What is SPDY?

Communications protocols are what make the internet tick. Consisting of digital rules that govern the way that messages and data are exchanged between computers, they are integral for the smooth running of any computer or network, both global and local. Over the years, many protocols have been developed, each offer specific advantages over those that came before it. A new protocol, known as SPDY has recently started gaining popularity, but what is SPDY and how can it benefit you?

SPDY (derived from the word ‘speedy’) is one of the newest communications protocols and its development is being spearheaded by Google. With the aim being to provide a standardised build of the protocol, the team behind its development are committed to creating a protocol that reduces page load times compared to the similar protocol HTTP. Whilst providing better performance than HTTP, the goal is not for SPDY to replace HTTP, but rather modify the way in which it is used.

How One AI-Driven Media Platform Cut EBS Costs for AWS ASGs by 48%

How One AI-Driven Media Platform Cut EBS Costs for AWS ASGs by 48%

SPDY must be supported by both web browsers and web servers in order to work, and it is currently supported by Chrome, Firefox, Opera and Internet Explorer. There are several performance-based benefits to using browser that support the SPDY protocol:

  1. SPDY is two layered, meaning that the upper layer handles HTTP requests whilst the lower layer deals with encoding and sending data. This is great, as it allows concurrent HTTP requests to be executed per TCP/IP session, resulting in improved performance.
  2. By operating in this way, SPDY also reduces the number of TCP ‘handshakes’, further speeding up response times. Furthermore, this reduction in the number of requests means there are fewer chances for packet loss, which can require requests and data to be resent.
  3. HTTP headers consist of a lot of redundancy, and therefore wasted bandwidth. SPDY compresses HTTP headers, further reducing the number of bytes that need to be transmitted across networks.
  4. Server push functionality allows associated resources from a requested URL to be delivered in the background before they have been clicked on. For example, it may download additional pages from a website when you have only clicked on the home page. Doing this silently in the background, it allows these extra resources to load more quickly if they are eventually clicked on.
  5. Server hints, which work similarly to server push, sends the URL of additional page content as opposed to the actual resources, making future requests on the same website slightly faster.
Bar chart comparing average page load times (PLT) for SPDY and HTTP under varying packet loss rates.
Packet loss comparison between HTTP and SPDY. SPDY clearly comes on top, with a much lower level of packet loss.

These points all mean that SPDY can deliver some strong performance increases when it comes to delivering data online. Google’s whitepaper on SPDY claims that these performance improvements could range from 27% – 60% compared to page load times across TCP without SSL and 39% – 55% compared to TCP with SSL. These are some serious speed improvements.

In addition to these performance gains, SPDY also contains some significant security enhancements. This is because all current iterations of SPDY have SSL (secure sockets layer) built in and mandated, providing encrypted traffic at all times. This is great in a world where secure browsing is increasingly become a concern for most users.

Ad banner promoting GlobalDots for website speed and reliability.

SPDY is an exciting new development in the web industry and its push to becoming standardised is certainly a great thing. As more browsers and web servers make use of the protocol, we will see ever increasing performance benefits across a number of different websites and applications. And when used in conjunction with advanced web acceleration technologies such as content delivery networks, we will begin to experience how the web of tomorrow might look and feel.

Latest Articles

Weak Defences: The Most Hackable Sports Passwords

We get it. Thinking of another password that you haven’t used before can be frustrating – especially when we have to change or update our passwords so regularly. But while it might be tempting to use your favourite sports teams and clubs as passwords, it’s a risky move for your cyber security.  Using unique passwords […]

7th April, 2025
Solving Network Security Issues for Rapidly Growing Global Businesses

Introduction Ryohin Keikaku is a global manufacturing and retail company that handles everything from product planning to sales for products known as “Mujirushi-Ryohin” in Japan and “MUJI” overseas. To keep pace with its rapid expansion—adding 100 new stores annually in Japan—and its growing global presence, now spanning 225 locations across 20 countries, including 50 stores […]

3rd April, 2025
Closing the Gaps in API Security: How to Build Visibility and Protection for Modern Enterprises

APIs may be your organization’s greatest enabler, but without proper context, they can become its Achilles’ heel. APIs power modern digital ecosystems, connecting applications, enabling seamless machine-to-machine communication, and driving operational efficiencies. However, as APIs become the backbone of enterprises, they also represent an expanding attack surface — one that traditional Web Application and API […]

27th February, 2025

Unlock Your Cloud Potential

Schedule a call with our experts. Discover new technology and get recommendations to improve your performance.

    GlobalDots' industry expertise proactively addressed structural inefficiencies that would have otherwise hindered our success. Their laser focus is why I would recommend them as a partner to other companies

    Marco Kaiser
    Marco Kaiser

    CTO

    Legal Services

    GlobalDots has helped us to scale up our innovative capabilities, and in significantly improving our service provided to our clients

    Antonio Ostuni
    Antonio Ostuni

    CIO

    IT Services

    It's common for 3rd parties to work with a limited number of vendors - GlobalDots and its multi-vendor approach is different. Thanks to GlobalDots vendors umbrella, the hybrid-cloud migration was exceedingly smooth

    Motti Shpirer
    Motti Shpirer

    VP of Infrastructure & Technology

    Advertising Services