Session handling

A PFCP session is set up to control the creation, modification, and deletion of a bundle of PDRs. There is a single PFCP session per connected device.

Overview

PFCP sessions adhere to the following generic scope rules as defined in TS 29.244.
  • Identifiers (for example, FAR ID, QER ID, URR ID) are only unique within a session unless explicitly stated otherwise.
  • PDRs belonging to different sessions must not have the same PDI matching criteria.
PFCP messages are used to add, update, or delete rules as follows.
  • PFCP Session Establishment adds rules.
  • PFCP Session Modification can add, modify, and delete specific rules.
  • PFCP Session Deletion deletes all rules.

PFCP Session Modification and PFCP Session Report are used to send statistics or other information from the BNG-UP to the MAG-c.

PFCP session example

The following tables describe an example for a dual-stack PPPoE session, with session ID 100, IP anti-spoofing enabled, and single-session per MAC.

The following table describes the reused and top-level IEs, such as Traffic Endpoint IEs, QER IE, URR IE, and LCP PPP Connectivity IE. PDR and FARs for an example PPPoE session lists the PDRs with their accompanying PDR and related FAR. FARs are directly in the table for convenience.

Table 1. Top level IEs for an example PPPoE session
IE Contents
PDN Type 
Ethernet
Traffic Endpoint 1 
BBF) Logical Port = 1/2/3,
S-TAG = 4,
C-TAG = 5,
MAC address = SOUR-00:00:5E:00:53:01
Traffic Endpoint 2 
(BBF) Logical Port = 1/2/3,
S-TAG = 4,
C-TAG = 5,
MAC address = SOUR-00:00:5E:00:53:01,
(BBF) PPPoE Session ID = 100,
UE IP Address = 192.0.2.2, 2001:db8:1::/56 (IPv6D=8), 2001:db8:2:1::/64
Traffic Endpoint 3 
UE IP Address = 192.0.2.2, 2001:db8:1::/56 (IPv6D=8), 2001:db8:2:1::/64,
Network-Instance = 'network'
Traffic Endpoint 4 
Local F-TEID = v46, F-TEID CHOOSE
QER 1 
QER Correlation ID = 1
URR 1 
Measurement Method = VOLUM
Reporting Triggers = PERIO
Measurement Period = 600 //10m
(BBF) PPP LCP Connectivity 
Traffic Endpoint ID = 1
(BBF) PPP LCP Magic Number = 0x12345678
(BBF) Verification Timers = interval 3000, count 3
Nokia UP Aggregate Route 
Network-Instance = 'network'
Framed-Route = 192.0.2.1/24
Framed-IPv6-Route = 2001:db8:1::/48
Framed-IPv6-Route = 2001:db8:2::/56
Table 2. PDR and FARs for an example PPPoE session
PDR PDI FAR
PDR 1 (UP to CP) 
Source Interface = Access
Traffic-Endpoint = 1
Ethernet Packet Filter: //PADI, PADR
Ethertype = 0x8863,
Ethernet Packet Filter: //PPP ctl
Ethertype = 0x8864,
(BBF) PPP Protocol = control
Ethernet Packet Filter: //DHCPv6
Ethertype = 0x8864,
(BBF) PPP Protocol = data
SDF: Permit out 17 from any to any 547,
Ethernet Packet Filter: //RS
Ethertype = 0x8864,
(BBF) PPP Protocol = data
SDF: Permit out 58 from any to FF02::2
 
FAR 1
Apply Action = forward
Forwarding Parameters:
Destination Interface = CP-Function
Outer Header Creation = GTP-U/UDP/IPv4, TEID 2000, IPv4 203.0.113.1, IPv6 2001:db8:1234::1
PDR 2 (CP to UP)
Outer Header Removal = GTP/UDP/IPv4
 
Source Interface = CP Function
Traffic-Endpoint = 4
 
FAR 2
Apply Action = forward
Forwarding Parameters:
- Destination Interface = Access
- Linked Traffic Endpoint ID = 1
PDR 3 (upstream data)
BBF Outer Header Removal = PPP/PPPoE/Ethernet
QER ID = 1
URR ID = 1
Activate Predefined Rules = 'IPoE-HQoS'
 
Source-interface = access
Traffic Endpoint = 2
 
FAR 3
Apply Action = forward
Forwarding Parameters:
- Destination-Interface = SGi-LAN
- Network-Instance = 'network'
PDR 4 (downstream data)
QER ID = 1
URR ID = 1
Activate Predefined Rules = 'IPoE-HQoS'
 
Source-interface = SGi-LAN
Traffic-Endpoint = 3
 
FAR 4
Action = forward
Forwarding Parameters:
- Destination Interface = access
- BBF Outer Header Creation = Traffic-Endpoint
- BBF Outer Header Creation = Traffic-Endpoint
- Linked Traffic Endpoint ID = 2
- (BBF) MTU = 1400