such as Twitter, Facebook Messenger, and Snapchat. Others are designed for private or internal use, such as Slack, Discord, Line, Telegram, WeChat, Signal, WhatsApp, Google Chat, Cisco Spark, Zoom, Workplace by Facebook, Microsoft Teams, and Skype. Most of these messaging services are designed with security as a key feature, often employing multifactor authentication and transmission encryption.

Load Balancing

The purpose of load balancing is to obtain more optimal infrastructure utilization, minimize response time, maximize throughput, reduce overloading, and eliminate bottlenecks. A load balancer is used to spread or distribute network traffic load across several network links or network devices. Although load balancing can be used in a variety of situations, a common implementation is spreading a load across multiple members of a server farm or cluster. Scheduling or load balancing methods are the means by which a load balancer distributes the work, requests, or loads among the devices behind it. A load balancer might use a variety of scheduling techniques to perform load distribution, as described in Table 12.1.

TABLE 12 . 1   Common load-balancing scheduling techniques

Locality based (geoEach packet or connection is assigned a destination based on the destinagraphic) tion’s relative distance from the load balancer (used when cluster mem-

bers are geographically separated or across numerous router hops).