7.7.50 RAT Type
29.0603GPPGeneral Packet Radio Service (GPRS)GPRS Tunnelling Protocol (GTP) across the Gn and Gp interfaceRelease 17TS
The "RAT Type" information element is used to indicate which Radio Access Technology is currently serving the UE as perceived per the SGSN.
|
Bits |
||||||||||
|
Octets |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
||
|
1 |
Type = 151 (Decimal) |
|||||||||
|
2-3 |
Length = 1 |
|||||||||
|
4 |
RAT Type value |
|||||||||
Figure 7.7.50.1: RAT Type Information Element
Table 7.7.50.1: RAT Type values
|
RAT Type values |
Value(s) (Decimal) |
|
<reserved> |
0 |
|
UTRAN |
1 |
|
GERAN |
2 |
|
WLAN |
3 |
|
GAN |
4 |
|
HSPA Evolution |
5 |
|
E-UTRAN |
6 |
|
<spare> |
7-255 |
NOTE 1: Currently it is only possible to detect the difference between GERAN and UTRAN when GERAN Gb mode is used. If GERAN Iu mode is used, then an SGSN may not be able to detect the difference between GERAN and UTRAN. Across the Gb interface, the SGSN may also not be able to detect the difference between GERAN and GAN. If SGSN cannot detect that the HSPA Evolution 3GPP TR 25.999 [40] network is behind the Iu interface, the SGSN will send the "UTRAN" RAT Type.
NOTE 2: For the Iu interface case, if the SGSN detects UTRAN or HSPA, it sets the RAT-Type to "UTRAN". If the SGSN detects HSPA+, it sets the RAT-Type to "HSPA Evolution", otherwise the SGSN will send the "UTRAN" RAT Type.
NOTE 3: The RAT Type value E-UTRAN is applicable only for MME sending the "SGSN Context Request" message.