Voice and video traffic is particularly sensitive to measurements that the QoS feature shapes and controls, especially latency and jitter. For voice and video transmissions to be audible and clear, voice and video packets cannot be dropped, delayed, or delivered inconsistently. A best practice for voice and video applications, in addition to guaranteeing bandwidth, is to guarantee priority to voice and video traffic.
In this example, employees at a company branch office are experiencing difficulties and unreliability in using video conferencing and Voice over IP (VoIP) technologies to conduct business communications with other branch offices, with partners, and with customers. An IT admin intends to implement QoS in order to address these issues and ensure effective and reliable business communication for the branch employees. Because the admin wants to guarantee QoS to both incoming and outgoing network traffic, he will enable QoS on both the firewall’s internal- and external-facing interfaces.