Network Infrastructure

- Overview

Data center is a pool of resources (computational, storage, network) interconnected using a communication network. A Data Center Network (DCN) holds a pivotal role in a data center, as it interconnects all of the data center resources together. DCNs need to be scalable and efficient to connect tens or even hundreds of thousands of servers to handle the growing demands of Cloud computing. Today’s data centers are constrained by the interconnection network.  

A conventional data center network (DCN) refers to a traditional, established design for connecting servers and other devices within a data center, typically using a hierarchical architecture with dedicated hardware like switches and routers to manage network traffic, as opposed to newer, more software-defined networking technologies; essentially, it's the standard, well-understood way of building a data center network with dedicated physical devices to control data flow. 

Key points about conventional data center networks:

• Hierarchical structure: Often features a three-tier architecture with a core layer for high-speed backbone connectivity, an aggregation layer for traffic management, and an access layer to connect individual servers and devices. 
• Dedicated hardware: Relies on dedicated physical devices like switches, routers, and firewalls to manage network traffic. 
• Manual configuration: Typically requires manual configuration and management of network devices. 

Contrast with modern approaches:

• Software-Defined Networking (SDN): A more flexible approach where network control is centralized in software, allowing for dynamic network management and configuration. 
• Network Function Virtualization (NFV): Enables virtualized network functions to run on standard servers, offering greater scalability and agility.

- Conventional Data Center Networks

A traditional data center network (DCN) consists of: servers that manage workloads and respond to client requests; switches that connect devices together; routers that perform packet forwarding functions; controllers that manage the workflow between network devices; gateways that are connection points between the data center network and the wider Internet; and clients that are consumers of packet information. 

Resource sharing on a network is based on a common mapping system of network standards or technologies. For modern networks, this shared map is typically based on the Internet Protocol (IP), Ethernet, and other related network technologies. 

Layer 3 IP addresses (IP routing) are designed to give intermediate forwarding agents in the network (called routers) clues about the general direction to move packets of data. Using the Transmission Control Protocol (TCP/IP), routers can pass packets to each other, which is essentially based on a best guess.

Another common data center technology is Ethernet, which uses media access control (MAC) addresses to connect devices.

To overcome the limitations of these basic network technologies, many additional network protocols have been developed, including VXLAN and OpenFlow, some of which can be performed as "overlays" on top of the basic network infrastructure.These components form the infrastructure of the data center network. 

As the infrastructure has evolved, the functions of these components no longer need to be implemented by separate physical devices. Virtualization enables some or all of these component roles to be implemented by software.

- Next Generation Data Center Network Infrastructure

A "next generation data center network infrastructure" refers to a modern data center network design that leverages advanced technologies like software-defined networking (SDN), high-speed connectivity, automation, and intelligent resource allocation to deliver increased scalability, flexibility, efficiency, and security compared to traditional data center networks, often incorporating features like modular design, distributed computing, and advanced security measures to handle the demands of modern data-intensive applications like AI and machine learning. 

Key characteristics of next generation data center network infrastructure: 

• Software-defined networking (SDN): Centralized management of network functions through software, allowing for dynamic configuration and resource allocation.
• High-speed connectivity: Utilizing high-bandwidth network links like 400GbE or even 800GbE to support large data transfers.
• Network virtualization: Creating multiple virtual networks on a single physical infrastructure for better isolation and resource utilization.
• Automated provisioning: Automatically configuring network components based on application needs, reducing manual intervention.
• Intelligent traffic management: Employing advanced algorithms to optimize network traffic flow, minimizing latency and maximizing throughput.
• Edge computing integration: Extending data processing closer to the data source for faster response times in distributed environments.
• Composable infrastructure: Modular components that can be easily combined and reconfigured to meet evolving needs.
• Enhanced security features: Advanced security protocols and threat detection mechanisms to protect against cyberattacks.

Benefits of next generation data center network infrastructure: 

• Scalability: Ability to quickly add or remove computing resources as needed to handle fluctuating workloads.
• Agility: Rapid deployment of new applications and services with flexible network configuration
• Cost efficiency: Optimized resource utilization and reduced power consumption through intelligent management
• Resiliency: High availability and fault tolerance through redundancy and automated failover mechanisms