At the end of Q3 2023, Backblaze was monitoring 263,992 hard disk drives (HDDs) and solid state drives (SSDs) in our data centers around the world. We’ve reported on those drives for many years. But, all the data on those drives needs to somehow get from your devices to our storage servers. You might be wondering, “How does that happen?” and “Where does that happen?” Or, more likely, “How fast does that happen?”
These are all questions we want to start to answer.
Welcome to our new Backblaze Network Stats series, where we’ll explore the world of network connectivity and how we better serve our customers, partners, and the internet community at large. We hope to share our challenges, initiatives, and engineering perspective as we build the open cloud with our Partners.
In this first post, we will explore two issues: how we connect our network with the internet and the distribution of our peering traffic. As we expand this series, we hope to capture and share more metrics and insights.
Nice to Meet You; I’m Brent
Since this is the first time you’re hearing from me, I thought I should introduce myself. I’m a Senior Network Engineer here at Backblaze. The Network Engineering group is responsible for ensuring the reliability, capacity, and security of network traffic.
My interest in computer networking began in my childhood when I first persuaded my father to upgrade our analog modem to an ISDN line by providing a financial comparison of time sink due to large download times I was conducting (nothing like using all the family dial-up time to download multi-megabyte SimCity 2000 and Doom customizations). Needless to say, I’m still interested in those same types of networking metrics, and that’s why I’m here sharing them with you at Backblaze.
First, Some Networking Basics
If you’ve ever heard folks joke about the internet being a series of tubes, well, it may be widely mocked, but it’s not entirely wrong. The internet as we know it is fundamentally a complex network of all the computers on the planet. Whenever we’re typing in an internet address into a web browser, we’re basically giving our computer the address of a computer (or server, etc.) to locate, and that computer will hopefully display data to you that it’s storing.
Of course, it’s not a free-for-all. Internet protocols like TLS/SSL are the boundaries that set the rules for how computers communicate, and networks allow different levels of access to outsiders. Internet service providers (ISPs) are defined and regulated, and we’ll outline some of those roles and how Backblaze interacts with them below. But, all that communication between computers has to be powered by hardware, which is why, at one point, we actually had to solve the problem of sharks attacking the internet. Good news: since 2006, sharks have accounted for less than one percent of fiber optic cable attacks.
Wireless internet has largely made this connectivity invisible to consumers, but the job of Wi-Fi is to broadcast a short-range network that connects you to this series of cables and “tubes.” That’s why when you’re transmitting or storing larger amounts of data, you typically get better speeds when you use a wired connection. (A good consumer example: setting up NAS devices works better with an ethernet cable.)
When you’re talking about storing and serving petabytes of data for a myriad of use cases, then you have to create and use different networks to connect to the internet effectively. Think of it like water: both a fire hose and your faucet are connected to utility lines, but they have to move different amounts of water, so they have different kinds of connections to the main utility.
And, that brings us to peering, the different levels of internet service providers, and many, many more things that Backblaze Network Engineers deal with from both a hardware and a software perspective on a regular basis.
What Is Peering?
Peering on the internet is akin to building direct express lanes between neighborhoods. Instead of all data (residents) relying on crowded highways (public internet), networks (neighborhoods) establish peering connections—dedicated pathways connecting them directly. This allows data to travel faster and more efficiently, reducing congestion and delays. Peering is like having exclusive lanes, streamlining communication between networks and enhancing the overall performance of the internet “transportation” system.
We connect to various types of networks to help move your data. I’ll explain the different types below.
The Bit Exchange
Every day we move multiple petabytes of traffic between our internet connectivity points and our scalable data center fabric layer to be delivered to either our SSD caching layer (what we call a “shard stash”) or spinning hard drives for storage.
Our data centers are connected to the world in three different ways.
1. Direct Internet Access (DIA)
The most common way we reach everyone is via a DIA connection with a Tier 1 internet service provider. These connections give us access to long-haul, high-capacity fiber infrastructure that spans continents and oceans. Connecting to a Tier 1 ISP has the advantage of scale and reach, but this scale comes at a cost—we may not have the best path to our customers.
If we draw out the hierarchy of networks that we have to traverse to reach you, it would look like a series of geographic levels (Global, Regional, and Local). The Tier 1 ISPs would be positioned at the top, leasing bandwidth on their networks to smaller Tier 2 and Tier 3 networks, which are closer to our customer’s home and office networks.
Since our connections to the Tier 1 ISPs are based on leased bandwidth, we pay based on how much data we transfer. The bill grows the more we transfer. There are commitments and overage charges, and the relationship is more formal since a Tier 1 ISP is a for-profit company. Sometimes you just want unlimited bandwidth, and that’s where the role of the internet exchange (IX) helps us.
2. Internet Exchange (IX)
We always want to be as close to the client as possible and our next connectivity option allows us to join a community of peers that exchange traffic more locally. Peering with an IX means that network traffic doesn’t have to bubble up to a Tier 1 National ISP to eventually reach a regional network. If we are on an advantageous IX, we transfer data locally inside a data center or within the same data center campus, thus reducing latency and improving the overall experience.
Benefits of an IX, aka the “Unlimited Plan,” include:
- Paying a flat rate per month to get a fiber connection to the IX equipment versus paying based on how much data we transfer.
- No price negotiation based on bandwidth transfer rates.
- No overage charges.
- Connectivity to lower tiered networks that are closer to consumer and business networks.
- Participation helps build a more egalitarian internet.
In short, we pay a small fee to help the IX remain financially stable, and then we can exchange as much or as little traffic as we want.
Our network connectivity standard is to connect to multiple Tier 1 ISPs and a localized IX at every location to give us the best of both solutions. Every time we have to traverse a network, we’re adding latency and increasing the total amount of time for a file to upload or download. Internet routing prefers the shortest path, so if we have a shorter (faster) way to reach you, we will talk over the IX versus the Tier 1 network.
3. Private Network Interconnect (PNI)
The most direct and lowest latency way for us to exchange traffic is with a PNI. This option is used for direct fiber connections within the same data center or metro region to some of our specific partners like Fastly and Cloudflare. Our edge routing equipment—that is, the appliances that allow us to connect our internal network to external networks—is connected directly to our partner’s edge routing equipment. To go back to our neighborhood analogy, this would be if you and your friend put a gate in the fences that connect your backyards. With a PNI, the logical routing distance between us and our partners is the best it can be.
IX Participation
Personally, the internet exchange path is the most exciting for me as a network engineer. It harkens back to the days of the early internet (IX points began as Network Access Points and were a key component of Al Gore’s National Information Infrastructure (NII) plan way back in 1991), and the growth of an IX feels communal, as people are joining to help the greater whole. When we add our traffic to an IX as a new peer, it increases participation, further strengthening the advantage of contributing to the local IX and encouraging more organizations to join.
Backblaze Joins the Equinix Silicon Valley (SV1) Internet Exchange
Our San Jose data center is a major point of presence (PoP) (that is, a point where a network connects to the internet) for Backblaze, with the site connecting us in the Silicon Valley region to many major peering networks.
In November, we brought up connectivity to Equinix IX peering exchange in San Jose, bringing us closer to 278 peering networks at the time of publishing. Many of the networks that participate on this IX are very logically close to our customers. The participants are some of the well known ISPs that serve homes, offices, and business in the region, including Comcast, Google Fiber, Sprint, and Verizon.
Now, for the Stats
As soon as we turned up the connection, 26% inbound traffic that was being sent to our DIA connections shifted to the local Equinix IX, as shown in the pie chart below.
The below graph shows our peering traffic load over the edge router and how immediately the traffic pattern changed as soon as we brought up the peer. Green indicates inbound traffic, while yellow shows outbound traffic. It’s always exciting to see a project go live with such an immediate reaction!
To give you an idea of what we mean by better network proximity, let’s take a look at our improved connectivity to Google Fiber. Here’s a diagram of the three pathways that our edge routers see that show how to get to Google Fiber. With the new IX connection, we see a more advantageous path and pick that as our method to exchange traffic. We no longer have to send traffic to the Tier 1 providers and can use them as backup paths.
What Does This Mean for You?
We here at Backblaze are always trying to improve the performance and reliability of our storage platform while scaling up. We monitor our systems for inefficiencies, and improving the network components is one way that we can deliver a better experience.
By joining the Equinix SV1 peering exchange, we shorten the number of network hops that we have to transit to communicate with you. And that reduces latency, speeding up your backup job upload, allowing for faster image download, or supporting Partners.
Cheers from the NetEng team! We’re excited to start this series and bring you more content as our solutions evolve and grow. Some of the coverage we hope to share in the future includes analyzing our proximity to our peers and Partners, how we can improve those connections further, and stats to show the amount of bits per second that we process in our data centers to ensure that we not only have a file, but all the related redundancy shard components related to it. So, stay tuned!
