Qos in Telecomunications means Quality-of-Service.

In the field of telecommunications and computer networks, the term Quality of Service (QoS) may tend to two interpretations related but distinct:

  1. In circuit-switched networks, refers to the probability of success in establishing a connection to a destination.
  2. In packet switched networks relates to the guaranteed bandwidth or, in many cases, is used to refer to informally probability of a packet cycle between two network points.