Capability to Record and Produce Call Transactions

Feature Summary and Revision History

Summary Data

Applicable Product(s) or Functional Area

ePDG

Applicable Platform(s)

  • ASR 5500

  • VPC-DI

  • VPC-SI

Feature Default

Disabled - Configuration Required

Related Changes in This Release

Not Applicable

Related Documentation

ePDG Administration Guide

Revision History

Revision Details

Release

Added RTT Record Schema table.

21.26

ePDG supports capability to record and produce call transactions.

21.23

First Introduced.

Release 20

Feature Description

Real Time Tool (RTT) is used in Regions and Network Operations Center (NOC) for debugging network issues and to understand user behavior. All call transactions in ePDG are generated in RTT files. The ePDG support allows to understand service impact on the ePDG chassis for WLAN offload service. ePDG transfers RTT files to the external server through SSH File Transfer Protocol (SFTP). The RTT files that are in comma separated values (.CSV) format are transferred either in compressed or non-compressed format based on the configuration to the external servers such as servers in customer network either directly or through the Cisco Collector server.


Note


RTT Record Schema and its procedure numbers are genericized to Gateway RTT. Contact your Cisco account representative for detailed information on specific RTT Record Schema.


How It Works

This section describes the RTT procedures and schema.

RTT Procedures

The following table lists the RTT procedures that are specific to ePDG, P-GW and SaMOG:

Procedure Number Procedure Name

Applicability

1

S5/S8/S2b GTP Create Session

P-GW, ePDG, SaMOG

2

S5/S8/S2b GTP Create Bearer

P-GW, ePDG, SaMOG

3

S5/S8/S2b GTP Delete Session

P-GW, ePDG, SaMOG

4

S5/S8/S2b GTP Delete Bearer

P-GW, ePDG, SaMOG

5

GTP Modify Bearer

P-GW

6

S5/S8/S2b GTP Update Bearer

P-GW, ePDG, SaMOG

7

S6b/SWm – Diameter AAR/ AAA

P-GW, ePDG, SaMOG

8

S6b/SWm – Diameter RAR/RAA

P-GW, ePDG, SaMOG

9

S6b/SWm – Diameter Session Termination

P-GW, ePDG, SaMOG

10

S6b/SWm – Abort Session

P-GW, ePDG, SaMOG

11

Diameter Gx – CCR-I/CCA-I

P-GW

12

Diameter Gx – CCR-U/CCA-U

P-GW

13

Diameter Gx – CCR-T/CCA-T

P-GW

14

Diameter Gx – RAR/RAA

P-GW

15

Diameter Gy – CCR-I/CCA-I

P-GW

16

Diameter Gy – CCR-U/CCA-U

P-GW

17

Diameter Gy – CCR-T/CCA-T

P-GW

18

Diameter Gy – RAR/RAA

P-GW

19

PMIPv6 S2a – Binding Update/Acknowledgement

P-GW

20

PMIPv6 S2a Revocation Update/Acknowledgement

P-GW

21

SWu – IKEv2 SA INIT/Resp

ePDG

22

SWu – IKEv2 Auth Req/Resp

ePDG

23

SWu – IKEv2 Information Req/Resp

ePDG

24

SWm – Diameter EAP Request/Answer

ePDG, SaMOG

25

ePDG Router Advertisement

ePDG, SaMOG

26

SWu – CREATE_CHILD_SA Req/Resp

ePDG

27

Radius – WLC-SaMOG Access Request/Challenge

SaMOG

28

Radius – WLC-SaMOG Access Request/Accept

SaMOG

29

Radius – WLC-SaMOG Disconnect Request/Response

SaMOG

30

Radius – WLC-SaMOG Accounting Request/Response

SaMOG

31

Radius – SaMOG-Radius Server Accounting Req/Res

SaMOG

32

WLC – SaMOG DHCP Discover/Offer

SaMOG

33

WLC – SaMOG DHCP Request/Ack/Nak

SaMOG

34

WLC – SaMOG DHCP Release/Ack/Nak

SaMOG

RTT Record Schema

The following figure details the new RTT schema.

Figure 1. RTT Record Schema

RTT schema has a Header and the following six blocks of Information Elements (IEs). There are totally 170 IEs that are grouped in 6 blocks. Contact your Cisco account representative for the complete list of RTT Record Schema IEs.

  • Common IEs

  • GPRS Tunneling Protocol (GTP) IEs. These IEs are existing and are re-used.

  • Diameter IEs (new IEs)

  • Proxy Mobile IPv6 IEs

  • Internet Key Exchange (IKE)/ Internet Protocol Security (IPsec) IEs

  • Internet Protocol v6 Router Advertisement (IPv6 RA IEs


Note


IKE/IPSec and IPv6 RA IEs are new and they are contained inside new blocks. Diameter IEs are new and are appended to the existing Diameter IE blocks.


The RTT Record schemas are listed in the following table:

Table 1.

IE

Description

Format Example

Relevant Procedures

1

Gateway RTT Record Number

Counter in <proclet-type> | <instance-id> | <RTT-record-#>

All

2

Gateway RTT Version Number

Version 3 in R20.0

All

3

Procedure Number

Defined in CFS Table 1

All

4

Gateway Name

Host Name of the Chassis

All

5

Procedure Start Time (GMT)

Time in UTC, (to ms accuracy)

All

6

Procedure End Time (GMT)

Time in UTC, (to ms accuracy)

All

7

ASR5K CallID

Internal CallID, for example [376efb10]

All

8 to 10

Reserved

11

IMSI

Example [311480076488840]

1 11 12 13 22 24

12

MSISDN

Example [19728256305]

1 5 7 15 16 17

13

IMEISV

Example [9900028823793406]

1 11 15

14

TAI - MCC/MNC/TAC

Example string [311-480-0x3B00]

1 through 6 11 12 15 16

15

Cell ID

ECI. Example [0xE70D01]

1 through 6 11 12 15 16

16

ASR5K Disconnect Reason

Internal reason for session disconnect (Example: timeout, error).

All (pending error)

17 to 20

Reserved

21

Serving Network

MCC MNC. Example [311480]

1 5

22

Radio Access Technology

Defined in TS29.274, example [6 = E-UTRAN]

22

23

Handover Indicator

HI field in Indication attribute; example [0 = New PDN; 1 = Handover]

1 5

24

SGW/HSGW/ePDG TEID

Tunnel Identifier for Peer. Example [0x26B609F0]

1 2 5

25

PGW TEID

Tunnel Identifier for PGW. Example [0x084BC005]

1 2

26

AN GW Address

IP Address of Remote GW: HSGW or SGW

1 2 5

27

Access Point Name

String, example:

[Customerims.mnc311.mcc480.3 gppnetwork.org]

1

28

Framed-IP Address

UE assigned IPv4 address

1 11 12 13

29

Framed-IPv6 Address

UE assigned IPv6 prefix/address

1 11 12 13

30

Uplink AMBR

In Kbps; example [0-4294967295]

1 6

31

Downlink AMBR

In Kbps; example [0-4294967295]

1 6

32

PCO DNS IPv6 Address – Primary

IPv6 Address of Primary DNS server

1

33

PCO DNS IPv6 Address – Secondary^Tertiary

Secondary IPv6 Address ^ Tertiary IPv6 Address for DNS

1

34

PCO DNS IPv4 Address – Primary

IPv4 address

1

35

PCO DNS IPv4 Address - Secondary

Secondary IPv4 Address ^ Tertiary IPv6 Address for DNS

1

36

List of EPS Bearer IDs (Successful

Each bearer Id shall be separated by a “|”

Example 1 | 3 | 5

1 2 4 5 6

37

Linked Bearer Identity

Based on TS29.274, example [0-15]

2 3 4 5

38

Uplink MBR

In Kbps. MBR. Example 1234 | 3456 | 567

MBR of each bearer shall be separated by "|” and has the same order as of IE 37

1 6

39

Downlink MBR

Same as Uplink MBR

1 6

40

Uplink GBR

In Kbps. GBR. Example 1234 | 3456 | 567

MBR of each bearer shall be separated by "|” and has same order as of IE 37

1 6

41

Downlink GBR

Same as Uplink GBR

1 6

42

GTP Cause Value

Based on TS29.274 Request/Acceptance/Rejection Cause, example [1-255]

1 to 6

43

Piggyback Record Indicator

Explicit indication of piggyback message record, example (0=no; 1=yes)

2 5

44 to 50

Reserved

51

Session ID

Session-ID for Authentication Session, example,

UTF8 String [0006-diamproxy.WSBOMAGJPNC. S6b.vzims.com; 21604107; 449305093; 536f9359-503]

7 to 18 24

52

Auth-Application ID

Example [S6b = 16777999 , Gx = 16777238, Gy = 4]

7 to 18 24

53

PGW-Host (Origin Host)

FQDN of PGW, example [0004-diamproxy. WSBOMAGJPNC. Gy.vzims. com]

7 to 18 24

54

Diameter Peer Address Realm

FQDN of 3GPP AAA, PCRF OCS realm, example [Customerims.com]

7 to 18 24

55

Dest Peer Host

FQDN of 3GPP AAA, PCRF, OCS host, example [njbbpcrf1a.vzims.com]

7 to 18 24

56

CC Request Type

Example Enumerated [1-3, for I, U, T]

11 12 13 15 16 17

57

CC Request Number

Example [0]

11 12 13 15 16 17

58

Result Code

Diameter Result Code based on RFC3588, example [2001]

7 to 18 24

59

Origin State ID

Example [1366695723]

7 to 18

60

Service-Selection

AVP used for providing APN name for authorization, example [Customerinternet]

12 24

61

Charging Gateway Function Host

FQDN of CGF, example [cgf1.NEE29.vzims.com]

5 7

62

Charging Group ID

Charging ID of each bearer shall be separated by “|” in the order same as that of IE 37 followed by 44

5 7

63

Server-Name (CSCF Address)

Only on IMS APN, example [pcscf1.CTX07.vzims.com]

7

64

Framed-pool

Pool name from which IPv4 address is to be allocated, example [int41]

7

65

Framed-IPv6-Pool

Pool name from which IPv6 prefix is to be allocated, example [ims61]

7

66

Auth-Request-Type

Based on TS29.273 and 29.212. Example Enumerated [1-3]

7 24

67

Re-Auth-Request-Type

Based on TS29.273 and 29.212. Example Enumerated [0-1]

8 14 18

68

Diameter Termination Cause

Based on TS29.273 and 29.212. Example Enumerated [1-8]

9 13 17

69

QoS Class Identifier

QCI, example [8]

11 12 15 16

70

IP-CAN Type

Example [5 = 3GPP-EPS]

11 12 14

71

Event Trigger

Based on TS29.212, Series of Pipe Delimited Triggers, example [1 = QOS_CHANGE]

11 12

72

Reserved IE / Unused

73

Charging-Rule-Remove

Name of the removed Charging rule, example String [RTRRule3300]

12

74

Charging-Rule-Install

Name of the installed Charging rule, example String[RTRRule3300]

11

75

Multiple Services Indicator

Based on TS32.299, example Enumerated [0-1]

15 16 17

76

Multiple Services Credit Control Rating-Group

Identifier of Rating Troup, example [3300]

15 16 17

77

Multiple Services Credit Control Granted Service Unit

CC-Total-Octets, example [524288000]

15

78

Reserved

79

Reserved

80

Reserved

81

EAP Auth-Session-State

Example: STATE_MAINTAINED (0)

24

82

WLAN User-Name

Example: 0311150123456701@ wlan.mnc150. mcc311.3 gppnetwork.org

24

83

RAT Type

Example: 0 = WLAN

24

84

Visited Network Identifier

Example: mnc150.mcc311.3gppnetwork.org

24

85

EAP-Master-Session-Key

MSK

24

86

APN Configuration

PDN-Type | Service = Selection | Gateway

24

87 to 90

Reserved

91

MAG IP Address

MAG IP Address

19 20

92

LMA IP Address

LMA IP Address

19 20

93

IMSI-NAI

Example:. 6311480000021024@nai.epc. mnc480. mcc311.3 gppnetwork.org

19 20

94

Service Selection Mobility Option

Set to EPS APN Name, formatted as 3GPP TS 23.003, example, Customerims

19 20

95

Home Network Prefix Option

Dynamic or Static Prefix assigned plus IID allocated for UE

19 20

96

IPv4 Address Request

Address/Prefix, example. 1.1.1.1/32

19

97

IPv4 Address Acknowledgement

Status:Address/Prefix, example. 0:1.1.1.1/32

19

98

IPv4 Default Router

IPv4 Address, example. 2.2.2.2

19

99

Uplink GRE key

Hex, e.g. 0x004D90CC

19

100

Downlink GRE key

Hex, example. 0xCC904D00

19

101

Charging Characteristics

Hex, example. 0x0A

19

102

Charging ID

Hex, example. 0x5E9BD665

19

103

Serving Network

MCC-MNC

19

104

Base Station ID

Hex, example. 001C0001008A

19

105

MEID

Decimal String, example. 99000044001930

106

Binding Sequence #

16 bit unsigned integer for Binding Update and Ack

19

107

Lifetime

16 bit unsigned integer representing ime before binding unit is considered expired. Example. 0x0708

19

108

Handoff Indicator Option

HO Indicator

Example. 0x01 = new attachment

19

109

Access Technology Type (ATT)

Example. 0x09 = eHRPD

19

110

Proxy Binding Status

8-bit unsigned integer indicating status of BU processing.

19

111

PCO DNS IPv6 Address

DNS IPv6 Address. if multiple, format = “Addr1|Addr2”

19

112

PCO DNS IPv4 Address

DNS IPv4 Address. if multiple, format = “Addr1|Addr2”

19

113

P-CSCF Address

P-CSCF IPv6 Address (if multiple, format = “Addr1!Addr2”

19

114

Binding Revocation Status

8-bit unsigned integer indicating result of processing BRI. Values less than 128 indicates success

20

115

Binding Revocation Sequence #

Sequence number to match BRI and BRA messages

20

116

Revocation Trigger

8-bit unsigned integer indicating per UE or global reasons for trigger

20

117

Revocation Flag

Hex, example. 0x4

20

118 to 130

Reserved

131

UE IP Address

UE IP address

21 22 23 26

132

UE UDP Port for SA_INIT

UE UDP Source Port for SA_INIT

21 22 23 26

133

ePDG Address

ePDG IP address for SA_INIT

21 22 23 26

134

ePDG Port

ePDG UDP Port for SA_INIT (example: 4500 for IKE)

21 22 23 26

135

Initiator SPI

Initiator (UE) SPI

21 22 26

136

Responder SPI

Responder (ePDG) SPI

21 22 26

137

Transform Header Type and ID

TypeID negotiated value is entered.

x|y|z|w|U (Enc/prf/Integrity/Dhg/ESN)

In case value is not negotiated, then -1 is entered. Example: PRF is not present in IKE_Auth.

Value will be IANA standard number for these protocols.

21 22 26

138

KE DH Group

Diffie Hellman Group Number

21 26

139

Notify Message Type

Example: NAT_Detection IP Type (delimited as necessary) will be delimited as x|y|z^a|b|c where x/y/z are notify in Procedure request and a/b are notify in Procedure response. If either Request or Response doesn't have any Notify, it will be blank either before or after the delimiter ^.

21 26

140

IDi

Identification Initiator: RFC822 Address, example: 0311150123456701@wlan.mnc150. mcc311. 3gppnetwork.org

22

141

IDr

Identification Responder: IKEv2 FQDN ID, example: apncf.w-apn. mnc150.mcc311. pub. 3gppnetwork.org

22

142

TSi

Protocol Type|Address Range|Port Range

(Can be delimited by ^ if more than one TS)

22

143

TSr

Protocol Type|Address Range|Port Range

(Can be delimited by ^ if more than one TS)

22

144

EAP Message Status Code

Example:. SUCCESS

This will assume last value in the response

22

145

EAP Message Identifier

EAP Message Identifier

22

146

EAP Type

Example: AKA (0x17) for ePDG EAP-AKA (0x17)

22

147

Configured Attribute Auth Method

Shared Key as String. Example: local_method|remote_method where local/remote could be PSK/EAP/CERT

22

148

IKEv2 Config Attribute Internal IP4/IPv6

Example: UE address x^y where x is IPv4 and y is IPv6

22

149

IKEv2_CFG_ ATTRIBUTE_INTERNAL_ IP4_NETMASK

Example: 255.255.255.255

22

150

IKEv2_CFG_ ATTRIBUTE_ INTERNAL_DNS_ IPV4

x^y^z where x,y,z will be IPv4 address. Maximum of 3 entries possible in IKE_Auth_reply.

22

151

IKEv2_CFG_ ATTRIBUTE_ INTERNAL_DNS_ IPV6

x^y^z where x,y,z will be IPv6 address. Maximum of 3 entries possible in IKE_Auth_reply.

This IE is missing. New one needs to be added

22

152

P-CSCF IPv4

x^y^z where x,y, z will be IPv4 address. Maximum of 3 entries possible in IKE_Auth_reply.

153

P-CSCF IPv6

x^y^z where x,y,z will be IPv6 address. Maximum of 3 entries possible in IKE_Auth_reply.

22

154

SA Protocol ID

Example: ESP (0x03)

22

155

SA SPI UE

Example: 0x020000BA

22

156

SA SPI ePDG

Similar to SA SPI UE. This is missing. Needs to be added

157

Informational Request Type

Delete, DPD, and so on.

23

158

IKEv2 Notify – Error Codes

Reference IKEv2 standard Error Codes and Customer Custom Codes per SWu Call Flow: Finally received /sent Notify error code is updated. This could be the Verison custom code if configured, or standard code otherwise.

21 22 23 26

159 to 160

Reserved

161

IPv6 Advertised Prefix

Advertised IPv6 Prefixes as part of Router Advertisement

25

162 to 170

Reserved

Capacity and Performance

When a chassis runs in peak traffic, around 10% of the performance impact is observed while generating RTT records. Depending on the memory, an approximately 40kb zip file will be generated for 10 subscribers and transferred to the server. Based on the RTT record intervals are configured (example: 5 minutes, 10 minutes), all the subscriber records within that time period will be accumulated into a zip file and transferred.

Limitations

  • When the ePDG handles any corrupted packet, it will not be able to create a RTT record as it is being rejected at the NPU level (lower layer).

  • Statistics recovery is out of scope as per the current implementation.

  • RTT record generation during Session Recovery or Card Migration is not supported.

  • RTT records will not be generated for re-transmitted messages.

  • All module configurations (EDR/UDR/EVENT/DIAMETER/HEXDUMP/CELLTRACE) should be part of the same context.

  • When multiple retries are configured, only one RTT record will be generated during retry scenarios. The RTT record will be generated after the final retry.

  • Only details specific to the RTT record size will be provided, based on which the customer shall dimension the external collection server.

  • Session Recovery: During Session Recovery, some control messages may be lost, and the corresponding RTT records will also be lost or not generated. In case the CDRMOD task gets terminated, it simply respawns, and anything it has not written on RAMFS is lost, even though the session manager statistics show that the RTT record has been generated.

  • ICSR: RTT records generation with ICSR is not supported.

  • Card Migration: During DPC migration, CDRMOD is stopped on the old DPC and restarted on the new DPC. As a result, there is a chance of losing RTT records during card migration.

Configuring RTT for ePDG

This section provides RTT configuration information for ePDG.

Enabling RTT to Record and Produce Call Transactions

Use the following configuration for enabling RTT to record and produce call transactions.

configure 
            context context_name 
              epdg-service service_name 
                [ no ] reporting-action event-record 
            end 

NOTES:

  • reporting-action event-record : Enables event reporting through RTT in ePDG.

  • no : Disables event reporting through RTT in ePDG.

Configuring RTT

Use the following CLI commands to configure the RTT feature in ePDG.

configure 
            context context_name 
              session-event-module 
                event transfer-mode push primary url URL_address 
                file name file_name|rotation volume volume_size|rotation time rotation_time|compression compression_type|extension extension_type 
                event use-harddisk 
                event remove-file-after-transfer 
                event push-interval interval_time 
                event purge time-limit seconds 
                event purge storage-limit megabytes      
             end 

NOTES:

  • transfer-mode : Enables the transfer mode in RTT.

  • push primary url : Specifies the external server location where the records are transferred from ePDG.

  • file name : Specifies the RTT file name where the records are stored.

  • rotation volume: The volume based on which the RTT file is generated.

  • rotation time: The time based on which the RTT file is generated.


    Note


    The RTT files are pushed to the external server based on the rotation volume or rotation time, whichever occurs first.


  • compression: Specifies the file compression type. If enabled, the RTT file is generated as a Gzip file, else it is generated as a normal file.

  • extension: Specifies the RTT file extension (.csv).

  • use-harddisk: Specifies hard disk as the storage space for the RTT file generation.

  • remove-file-after-transfer: Specifies RTT files to be removed after pushing the files to the external server.

  • push-interval: Specifies the push interval time at which the RTT file are transferred from ePDG to the external server.

  • purge time-limit: Specifies the time to delete internal files when external server is down.

  • purge storage-limit: Specifies the storage limit to delete internal files when external server is down.

Monitoring and Troubleshooting

This section provides information on how to monitor and troubleshoot using show commands to support this feature.

Show Commands and Output

This section provides information regarding show commands and their outputs for this feature.

show Event-Record Statistics ePDG

This command displays the number of RTT record types generated based on different event types.

Table 2. show event-record statistics ePDG Command Output Descriptions
Field Description

Total Number of Event Records

The total number of event records (GTPv2 + Diameter + IKE + RA).

GTPv2 Event Records

The total number of GTPv2 records

CSR

The total number of CSR (Create Session Request) events.

CBR

The total number of CBR (Create Bearer Request) events.

DSR

The total number of DSR (Delete Session Request) events.

DBR

The total number of DBR (Delete Bearer Request) events.

UBR

The total number of UBR (Update Bearer Request) events.

IKEv2 Event Records

The total number of IKE events.

IKE_SA_INIT

The total number of IKE_SA_INIT events.

IKE_AUTH

The total number of IKE_AUTH events.

IKE_INFORMATION

The total number of IKE_INFORMATION events.

CREATE_CHILD_SA

The total number of CREATE_CHILD_SA events.

IPV6 RA Event Records

The total number of IPV6 RA event records.

RA Prefix

The total number of RA prefix events.

Diameter Event Records

The total number of Diameter event records.

SWm Procedures

The total number of SWm interface specific events.

AAR

The total number AAR (AA-Request) events.

RAR

The total number of RAR (Re-Auth-Request) events

ASR

The total number of ASR (Abort Session Request) events

STR

The total number of STR (Session Termination Request) events.

DER

The total number of DER (DE-Request) events.