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.