8.22 Fully Qualified TEID (F-TEID)
29.2743GPP3GPP Evolved Packet System (EPS)Evolved General Packet Radio Service (GPRS) Tunnelling Protocol for Control plane (GTPv2-C)Release 18Stage 3TS
Fully Qualified Tunnel Endpoint Identifier (F-TEID) is coded as depicted in Figure 8.22-1.
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Bits |
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Octets |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
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1 |
Type = 87 (decimal) |
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2to 3 |
Length = n |
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4 |
Spare |
Instance |
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5 |
V4 |
V6 |
Interface Type |
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6 to 9 |
TEID / GRE Key |
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m to (m+3) |
IPv4 address |
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p to (p+15) |
IPv6 address |
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k to (n+4) |
These octet(s) is/are present only if explicitly specified |
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Figure 8.22-1: Fully Qualified Tunnel Endpoint Identifier (F-TEID)
The following flags are coded within Octet 5:
– Bit 8 – V4: If this bit is set to "1", then IPv4 address field exists in the F-TEID, otherwise the IPv4 address field is not present at all.
– Bit 7 – V6: If this bit is set to "1", then IPv6 address field exists in the F-TEID, otherwise the IPv6 address field is not present at all.
At least one of V4 and V6 shall be set to "1", and both may be set to "1".
– Bit 6 to Bit 1 – Interface Type: This 6 bit wide integer can take the following values representing interface type and endpoint:
0: S1-U eNodeB GTP-U interface
1: S1-U SGW GTP-U interface
2: S12 RNC GTP-U interface
3: S12 SGW GTP-U interface
4: S5/S8 SGW GTP-U interface
5: S5/S8 PGW GTP-U interface
6: S5/S8 SGW GTP-C interface
7: S5/S8 PGW GTP-C interface
8: S5/S8 SGW PMIPv6 interface (the 32 bit GRE key is encoded in 32 bit TEID field)
9: S5/S8 PGW PMIPv6 interface (the 32 bit GRE key is encoded in the 32 bit TEID field, see clause 6.3 in 3GPP TS 29.275 [26])
10: S11 MME GTP-C interface
11: S11/S4 SGW GTP-C interface
12: S10/N26 MME GTP-C interface
13: S3 MME GTP-C interface
14: S3 SGSN GTP-C interface
15: S4 SGSN GTP-U interface
16: S4 SGW GTP-U interface
17: S4 SGSN GTP-C interface
18: S16 SGSN GTP-C interface
19: eNodeB/gNodeB GTP-U interface for DL data forwarding
20: eNodeB GTP-U interface for UL data forwarding
21: RNC GTP-U interface for data forwarding
22: SGSN GTP-U interface for data forwarding
23: SGW/UPF GTP-U interface for DL data forwarding
24: Sm MBMS GW GTP-C interface
25: Sn MBMS GW GTP-C interface
26: Sm MME GTP-C interface
27: Sn SGSN GTP-C interface
28: SGW GTP-U interface for UL data forwarding
29: Sn SGSN GTP-U interface
30: S2b ePDG GTP-C interface
31: S2b-U ePDG GTP-U interface
32: S2b PGW GTP-C interface
33: S2b-U PGW GTP-U interface
34: S2a TWAN GTP-U interface
35: S2a TWAN GTP-C interface
36: S2a PGW GTP-C interface
37: S2a PGW GTP-U interface
38: S11 MME GTP-U interface
39: S11 SGW GTP-U interface
40: N26 AMF GTP-C interface
41: N19mb UPF GTP-U interface
Other values of "Interface Type" are spare and reserved for future use.
"Interface type" values with bit "6" set to 1 shall only be used between Rel-10 onwards GTPv2-C nodes.
NOTE 1: "Interface type" IE is defined with 5 bits only in the earlier releases of this specification, thus pre-Rel-10 GTPv2-C nodes can ignore bit "6" which is marked as "Spare" in earlier releases, allowing backward compatibility.
NOTE 2: Interface Type 8 is not used in this Release and in earlier Releases.
Octet 6 to 9 (TEID/GRE field) represent either a TEID or a GRE key. If both IPv4 and IPv6 addresses are present in F-TEID IE, then the TEID value shall be shared by both addresses.
Octets "m to (m+3)" and/or "p to (p+15)" (IPv4 address / IPv6 address fields), if present, contain respective address values.