QoS DSCP Marking – Zoom Help Center
IP accounting shows the entire ToS byte, while Netflow shows the ToS byte in hexadecimal format. The ToS byte value for EF is as follows: 128 64 32 16 8 4 2 1 1 0 1 1 1 0 0 0 A DSCP value of 46 ToS Header of IP Packet Used for DSCP Marking. The above diagram depicts an IP packet, with a close-up on the ToS portion of the header. The ToS bits were originally used for Precedence and ToS (delay, throughput, reliability, and cost) settings, but were later repurposed by RFC2474 for the more versatile DSCP settings. The four TOS bits were deprecated, and three of them were assigned to DiffServ QoS, in addition to the three precedence bits. DiffServ ended up with six bits, providing more than enough levels of QoS. After you define the application, you can mark it with a DSCP or IP TOS value in a QoS profile. The application can either inherit the DSCP or IP TOS value from a QoS class or you can create a QoS rule to mark it with a DSCP or IP TOS value. For more information about how to define an application, see Defining an Application.
IP accounting shows the entire ToS byte, while Netflow shows the ToS byte in hexadecimal format. The ToS byte value for EF is as follows: 128 64 32 16 8 4 2 1 1 0 1 1 1 0 0 0 A DSCP value of 46
If QoS is to make a difference, it requires a good deal more than just setting the DSCP, ToS or CoS values on the IP telephony device or PBX. If QoS is an important requirement in your VoIP projects, I strongly recommend that you read my follow-up article about QoS in practice. The most important part to understand with QoS is that it only helps when there is congestion and if there is constant congestion all you can do is to manage the fairness of the congestion. You will not have more bandwidth. Classification, marking and understanding the concept of a queue is the easy part.
Quality of service (QoS) is the description or measurement of the overall performance of a service, especially in terms of the user’s experience. Typically it is used in reference to telephony or computer networks, or to online and cloud-hosted services.
Jul 03, 2017 Network QoS Policies - Nokia