# A Split-Central-Buffered Load-Balancing Clos-Network Switch with In-Order Forwarding

## TL;DR

This paper introduces a load-balancing Clos-network switch with split central buffers that ensures high throughput, in-sequence forwarding, and low complexity without requiring memory speedup or central-stage expansion.

## Contribution

It proposes a novel configuration scheme for a load-balancing Clos-network switch with split central modules, achieving 100% throughput and in-sequence forwarding with low complexity.

## Key findings

- Achieves 100% throughput under various traffic conditions.
- Ensures in-sequence forwarding without memory speedup.
- Demonstrates high performance through simulation studies.

## Abstract

We propose a configuration scheme for a load-balancing Clos-network packet switch that has split central modules and buffers in between the split modules. Our split-central-buffered Load-Balancing Clos-network (LBC) switch is cell based. The switch has four stages, namely input, central-input, central-output, and output stages. The proposed configuration scheme uses a pre-determined and periodic interconnection pattern in the input and split central modules to load-balance and route traffic. The LBC switch has low configuration complexity. The operation of the switch includes a mechanism applied at input and split-central modules to forward cells in sequence. The switch achieves 100\% throughput under uniform and nonuniform admissible traffic with independent and identical distributions (i.i.d.). These high switching performance and low complexity are achieved while performing in-sequence forwarding and without resorting to memory speedup or central-stage expansion. Our discussion includes throughput analysis, where we describe the operations that the configuration mechanism performs on the traffic traversing the switch, and proof of in-sequence forwarding. A simulation study is presented as a practical demonstration of the switch performance on uniform and nonuniform i.i.d. traffic.