3GPP 23.501 v20.2.0 — the document's own text
5.7.3.7 Maximum Data Burst Volume
Taught in 14. What the network promises (The 5G system architecture, in depth), 5. The connection, and what is promised on it (The 5G system architecture, overview).
Each GBR QoS Flow with Delay-critical resource type shall be associated with a Maximum Data Burst Volume (MDBV).
MDBV denotes the largest amount of data that the 5G-AN is required to serve within a period of 5G-AN PDB.
Every standardized 5QI (of Delay-critical GBR resource type) is associated with a default value for the MDBV (specified in QoS characteristics Table 5.7.4.1). The MDBV may also be signalled together with a standardized 5QI to the (R)AN and if it is received, it shall be used instead of the default value.
The MDBV may also be signalled together with a pre-configured 5QI to the (R)AN and if it is received, it shall be used instead of the pre-configured value.