There has been a surge in the number of CDN services and the use of CDN services in recent months. In this article, we will consider why a certain provider might be a good fit.
Whole site CDN / static website
Whereas static sites, that is, sites with just HTML content, were popular in the ’90s, they are less common today. Therefore, you may need software to generate one for you, using your existing website. Such static site generators are, incidentally, also surging in popularity. Specialist CDNs for static sites, such as Netlify, include built-in tools, although plenty of open source tools are available for different programming languages. Plugins are also available for WordPress.
You can, generally, use almost any CDN for your static site. However, you should consider the reach of the CDN (as always, they should be present where your users are). The features offered by the CDN are also especially important, as, for example, you may want to use your own SSL certificate and control cache expiry times. Aside from Netlify, we have found KeyCDN to be an excellent choice to maximise the use of modern software innovations as well as an extensive network and reasonable prices.
Your CDN should, first and foremost, be present where your users are. Cheap CDNs, like MaxCDN, generally cover locations where hosting is cheaper, to keep costs low. If all of your users are based in the EU and US, this may be ideal, but bear in mind that users (and potentially search rankings) outside these areas – that is, primarily, Australia and Asia, will be limited. Consider whether, for a small percentage cost difference, it is worth using a CDN with better coverage.
Equally, many of the “big name” CDNs, like Edgecast and Akamai, have points of presence in a very large number of locations. The benefit it touted as the content being as close as possible to the user. This is, potentially, correct. However, bear in mind that if the POP does not have your content in its cache, which is more likely on a larger network, it has to fetch it, usually from your server, before delivering it. This is far from ideal. To counterbalance this, some such CDNs offer their own storage facility, that should be considered alongside the CDN offer.
Neither Akamai not Edgecast (now Verizon) sell directly to small businesses. Akamai’s CDN is available via Rackspace and Edgecast is available via Speedy Rails. These resellers offer access to the same network although the level of control is sometimes limited, and in particular, there may be significant additional costs for certain features that are free with smaller CDNs.
Features should be considered carefully. There are numerous software innovations that, alongside good network coverage, are a significant benefit:
One of the most popular articles on our blog is an article dispelling common myths around SSL certificates. Let’s Encrypt gained a lot of attention after the article was written. Let’s Encrypt is a radically new way of getting an SSL certificate that is primarily popular because it’s free. The motivation is supposedly that, in 2015, there is really no reason not to use HTTPS. The overhead was considerable in the 90s but today, in most circumstances there is no perceivable difference. With recent revelations about ISP and government spying, other concerns about privacy and a spate of large hacks, there is a potentially lot to be gained. Google is also prioritising websites using HTTPS in its rankings and, more recently, in Chrome.
The cost to issue SSL certificates is generally very low so it is possible to offer them for nothing and rely on advertising or sponsorship. Let’s Encrypt is sponsored by several recognised names including Mozilla, Cisco and Facebook. It has also recently left beta, meaning that they believe that it’s stable enough for normal use, which has also been our experience.
Let’s Encrypt vs. the competition
Most SSL issuers have a set way of issuing certificates. For certificates other than EV (extended validation, “green bar”), you receive an email at a recognised email address on the domain that you want to secure. This proves that you control the domain and allows them to fulfil their obligations. Comodo has also added some other options such as creating a DNS record or uploading a file to your webspace. In all cases, when you’ve done this, you get the certificate, for at least one year.
The certificates aren’t usually recalled except under extreme circumstances (e.g. if you bought from a reseller who didn’t pay their bill) although they can, hypothetically, be recalled in most cases using OCSP, a modern standard, also aggressively supported by Google, that allows the issuer to revoke it in a way that is obvious to most users.
To use Let’s Encrypt, you or your hosting company or server administrator must install some software on the server that automates the Comodo-style HTML file upload process. Every so often, it speaks to Let’s Encrypt to get a new HTML file and places it in your web root. Let’s Encrypt sees it and issues a new certificate that is good for another (in our experience) 90 days. The impressive feat here is that once the software is installed, it’s all automatic. The down side is that the software must be installed and maintained, although it is fairly easy.
Those who use cPanel can easily install a plugin (that works well in our experience) to easily add and remove certificates to/from websites without dealing with an issuer or reseller. A web hosting provider with hundreds of accounts can save their users a lot of expense and time with this plugin.
Why you might not use Let’s Encrypt
There are relatively few reasons why one should not use it. The security is the same, it costs nothing and the issuance process is usually easier. If your hosting company doesn’t allow you to install the software or doesn’t support it themselves, for now, you’ll have to buy certificates the old way. Equally, if you have a lot of subdomains to secure or want a “green bar”, you might still opt for a wildcard or EV certificate since Let’s Encrypt don’t issue them. I’ve yet to see any impartial numbers on how EV certificates and site seals impact sales – I would guess the impact is very minimal in percentage terms. However, for a busy e-commerce website, it is probably worth the £30-100 to buy an EV certificate even if the percentage effect on conversions is very small.
Overall, the author is glad that the days of expensive SSL certificates are coming to a close. It was an industry that we could do without and Let’s Encrypt have had a substantial impact on way SSL certificates will be issued from now on.
If, like us, you manage a lot of servers, it can be difficult to organise them. Some time ago, we explored a few options and settled on Ezeelogin. Ezeelogin is one of very few products that provides an easy to use SSH gateway. In our case, however, the problem we needed to solve was very simple: to allow trusted staff members easy access to an evolving catalogue of servers.
Today, we are open sourcing the custom built SSH gateway that we use in-house. It uses a MySQL database to store server groups, servers and users (there is no web interface for this yet but phpMyAdmin would do everything necessary). When a user logs in, it looks up which groups that user can see. The user selects a group and it displays all of the servers in that group. The user then selects a server and it logs them in.
Authentication between the user and gateway is handled in the normal way – they have their own system user and can use a password or a key – whatever is set is sshd_config. Authentication between the gateway and the server is with an SSH keypair that is shared by all users but can only be seen by root (on a properly configured server).
To reiterate, whereas some products have focused very heavily on security, we have a number of security policies within our company that reduce the need for the gateway to be anything more than a tool for convenience. That said, I recommend the following steps to secure the gateway:
Download it on GitHub
When new users are added, they must have access to the wheel group and therefore, sudo. This is to access the shared key. You can of course copy keys, use individual keys or set up password authentication if you wish – but users should not be able to access the normal shell anyway. Each user’s shell (in /etc/passwd) should be /sbin/gwshell, which means that they see the gateway rather than a normal shell when they log in. All of this is handled in gwuseradd if you choose to use it: “gwuseradd [username]”.
Usernames in /etc/passwd need to match usernames in the database. If there is no match, they won’t be able to access any servers. Groups in the “users” table is comma-separated so, if you want to give a user access to groups 1 and 3, enter “1,3”.
Support, licence etc.
The software is MIT licensed. We hope it is convenient for you as it is for us. You may use it free of charge, at entirely your own risk. Because it is free, if you need support from us, obviously, it will be chargeable. It is pretty easy to use, though.