things will start to suck for both clients and content providers.
As more and more clients connect, carrier grade NAT will become the norm. NAT already sucks, but at least you get to control it and using NAT-PMP or UPnP, applications in your network get some control over being able to accept incoming connections.
Carrier Grade NAT is different. That’s NAT being done on the ISPs end, so you don’t get to open ports at all. This will affect gaming performance, it will affect your ability to use VoIP clients and of course file sharing clients.
For content providers on the other hand, it will become more and more difficult to get the public IP addresses needed for them to be able to actually provide content.
Back in the day, if you wanted to launch a service, you would just do it. No need to ask anybody for permission. But in the future, as addresses become scarce and controlled by big ISPs which are also acting as content provider, the ISPs become the gatekeepers for new services.
Either you do something they like you to be doing, or you don’t get an address: As there will be way more content providers fighing over addresses than there will be addresses available, it’s easy for them to be picky.
Old companies who still have addresses of course are not affected, but competing against them will become hard or even impossible.
More power to the ISPs and no competition for existing content providing services both are very good things for players already in the game, so that’s certainly a possible future they are looking forward to.
If we want to prevent this possible future from becoming reality, we need a way out. IPv4 is draining up. IPv6 exists for a long time, but people are reluctant to upgrade their infrastructure.
It’s a vicious cycle: People don’t upgrade their infrastructure to IPv6 because nobody is using IPv6 and nobody is using IPv6 because there’s nothing to be gained from using IPv6.
If we want to keep the internet as an open medium, we need to break the cycle. Everybody needs to work together to provide services over IPv6, to the point of even offering services over IPv6 exclusively.
Only then can we start to build pressure for ISPs to support IPv6 on their end.
If you are a content provider, ask your ISP for IPv6 support and start offering your content over IPv6. If you are an end user, pressure your ISP to offer IPv6 connectivity.
Knowing this, even one year ago, after getting motivated by my awesome ISP who offered IPv6 connectivity ever since, I started to get our commercial infrastructure up to speed.
Read on to learn how that went.Read on →
The Future of the JRPG genre
After an underwhelming false start with Xenoblade Chronicles back when the game came out, the re-release on the 3DS made my give it another try and now that I’m nearly through with the game (just beat the 3rd last main quest boss), I feel compelled to write my first game review after many years of non-gaming content here.
«Review» might not be the entirely correct term though as this article is about to explain why I personally believe Xenoblade to be one of the best instances of the JPRG genre and might actually be very high up there in my list of all-time favorite games.
But first, let’s talk about what’s not so good at the game and why I nearly have missed this awesome game: If I had to list the shortcomings in this masterpiece, it would be the UI design of the side-questing system and the very, very slow start of the story.
First the story: After maybe an hour of play time, the player is inclined to think to have been thrown into the usual revenge plot, this time about a fight against machine based life-forms, but a simple revenge-plot none the less. Also, to be honest, it’s not even a really interesting revenge-plot. It feels predictable and not at all like what we’re usually used to from the genre.
Once you reach the half-time mark of the game, the subtle hints that the game’s dropping on you before that start to become less and less subtle, revealing to the player that they got it all wrong.
The mission of the game changes completely to the point of even completely changing whom you are fighting against and turning around many things you’ve taken for granted for the first half.
This is some of the most impressive story-development I’ve seen so far and also came as a complete surprise to me.
So what felt like the biggest shortcoming of the game (lackluster story) suddenly turned into one of its strongest points.
«Other games of the genre also did this» you might think as you compare this to Final Fantasy XII, but where that game unfortunately never really takes off nor adds any bigger plot-twists, the thing that Xenoblade does after the half-time marker is simply mind-blowing to the point of me refusing to post any spoilers even though the game is quite old by now.
So we have a game that gets amazing after 20-40 hours (depending on how you deal with the side-quests). What’s holding us over until then?
The answer to that question is the reason why I think that Xenoblade is one of the best JRPGs so far: What’s holding us over in the first 40 hours of the game is, you know, gameplay.
The battle system feels like it has been lifted from current MMORPGs (I’m mostly referring to World of Warcraft here as that’s the one I know best), though while it has been scaled down in sheer amount of skills, the abilities themselves have been much better balanced between the characters, which of course is possible in a single-player game.
The game’s affinity system also greatly incentivises the player to switch their party around as they play the game. This works really well when you consider the different play styles offered by the various characters. A tank plays differently from DPS which plays differently from the (unfortunately only one) healer.
But even between members of the same class there are differences in play style leading to a huge variety for players.
This is the first JRPG where I’m actually looking forward to combat - it’s that entertaining.
While the combat sometimes can be a bit difficult, especially because randomness still plays a huge part, it’s refreshing to see that the game doesn’t punish you at all for failing: If you die you just respawn at the last waypoint and usually there’s one of these right in front of the boss.
Even better, normally, the fight just starts again, skipping all introductory cutscenes. And even if there still is some cut-scenes not skipped automatically: The game always allows cutscenes to be skipped.
This makes a lot of sense, because combat is actually so much fun that there’s considerable replay-value to the game which gets much enforced by skippable cutscenes, though some of them you would never ever in your life want to skip - they are so good (you know which ones I’m referring to).
Combat is only one half of the gameplay, the other is exploration: The world of the game is huge and for the first time ever in a JPRG, the simple rule of «you can see it, you can go there» applies. For the first time ever, the huge world is yours to explore and to enjoy.
Never have I seen such variety in locations, especially, again, in the second half of the game which I really don’t want to spoil here.
Which brings us to the side-quests: Imagine that you have a quest-log like you’re used to from MMORPGs with about the same style of quests: Find this item, kill these normal mobs, kill that elite mob, talk to that other guy - you know the drill.
The non-unique and somewhat random dialog lines between the characters as they accept these side-quests break the immersion a bit.
But the one big thing that’s really annoying about the side-quests is discoverability: As a player you often have no idea where to go due to the vague quest texts and, worse, many (most) quests are hidden and only become available after you trigger some event or you talk to the correct (seemingly unrelated) NPC.
While I can understand the former issue (vague quest descriptions) from a game-play perspective, the latter is inexcusable, especially as the leveling curve of the game and the affinity system both really are designed around you actually doing these side-quests.
It’s unfair and annoying that playing hide-and seek for hours is basically a fixed requirement to having a chance at beating the game. This feels like a useless prolonging of the existing game for no reason but to, you know, prolong the game.
Thankfully though, by now, the Wiki exists, so whether you’re on the Wii or the 3DS, just have an iPad or Laptop close to you as you do the side-questy parts of the game.
Once you’re willing to live with this issue, then the absolutely amazing gameplay comes into effect again: Because exploration is so much fun, because the battle system is so much fun, then suddenly the side-quests become fun too, once you remove the annoying hide-and-seek aspect.
After all, it’s the perfect excuse to do more of what you enjoy the most: Playing the game.
This is why I strongly believe that this game would have been so much better with a more modern quest-log system: Don’t hide (most of the) quests! Be precise in explaining where to find stuff! You don’t have to artificially prolong the game: Even when you know where to go (I did thanks to the Wiki), there’s still more than 100 hours of entertainment there to be had.
The last thing about quests: Some of the quests require you to find rare items which to get you have a random chance by collecting «item orbs» spread all over the map. This is of course another nice way to encourage exploration.
But I see no reason why the drop rate must be random, especially as respawning the item orbs either requires you to wait 10 to 30 minutes or, saving and reloading the game.
If you want to encourage exploration, hide the orbs! There’s so much content in this game that aritifically prolonging it with annyoing saving and reloading escapades is completely unnecessary.
At least, the amount of grinding required isn’t so bad to the point of being absolutely bearable for me and I have nearly zero patience for grinding.
Don’t get me wrong though: Yes, these artificial time-sinks were annoying (and frankly 100% unneeded), but because the actual gameplay is so much fun, I didn’t really mind them that much.
Finally, there are some technical issues which I don’t really mind that much however: Faces of characters look flat and blurry which is very noticable in the cut-scenes which are all rendered by the engine itself (which is a very good thing).
Especially on the 3DS the low resolution of the game is felt badly (the 3DS is much worse than the Wii to the point of objects sometimes being invisible) and there’s some objects popping into view at times. This is mostly a limitation of the hardware which just doesn’t play well with the huge open world, so I can totally live with it. It only minimally affects my immersion into the game.
If you ask me what is the preferred platform to play this on, I would point at the Wii version though, of course, it’ll be very hard to get the game at this point in time (no. you can’t have my copy).
So after all of this, here’s a list of the unique features of this game it has over all other members of its genre:
- Huge world that can be explored completely. No narrow hallways but just huge open maps.
- Absolutely amazing battle system that goes far beyond of the usual «select some action from this text-based menu»
- Skippable cutscenes which together with the battle system make for a high replayability
- Many different playable characters with different play styles
- Great music by the god-like Mr. Mitsuda
- A very, very interesting story once you reach the mid-point of the game
- Very believable characters and very good character development
- Some of the best cutscene direction I have ever seen in my life - again, mostly after the half-time mark (you people who played the game know which particular one I’m talking about - still sends shivers down my spine).
My wishes for the future
The game is nearly perfect in my opinion, but there are two things I think would be great to be fixed in the successor or any other games taking their inspiration from Xenoblade:
First, please fix the quest log and bring it to the current decade of what we’re used to from MMORPGs (where you lifted the quest design off to begin with): Show us where to get the quests, show us where to do them.
Second, and this one is even bigger in my opinion: Please be more considerate in how you represent women in the game. Yes, the most bad-ass characters in the game are women (again, I can’t spoil anything here). Yes, there’s a lot of depth to the characters of women in this game and they are certainly not just there for show but are actually instrumental to the overall story development (again, second part).
But why does most of the equipment for the healer in the game have to be practically underwear? Do you really need to spend CPU resources on (overblown) breast physics when you render everybodies faces blurry and flat?
Wouldn’t it be much better for the story and the immersion if the faces looked better at the cost of some (overblown) jiggling?
Do you really have to constantly show close-ups of way too big breasts of one party member? This is frankly distracting from what is going on in the game.
I don’t care about cultural differences: You managed to design very believable and bad-ass women into your game. Why do you have to diminish this by turning them into a piece of furniture to look at? They absolutely stand on their own with their abilities and their character progression.
It is the year 2015. We can do better than this (though, of course, the world was different in 2010 when the game initially came out).
All of that aside: Because of the amazing game play, because of the mind-blowing story, because of the mind-blowing custscene-direction and because of the huge world that’s all but narrow passages, I love this game more than many others.
I think that this is the first time that the JRPG game really has moved forward in about a decade and I would definitely like to see more games ripping off the good aspects of Xenoblade (well - basically everything).
As such I’m very much looking forward for the games successor to become available here in Europe (it has just come out in Japan and my Japanese still is practically non-existent) and I know for a fact that I’m going to play it a lot, especially as I now know to be patience with the side-quests.Read on →