Uber-like Content material Supply Community | by Anton Lakhtikov | Feb, 2023

2023-03-15 01:13:16

You probably have many customers and a whole lot of static net content material, you sometimes wish to use a CDN to ship it effectively. Conventional CDN suppliers personal or hire all the needed infrastructure and haven’t any untrusted components of their networks, however this comes with a excessive value for patrons—for instance, AWS expenses between $20 and $87 per TB of site visitors.

Another resolution is to rent a few engineers, hire just a few servers and construct your personal CDN, which might value as little as $2 per TB.

Every of those approaches has shiny and darkish sides. Can we mix the very best components of each worlds: dependable, secure supply with first rate service and low worth?

Fig 1. How Midjourney /think about Farba CDN

At Farba, we’re constructing a zero-cost CDN infrastructure the place all edge servers belong to nameless Friends. A Peer can hire a server, arrange a aggressive worth, and earn cash when serving somebody’s static net content material. Prospects can save as much as 10x on their site visitors payments utilizing our community.

It’s like Uber however for CDN

Utilizing a sharing economic system mannequin forces you to take additional precautions and checks to securely ship static net content material to the top consumer. Let’s examine the way it works in our case.

To make the most of the Farba CDN community, it is advisable to take two steps:

Add the Farba CDN javascript file[1] to your HTML doc:

<script src="https://farbacdn.github.io/farba-public/construct/farbacdn.min.js"></script>

2. Substitute the src attribute of any objects you want to ship by way of our community with the data-src attribute and add the farba class to the tag. For instance, as a substitute of:

<img src="/uploads/FullSky_WMAP_2048W.png"/>

use:

<img class="farba" data-src="/uploads/FullSky_WMAP_2048W.png"/>

There is no such thing as a want to vary your DNS data, and you’ll simply opt-in and out of the Farba CDN community. Moreover, Farba can work on high of any current CDN/Anti-DDoS options. So you possibly can nonetheless be below DDoS safety from a distinguished supplier whereas delivering static net content material from our peer-to-peer community.

In our CDN, we’ve got 4 totally different roles:

Person
Authentic Server (trusted supply)
Balancer (trusted supply)
Peer (untrusted supply)

When the Person opens an internet web page from the Authentic Server, our CDN javascript sends a request to the Balancer. The Balancer then sends again a JSON reply with important data:

The closest location of the file inside the Farba Community
The measurement of the file
The cryptographic digest of the file

Now the CDN script is aware of the brand new location of the requested file and might make an XMLHttpRequest(XHR) obtain name. For the reason that requested file comes from an untrusted supply, the subsequent step is to confirm the integrity of the file. The script calculates the hash sum and compares it to the digest from the JSON reply. If the sums match, the script shows the downloaded file to the Person. If the sums don’t match, the script sends a brand new GET request to the Authentic Server to make sure that the Person receives the file in any case.

Let’s dive into the numbers and see how a lot site visitors one 1 Gbps (devoted, limitless) server can generate in a month.

In idea, with a 1 Gbps server, we are able to serve 128 MB per second. Based mostly on 80% server utilization for 10 hours a day, we estimate that 100 TB of site visitors may be served month-to-month.

128 MB * 80% * 3600 seconds * 10 hours * 30 days = 110592000 MB ≈ 100 TB

We plan to serve every little thing above the purple line utilizing Friends with restricted bandwidth — for instance, a Peer with 1 Gbps and 30 TB of month-to-month site visitors and a small variety of ninety fifth percentile servers belonging to Farba.

This schema will assist us successfully handle day by day peak site visitors and preserve a major reserve of bandwidth.

Our enterprise mannequin is easy: we cost a 20% fee on every transaction between Prospects and Friends.

Let’s study the potential earnings for a Peer within the US and European markets. The Peer can:

Hire a server with 1 Gbps devoted, limitless bandwidth for $200 monthly
Set a worth of $6 per TB
Serve 100 TB of site visitors
Earn $600 ($480 after fee)

Alternatively, the Peer can decide to “earn” site visitors and use it for his or her wants. For instance, if the Peer wants 800 TB of site visitors for his or her mission monthly, they will hire simply one 10 Gbps server and profit from our international community at no additional value.

We’d like each Friends and Prospects to make our community work, however how can we get began with out one or the opposite?

We’ve deployed a number of “pretend” Friends within the US and Europe, which suggests our community is able to serve Prospects from day one.

Because the demand for our providers grows, we’ll open our community for third events and step by step onboard new Friends to make sure all current Friends have sufficient work to do. We purpose to maintain all Friends busy whereas making certain our community has sufficient capability to deal with rising site visitors. Our strategy to accepting new Friends will likely be primarily based on a “first come, first serve” coverage, so you’ll want to be a part of our ready record.

You may view a stay demo on our web site. There, you possibly can open a Developer Console to learn the way the Farba CDN system really works:

https://farbacdn.com/usage/demo/