13 GTP parameters

09.603GPPGeneral Packet Radio Service (GPRS)GPRS Tunnelling Protocol GPT) across the Gn and Gp InterfaceRelease 1998TS

The GTP system parameters defined here and their recommended values shall not be fixed, but shall be possible to configure as described in section ‘Reliable delivery of signalling messages’.

13.1 Timers

The timer T3-RESPONSE holds the maximum wait time for a response of a signalling request message.

The timer T3-TUNNEL holds the time when PDUs shall be forwarded from the old SGSN to the new SGSN. The timer is started in the old SGSN when it receives a GTP SGSN Context Request message and there is at least one active PDP context. GTP shall indicate to the upper layer when the timer has expired. The recommended timer value is 20 seconds.

13.2 Others

The counter N3-REQUESTS holds the maximum number of attempts made by GTP to send a signalling request message. The recommended value is 5.

The N3-BUFFER-SIZE is the size of the receive buffer for G-PDUs and signalling request messages. The recommended value is 8192.

Tables

Table 1: Signalling messages 12

Table 2: Information elements in an Echo Request 14

Table 3: Information elements in an Echo Response 14

Table 4: Information elements in a Create PDP Context Request 16

Table 5: Information elements in a Create PDP Context Response 18

Table 6: Information elements in an Update PDP Context Request 19

Table 7: Information elements in an Update PDP Context Response 20

Table 8: Information elements in a Delete PDP Context Request 20

Table 9: Information elements in a Delete PDP Context Response 21

Table 10: Information elements in a Create AA PDP Context Request 22

Table 11: Information elements in a Create AA PDP Context Response 23

Table 12: Information elements in a Delete AA PDP Context Request 24

Table 13: Information elements in a Delete AA PDP Context Response 24

Table 14: Information elements in an Error Indication 25

Table 15: Information elements in a PDU Notification Request 25

Table 16: Information elements in a PDU Notification Response 26

Table 17: Information elements in a PDU Notification Reject Request 26

Table 18: Information elements in a PDU Notification Reject Response 27

Table 19: Information elements in a Send Routeing Information for GPRS Request 28

Table 20: Information elements in a Send Routeing Information for GPRS Response 28

Table 21: Information elements in a Failure Report Request 29

Table 22: Information elements in a Failure Report Response 29

Table 23: Information elements in a Note MS Present Request 30

Table 24: Information elements in a Note MS Present Response 30

Table 25: Information elements in an Identification Request 31

Table 26: Information elements in an Identification Response 31

Table 27: Information elements in a SGSN Context Request 32

Table 28: Information elements in a SGSN Context Response 33

Table 29: Information elements in a SGSN Context Acknowledge 34

Table 30: Cause values 36

Table 31: Use of the Cause values 36

Table 32: Reordering Required values 39

Table 33: MS Validated values 40

Table 34: Selection mode values 41

Table 35: PDP Type Organization values 43

Table 36: ETSI defined PDP Type values 43

Table 37: Used Cipher values 46

Table 38: Reordering Required values 48

Table 39: VPLMN Address Allowed values 48

Figures

Figure 1: GPRS Logical Architecture with interface name denotations 9

Figure 2: Outline of GTP header 10

Figure 3: Tunnel ID (TID) format 11

Figure 4: Signalling Plane – Protocol stack 11

Figure 5: GTP header followed by subsequent Information Elements 13

Figure 6: GGSN – HLR Signalling via a GTP-MAP protocol-converter in a GSN 27

Figure 7: Type field for TV and TLV format 34

Figure 8: Cause information element 35

Figure 9: IMSI information element 37

Figure 10: RAI information element 37

Figure 11: TLLI information element 38

Figure 12: The Packet TMSI information element 38

Figure 13: Quality of Service (QoS) Profile information element 38

Figure 14: Reordering Required information element 39

Figure 15: Authentication Triplet information element 39

Figure 16: MAP Cause information element 39

Figure 17: P-TMSI Signature information element 40

Figure 18: MS Validated information element 40

Figure 19: Restart counter information element 40

Figure 20: Selection mode information element 41

Figure 21: Flow Label Data information element 41

Figure 22: Flow Label Signalling information element 41

Figure 23: Flow Label Data II information element 42

Figure 23A: MS Not Reachable Reason Information Element 42

Figure 24: Charging ID information element 42

Figure 25: End User Address information element 43

Figure 26: End User Address information element for IPv4 44

Figure 27: End User Address information element for IPv6 44

Figure 28: End User Address information element for X.25 44

Figure 29: End User Address information element for PPP 45

Figure 32: PDP Context information element 48

Figure 33: Access Point Name information element 49

Figure 34: Protocol Configuration Options information element 49

Figure 35: GSN Address information element 49

Figure 36: MSISDN information element 50

Figure 37: Charging Gateway Address information element 50

Figure 38: Private Extension information element 51

Figure 39: Transmission Plane – Protocol Stack 51

Annex A (informative):
Naming convention

A naming convention that will make it possible for DNS servers to translate logical names for GSNs and RAs to physical IP addresses is described in this informative annex. The use of logical names is optional, but if the option is used, it shall comply with the naming convention described in this annex.