A traffic flow
template (TFT) is an information element that specifies parameters and
operations for a Packet Data Protocol (PDP) context. This information element
may be used to transfer extra parameters to the network (for example, the
Authorization Token; see 3GPP TS 24.229 ). The TFT may contain packet
filters for the downlink direction, uplink direction, or for both directions.
The packet filters
determine the traffic mapping to PDP contexts. Ideally, the network uses the
downlink packet filters while the mobile stations use the uplink packet
filters. This behavior is also seen for a packet filter that applies to both
The TFT is a type 4
information element with a minimum length of 3 octets. The maximum length for
the IE is 257 octets.
Currently, there is
a requirement for an Operator to identify and filter data traffic based on the
“Type of Service (TOS)/Traffic class” information. This information needs to be
configured as part of the Predefined or Dynamic rules (or both). Also, the
Operator wants to send “Type of Service (TOS)/Traffic Class" information as
part of TFT in the Create Bearer Request (CBR) and Update Bearer Request (UBR)
messages, which can be triggered via the Local Policy or PCRF.
For Dynamic rules,
the P-GW already supports "Type of Service (TOS)/Traffic class" information
that is used to identify specific data traffic. However, for Predefined rules,
there is no option available to configure "Type of Service(TOS)/Traffic class"
information as part of packet filter configuration.
introduces the ip
tos-traffic-class CLI to configure Type of Service (TOS)/Traffic
class information in the packet filter configured under charging action to
address the Operator requirements.