As the cause of lag, latency is public enemy #1 in eCommerce. Nothing is better at killing an online experience and driving users away from a site, possibly never to return. Most of us probably assume it’s an issue with bandwidth, but often the problem can be traced back to high latency.
Read on to learn more about what causes latency and how web hosts like Nexcess use Internet Exchanges to reduce it.
Host with a provider that is part of the Detroit Internet Exchange. Learn more.
What Is Latency?
Latency refers to how long data takes to travel between the device requesting the data and the device providing it. Usually, the distance between these two points requires the use of other devices along the way. Each additional device, or hop, has the potential to increase latency. Indirect routes have more hops and are therefore undesirable.
How Does an Internet Exchange Work?
Local Network Service Providers (NSP, but also known as Internet Service Providers or ISP) typically have an inefficient infrastructure and do not reliably provide the most direct route. For example, a user in Detroit, MI attempts to contact a network in Ann Arbor, MI, but the NSP routes the traffic through Chicago, IL. This indirect path pushes traffic through multiple routers and hundreds more miles of fiber optic cable. Typically, each additional mile increases latency by about 9 microseconds due to the light in those cables having to travel farther.
Reputable web hosting companies are well aware of this problem, and even though they may be in competition with one another, their solution is cooperation. This cooperation is known in the industry as an Internet Exchange (IX) and provides a more direct path by eliminating the need for ISPs to carry local traffic.
By allowing companies to directly peer with one another and exchange traffic in a more direct path, there are less hops. This, in turn, generally means lower network latency.
At Nexcess, we minimize latency for our clients by participating in the Detroit Internet Exchange (DET-IX).
Cage Match: DET-IX Versus NSP
IX participants are connected in a shared network with other members, allowing them to communicate locally and bypass the NSP. Using a tool like My traceroute (MTR), we can compare latency between DET-IX and NSP.
Here, we try reaching https://cloudflare.com through one of our NSPs.
The IP addresses show traffic leaving our network in Southfield, MI and then traveling through Cleveland, OH before finally reaching https://cloudflare.com in Toronto. While a better route, this is still similar to the pathway described above, where a user Detroit, MI attempts to contact a network in Ann Arbor, MI.
In the industry, the effect of indirect paths backtracking over their own route is often known as “tromboning” and it is universally viewed as unfavorable for latency.
These extra hops through the network add latency as the traffic passes through each router. As shown in the last entry in the Last column, the average response time of 10.4ms. This is good, but it can be improved.
Improving Internet Exchange Point Architecture
Here’s the same test, but using DET-IX to reach https://cloudflare.com.
Traffic again leaves our network in Southfield, but through DET-IX where Cloudflare is also participating. The path uses three less hops, avoids tromboning, and improves the average response time for 100 packets to 0.5 ms, nearly a 10ms reduction.
In eCommerce, faster is almost always better. Shoppers have nearly no patience for lag, the modern-day equivalent of long lines. Fast stores sell more than slow stores, and better page-load times elevate your ranking on Google search engine results pages (SERPs), driving more traffic to your site.
Good and Getting Better!
This shared network relies on Border Gateway Protocol (BGP) to exchange routing and reachability information, and we use technology that both allow their use and accommodates future expansion. As DET-IX participation continues to grow, so does our ability to accept routes from new members.
Andrew has been working at Nexcess for six years. He started out with the Data Center Operations department before making the leap to Network Operations. Andrew has eight Juniper Networks certifications, with the highest level achieved being JNCIP-DC.
Posted in: Web Hosting Basics