Designing a network for low latency requires strategic focus on several core aspects, including server placement, peering arrangements, and protocol choices.
Placement is critical because the physical distance between endpoints affects round-trip time. Utilizing edge computing by placing servers closer to the end user minimizes this distance and reduces latency. Content delivery networks (CDNs) take advantage of this by deploying distributed points of presence (PoPs), which cache content near end-users to accelerate data retrieval. Servers are often located at key internet exchange points (IXPs) to leverage shared infrastructures and optimize routing efficiency.
Network peering involves establishing mutual arrangements between different networks to facilitate the direct exchange of traffic. This can significantly reduce latency by avoiding unnecessary hops through transit networks. Peering can be either public, using IXPs, or private, through dedicated connections. Effective peering strategies should focus on interconnecting with major networks carrying substantial user traffic and assessing peering policies to ensure optimal data flow.
Protocols play a significant role in latency. Choosing protocols optimized for speed and efficiency can drastically impact performance. For example, TCP's handshake mechanisms introduce overhead, but using protocols like QUIC can mitigate some latency through features like stream multiplexing, reduced handshake requirements, and improved congestion control. Similarly, HTTP/2 and HTTP/3 minimize latency through server push technologies and header compression.
Further protocol optimizations can be achieved by lowering MTU size to reduce packet fragmentation and leveraging application layer protocols and technologies that minimize data transfer sizes, such as gRPC and Protobuf.
Overall, achieving low latency in network design involves a comprehensive approach where placement, peering, and protocol choices are optimally aligned to deliver the best possible performance.