This chapter
describes the CDR fields supported by the system for use in SGSN.
CDR Fields
Access Point Name
Network Identifier
The network
identifier (NI) portion of the access point name (APN). The APN
typically corresponds to a registered Internet domain name and represents
the external packet data network (PDN). It is sent to the SGSN by
the MS (or determined locally by the HLR or configuration) and is
relayed to the GGSN in the Create PDP Context Request message.
Format
The APN string may
consist of 1 to 63 characters composed of alphanumerics (upper-
and/or lowercase letters and digits 0-9), periods and dashes
IA5 String
Access Point Name
Operator Identifier
The operator
identifier (OI) part of the APN. The OI is composed of three parts
(<operator’s MNC>.<operator’s MCC>.gprs)
and the first two combined uniquely identify the network operator’s PLMN.
APN Selection Mode
An index indicating
how the APN was selected.
The following APN
selection mode indexes are possible:
- 0: MS or network provided
APN, subscribed verified
- 1: MS provided APN,
subscription not verified
- 2: Network provided
APN, subscription not verified
Format
Unsigned Integer
Enumerated for custom33
Enumerated integer for
custom41
CAMEL Information
Set of CAMEL
information related to PDP context. This field is present if CAMEL
Charging Information is received by the HLR in ISD message.
Cause for Record
Closing
The reason the
record is closed and released from the SGSN.
Some of the possible
reasons are:
- normalRelease (0):
The PDP context was terminated normally through a PDP context release
(end of context or SGSN change) or a GPRS detach.
- abnormalRelease (4):
The PDP context was abnormally terminated.
- volumeLimit (16): The
CDR is released due to exceeding volume limit.
- timeLimit (17): The
CDR is released due to exceeding time limit.
- sGSNChange (18):
- maxChangeCond (19):
The CDR is released due to exceeding the changed condition limit.
- managementIntervention
(20): The record was closed due to an O&M request.
- intraSGSNIntersystemChange
(21): The CDR is released when MS moves from 3G<->2G and vice
versa within the same SGSN.
-
RAT Change (22): The
CDR is released when the MS moves from one radio access technology
RAT) to another.
-
plmn change (101):
The CDR is released when the MS moves from one PLMN to another PLMN.
- Partial Record Generation:
A partial CDR was generated for reasons such as the reaching of
data volume or time (duration) limits, or reaching the maximum number
of charging condition changes, or intraSGSNIntersystemChange change.
Cell Identifier
For GSM, the
Cell Identifier is defined as the Cell Id, reference 24.008. For
UMTS, it is defined as the Service Area Code in TS 25.413. This
field contains the CI (GSM) or the SAC (WCDMA) where the MS is located
when the S-CDR is opened. The first partial or single S-CDR reports
the value at PDP context activation. For any subsequent partial
S-CDRs, the accuracy of the reported value is limited to the value
at the last RA update reported by the MSCell identity for GSM or
Service Area Code (SAC) for UMTS at “Record Opening Time”.
Change Condition
The Change Condition
field is part of the ChangeOfCharCondition element in the List of Traffic
Data Volumes.
Change Condition defines
the reason for closing the container; supported values include:
- qoSChanage
- tariffTime
- recordClosure
Change of Charging
Characteristics
Lists the charging
characteristics applied to the PDP context.
The SGSN can accept
charging characteristics from the HLR or use its own. SGSN-configured
charging characteristics are specified as part of the operator policy
and are applied to subscriber PDP contexts through SGSN-Operator-Policy templates.
Format
Hex Value Octet String
Change of Charging
Condition
Each traffic
volume container contains details related to a charging condition
as described in the following subsections. A new container is usually
created for a QoS change and for tariff changes.
Change Time
The Change Time
field is part of the ChangeOfCharCondition element in the List of
Traffic Volumes. Change Time identifies the local time when a change
condition occurred and the container was closed. The contents of
this field are a compact form of the UTC Time format containing
local time plus an offset to universal time. Binary coded decimal
encoding is employed for the digits to reduce the storage and transmission
overhead, for example: e.g. YYMMDDhhmmssShhmm.
Format
BCD encoded octet string
Charging Characteristics
Lists the charging
characteristics (CC) applied to the PDP context by the SGSN. The
SGSN can accept charging characteristics from the HLR, default values,
or use its own configured values.
Charging Characteristics
Selection Mode
The charging
characteristic (CC) type that the SGSN applied to the CDR. The following
values for this field are supplied:
- homeDefault: SGSN configured
charging characteristics for home subscribers are used. Home subscribers
are those that belong to the same PLMN as the one on which the GGSN
is located.
- visitingDefault: SGSN
configured charging characteristics for visiting subscribers are used.
Visiting subscribers are those that belong to a different PLMN than
the one on which the GGSN is located.
- roamingDefault: SGSN
configured charging characteristics for roaming subscribers are used.
Roaming subscribers are those that are serviced by an SGSN belonging
to a different PLMN than the one on which the GGSN is located.
- subscriptionSpecific:
This CC will be applied to S-CDR only if aPNSpecific CC is absent.
- aPNSpecific: For S-CDR
priority will be given to aPNSpecific Charging Characteristics Selection
mode. The aPNSpecific mode is from HLR (ISD Message).
Format
Enumerated Integer
Charging ID
Field specifies
the charging identifier, which can be used together with the GGSN
address to identify all records involved in a single PDP context.
The charging ID is generated by the GGSN at PDP context activation
and is transferred to the SGSN requesting the context. At an inter-SGSN
routing area update (ISRAU) the charging ID is transferred to the
new SGSN as part of each active PDP context. Each GGSN allocates
the charging ID independently and may allocate the same number prefix,
so the charging ID must always be combined with the GGSN address
to form a unique identifier for the PDP context.
Format
Integer (0..4294967295)
Length
1–4 Bytes / 1-5
Bytes (custom33 only)
Data Volume GPRS
Downlink
The Data Volume
GPRS Downlink field is a part of the ChangeOfCharCondition element
in the List of Traffic Volumes. It includes the number of octets
transmitted in the downlink direction during the timeframe specified
by the container. For each new container, the counter is reset and
does not accumulate. The data volume tabulated by the SGSN covers
the amount of user data transferred in the SNDCP PDUs (GSM) and
GTP-U T-PDUs (WCDMA). Data volumes retransmitted by RLC or LLC,
due to poor radio link conditions, are not tabulated. The data counted
includes the IP PDP bearer protocols, i.e. IP or PPP.
Data Volume GPRS
Uplink
The Data Volume
GPRS Uplink field is a part of the ChangeOfCharCondition element
in the List of Traffic Volumes. It includes the number of octets
received in the uplink direction during the timeframe specified
by the container. For each new container, the counter is reset and
does not accumulate. The data volume tabulated by the SGSN covers
the amount of user data transferred in the SNDCP PDUs (GSM) and
GTP-U T-PDUs (WCDMA). Data volumes retransmitted by RLC or LLC,
due to poor radio link conditions, are not tabulated. The data counted
includes the IP PDP bearer protocols, i.e. IP or PPP.
Default Transaction/SMS
Handling
This field indicates
whether or not a CAMEL encountered default GPRS- or SMS-handling. This
field is present only if default call handling has been applied.
Parameter is defined in HLR as part of CAMEL subscription information.
Format
Enumeration (Integer)
Diagnostics
This field is
included in the CDR when the PDP context is released. This field
is supported in G-CDRs but not for eG-CDRs.
It will contain one
of the following values:
- 36: If the SGSN sends
Delete PDP Context request
- 38: If the SGSN sends
Delete PDP Context request due to GTP-C/U echo timeout
with SGSN
- 26: If the SGSN sends
Delete PDP Context request for any other reason
Duration
This field contains
the duration for the record in seconds. For partial records, only
the interval described by the recordOpeningTime and the last ChangeTime
in the ListOfTrafficVolumes is counted. The Duration value is reset
for each new partial CDR. This value is converted from the internal
representation in milliseconds to an integer value representing
only seconds. The mechanism for this conversion (ceiling, floor,
round-off) can be configured.
Dynamic Address
Flag
The presence
of this field indicates that the PDP Address was dynamically allocated
for that particular PDP context during context activation. This
field is missing if the address is static (part of the PDP context
subscription).
GGSN Address
This field provides
the IP address for the control plane of the current serving GGSN,
which is equivalent to the configured ggsn-service address on the
GGSN. The standard 3GPP 32.298 offers a choice for the encoding
of the address to be either in binary or text format. The SGSN encodes
the address in binary format and includes the Octet String.
Format
Hex Value Octet String
IP Address
The IP address
format is used by multiple fields in the CDR, such as the GGSN address
or the Served PDP address. This entry is included here to avoid
duplication. For the IP address, both the binary and text format
and both IPv4 and IPv6 are specified in 3GPP 32.298.
For custom33 only,
served PDP IP address will be in IPV4 or IPV6. The SGSN and GGSN
transport interfaces should be IPV4 encoded.
- iPBinV4Address -- [0] --
OCTET STRING -- (SIZE(4)),
- iPBinV6Address -- [1] --
OCTET STRING -- (SIZE(16))
- iPTextV4Address -- [2] --
IA5String -- (SIZE(7..15)),
- iPTextV6Address -- [3] --
IA5String -- (SIZE(15..45))
Format
Hex Value Octet String
IPv4 Binary Address
This field contains
an IPv4 address in hexadecimal format. Depending on where the field
is used in the sequence of the CDR, it may contain either an SGSN
or GGSN address or the PDP IP address of the mobile subscriber.
Note: Note the difference between how the GSN address and the PDP
address are encoded. Currently, only IPV4 support is provided.
Format
Hex Value Octet String
Length
Varies for GSN address
or PDP address
IPv6 Binary Address
This field contains
an IPv6 address in hexadecimal format. Depending on where the field
is used in the sequence of the CDR, it may contain either an SGSN
or GGSN address or the PDP IP address of the mobile subscriber.
Note: Note the difference between how the GSN address and the PDP
address are encoded. Currently, only IPV4 support is provided.
Format
Hex Value Octet String
Length
Varies for GSN address
or PDP address
Level of CAMEL services
This field describes
the complexity of CAMEL invocation. Categories are the same as in
circuit switched services and measure of resource usage in VPLMN
requested by HPLMN.
- Basic: The CAMEL feature
is invoked only during the PDP context activation phase. (For example,
to modify APN_NI/APN_OI).
- Call duration supervision:
The PDP context duration or volume supervision is applied in the
gprsSSF of the VPLMN (Apply Charging message is received from the gsmSCF).
List of Traffic
Data Volumes
A list of the
changes that occurred in the charging conditions for this PDP context.
The list will include
one or more containers each including the following fields:
- QoS negotiated: Quality
of service (QoS) has been negotiated. The initial and final corresponding
data values are listed. This is only added for the first container
and the container after a QoS change.
- Uplink volume: The
number of octets (uncompressed) received from the MS. The initial
and final corresponding data values are listed.
- Downlink volume: The
number of octets (uncompressed) transmitted to the MS.The initial
and final corresponding data values are listed.
- Change Condition: Identifies
the reason that the container was closed such as tariff time change,
QoS change, or closing of the CDR.
- Change Time: A timestamp
identifying the time at which the volume container or the CDR closed.
For GPRS, data volumes
are in octets above the GTP layer and are separated for uplink and downlink
traffic. In UMTS, data volumes are in octets above the GTP-U layer
and are separated for uplink and downlink traffic.
Format
- QoS negotiated: Octet
String
- Uplink volume: Integer
- Downlink volume: Integer
- Change Condition: Integer
- Change Time: BCD Encoded
Octet String
Length
- QoS negotiated: 12
Bytes
- Uplink volume: 4 Bytes
- Downlink volume: 4
Bytes
- Change Condition: 1
Byte
- Change Time: 9 Bytes
List of Traffic
Volumes
This list includes
one or more Traffic Volume containers related to a “Change
of Charging Condition” as described in 6.7. The maximum
number of containers is configurable, see chapter 2.
This list includes
containers that include the following fields:
- QoS requested (optional)
- QoS negotiated (optional)
- data volume uplink
- data volume downlink
- change condition
- change time
Local Record Sequence
Number
This field contains
a unique sequence number associated with the NodeId field and independent
of the PDP context. Unless the LRSN rewrite feature is used on the
HDD, the Cisco SGSN will generate multiple NodeIds (one for each
internal process generating CDRs), each with its own sequence number.
The number, allocated sequentially and including all CDR types,
is unique within one physical node, which is identified either by
field Node ID or by record-dependent node address (SGSN address, GGSN
address, Record Entity). The local sequence number will be restarted
at 0 when, for example, the node is reloaded.
Note: Since node-id
is unique centralized LRSN feature must be enabled.
Format
Unsigned Integer (0..4294967295)
Length
1–4 Bytes / 1-5
Bytes (custom33)
Location Area Code
(LAC)
This field contains
the location area code (LAC) identifying the location area in which
the served party is currently located. When the (partial) record
is opened. The LAC is coded according to 3GPP TS 24.008.
MS Network Capability
This field identifies
the mobile station network capability value or information element
for the served MS at PDP Context Activation or at GPRS Attach as
defined in 3GPP TS 24.008
Network Initiated
PDP Context
The presence
of this field indicates that the PDP context was initiated by the
network.
Node ID
The identifier
string for the SGSN that had generated the CDR. Node ID, along
with local record sequence number, uniquely identifies a CDR.
On the ASR5K SGSN,
this NodeID field is a printable string of the ndddSTRING format:
- n: The first digit
is the Sessmgr restart counter having a value between 0 and 7.
- ddd: The number of
the sessmgr instance generating the CDR
- STRING: This is a configured
Node-ID-Suffix having any string between 1 to16 characters, defined
using the gtpp attribute node-id command.
If this node-id-suffix
is not configured, the SGSN uses the GTPP context name as the Node-id-suffix
(truncated to 16 characters).
This field is only
included when the option "gtpp attribute local-record-sequence-number"
is configured.
Length
1–20 Bytes / 5-20
Bytes for custom33
PDP Type
The PDP context
type. The PDP types supported by the SGSN are IP or PPP (including IHOSS:OSP).
Format
Hex Value Octet String
Length
2 Bytes
- Value “0” :
PDP type IPv4
- Value “1”:
PDP type IPv6
- Value “2”:
PDP type IPv4v6
pLMNIdentifier
This field defines
the PLMN identity (MCC and MNC) as part of the location information. It
is present only if the option to include PLMN identity has been
set by the operator.
Note: Bits 5-8 of octet
2 contain third MNC digit, or 1111 used as filler when MNC has only
two digits.
QoS Negotiated
QoS Negotiated
indicates the applied QoS accepted by the network.
Note:
- If a pre-release '99-capable
terminal is served, only octets 1 to4 are included.
- The field is defined
with a maximum size of 12 bytes.
- This field is present
in first container of all CDRs.
- In next container this
field is present if there is QOS change.
QoS Requested
The Quality
of Service Requested field contains the QoS desired by the MS at
PDP context activation.
Note:
- If a pre-release '99-capable
terminal is served, only octets 1 to4 are included.
- The field is defined
with a maximum size of 12 bytes.
- This field is present
in first container of all CDRs.
- In next container this
field is present if there is QOS change. Qos Requested field may be
absent if QOS change is initiated by network(GGSN/HLR).
Radio Access Technology
(RAT) Type
The SGSN may
include the RAT Type IE along with User Location Information IE,
and MS Time Zone IE if they are available. The RAT Type IE is not
included for the MS-initiated PDP Context Modification procedure.
Record Extensions
A set of network
operator or manufacturer specific extensions that may be added to
the record if provided. It is used for reporting flows and volumes
consumed, and also for passing key information about the session
into the downstream charging systems.
IMPORTANT:
This field is customer specific.
Record Opening Time
The timestamp
at which the PDP context was activated on the SGSN or when a subsequent record
is opened after a partial record. The timestamp is determined based
on the internal timer which has an accuracy of 10ms. Depending on
the configured mechanism (ceiling, floor, round-off) this is translated into
the timestamp which only shows the full seconds.
Format
BCD Encoded Octet String
Record Sequence
Number
A running sequence
number used to link partial records generated by the SGSN for a
specific PDP context (characterized with the same Charging ID and
SGSN address pair). This field is only present in case of partial
records or if the first record is also the final record.
Record Type
Indicates type
of the record: S-CDR(sgsnPDPRecord) >>> 18 (0x12).
RNC Unsent Downlink
Volume
The downlink
data volume that the RNC has not sent to MS. This field is present
when the RNC has provided unsent downlink volume count at RAB release.
Routing Area Code
(RAC)
This field contains
the Routing Area Code (RAC) of the routing area in which the served
party is currently located when the (partial) record is opened.
The RAC is coded according to 3GPP TS 24.008.
Served IMEI
This field contains
the international mobile equipment identity (IMEI) of the equipment served.
If IMEISV (IMEI softare version) is available, then IMEISV shall
be sent in the CDR. The structure of the IMEI is defined in TS 23.003.
The IMEI is composed
of the following elements:
- Type Allocation Code
(TAC) with a length of 8 digits;
- Serial Number (SNR)
is an individual serial number uniquely identifying each equipment
within each TAC. Its length is 6 digits;
- Spare digit: this digit
shall be zero, when transmitted by the MS
A filler
digit "f" is added after the spare digit to fill up the last byte.
Format
BCD Encoded Octet String
Served IMSI
The International
Mobile Subscriber Identity (IMS) of the MS. The IMSI is formatted
in accordance with 3GPP TS 23.003. This will be present if the Anonymous
Access Indicator is FALSE or not supplied.
Format
BCD Encoded Octet String
Served PDP Address
The binary-represented
IP address associated with the PDP context of the served IMSI for the
CDR. This address could be either static or dynamically assigned.
The standard 3GPP TS32.298 allows a choice of either IPAddress or
ETSIAddress - a binary IPv4 address (iPBINV4Address) or IPv6 address (iPBinV6Address).
Length
4 bytes for IPv4 address
16 bytes for IPv6
address
Served MSISDN
The primary
Mobile Station (MS) ISDN number (MSISDN) of the subscriber.
Format
BCD Encoded Octet String
SGSN Address
The SGSN IPv4
addresses (binary-represented) used over the duration of the CDR.
The address(es) can be either user or control-plane addresses.
Format
Hex Value Octet String
Length
4 Bytes per address,
field max is 30 Bytes
SGSN Change
Present if this
is first record after SGSN change.