Table Of Contents
gprs gtp echo-timer dynamic enable
gprs gtp echo-timer dynamic minimum
gprs gtp echo-timer dynamic smooth-factor
gprs gtp error-indication throttle
gprs gtp ip udp ignore checksum
gprs gtp ppp-regeneration vtemplate
gprs gtp response-message pco ipcp nack
gprs gtp response-message wait-accounting
gprs gtp-director retry-timeout
gprs idle-pdp-context purge-timer
gprs maximum-pdp-context-allowed
gprs qos default-response requested
gprs radius attribute chap-challenge
gprs umts-qos map diffserv-phb
gprs umts-qos map traffic-class
gtp response-message wait-accounting
ip mobile foreign-agent skip-aaa-reauthentication
ip mobile registration-lifetime
ip rtp compression-connections
radius attribute suppress imsi
radius attribute suppress sgsn-address
gprs gtp echo-timer dynamic enable
To enable the dynamic echo timer on the GGSN, use the gprs gtp echo-timer dynamic enable global configuration command. To disable the dynamic echo timer, use the no form of this command.
gprs gtp echo-timer dynamic enable
no gprs gtp echo-timer dynamic enable
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Global configuration
Command History
Usage Guidelines
For a GTP path to be active, the SGSN needs to be active. To determine that an SGSN is active, the GGSN and SGSN exchange echo messages. Although the GGSN supports different methods of echo message timing, the basic echo flow begins when the GGSN sends an echo request message to the SGSN. The SGSN sends a corresponding echo response message back to the GGSN.
If the GGSN does not receive a response after a certain number of retries (a configurable value), the GGSN assumes that the SGSN is not active. This indicates a GTP path failure, and the GGSN clears all PDP context requests associated with that path.
The GGSN supports two different methods of echo timing—the default echo timer and the dynamic echo timer.
The GGSN's default echo timer can not be configured to accommodate network congestion and therefore the GTP path could be cleared prematurely. The dynamic echo timer feature enables the GGSN to better manage the GTP path during periods of network congestion. Use the gprs gtp echo-timer dynamic enable command to enable the GGSN to perform dynamic echo timing.
Default echo timer
The dynamic echo timer is based on the default echo timer in the GGSN. A description of the default echo timer follows as a means of comparison.
The default echo timer configuration uses the following commands:
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gprs gtp n3-requests—Specifies maximum number of times that the GGSN attempts to send a echo-request message. The default is 5 times.
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If the GGSN receives the echo response within the path echo interval (as specified in the gprs gtp path-echo-interval command; default is 60 seconds), it sends another echo request message after 60 seconds (or whatever time was configured in the gprs gtp path-echo-interval command). This message flow continues as long as the GGSN receives an echo response message from the SGSN within the specified path echo interval.
If the GGSN fails to receive an echo response message from the SGSN within the path echo interval, it resends echo request messages until the N3-requests counter is reached (as specified by the gprs gtp n3-requests command; default is 5). Because the initial request message is included in the N3-requests counter, the total number of retries is N3-1. The T3 timer increases by a factor of two for each retry (the factor value is not configurable).
For example, if N3 is set to the default of 5, and T3 is set to the default of 1 second, the GGSN will resend 4 echo request messages (the initial request + 4 retries=5). The T3 time increments for each additional echo request, by a factor of 2 seconds. So, the GGSN resends a message in 2 seconds, 4 seconds, 8 seconds, and 16 seconds. If the GGSN fails to receive an echo response message from the SGSN within the time period of the N3-requests counter, it clears the GTP path and deletes all of the PDP contexts.
For the above example, the total elapsed time from when the first request message is sent, to when the GTP path is cleared, is: 60+2+4+8+16=90 seconds,
where 60 is the initial value of the path echo interval, and the remaining 4 time periods are the increments of the T3 timer for the subsequent retries.
Dynamic echo timer
The dynamic echo timer method is different from the default echo timer method on the GGSN because it uses a calculated round-trip timer (RTT), as well as a configurable factor or multiplier to be applied to the RTT statistic.
The dynamic echo timer configuration uses the following commands:
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The GGSN calculates the RTT statistic for use by the dynamic echo timer feature. The RTT is the amount of time between sending a particular echo request message and receiving the corresponding echo response message. RTT is calculated for the first echo response received; the GGSN records this statistic. Because the RTT value might be a very small number, there is a minimum time for the dynamic echo timer to use. This value is configured using the gprs gtp echo-timer dynamic minimum command.
If the GGSN fails to receive an echo response message from the SGSN within the path echo interval, it goes into retransmission, or path failure mode. During path failure mode, the GGSN uses a value referred to as the T-dynamic. The T-dynamic is the greater of either the dynamic minimum, or the RTT statistic multiplied by the smooth factor.
The T-dynamic essentially replaces the use of the gprs gtp t3-response command, which is used in the default echo timer method on the GGSN. The T-dynamic timer increases by a factor of two for each retry (again, this factor is not configurable), until the N3-requests counter is reached (N3-requests counter includes the initial request message).
For example, if the RTT is 6 seconds, N3 is set to 5, and the smooth factor is set to 3, the GGSN will resend 4 echo request messages in path failure mode. The T-dynamic value is 18 (RTT x smooth factor), so the GGSN sends a retry echo request message in 36 seconds, 72 seconds, 144 seconds, and 288 seconds. If the GGSN fails to receive an echo response message from the SGSN in this time period, it clears the GTP path and deletes all PDP contexts. The total elapsed time from when the first request message is sent to when the GTP path is cleared is: 60+36+72+144+288=600 seconds, where 60 is the initial value of the path echo interval, and the remaining 4 time periods are the increments of the T-dynamic for the subsequent retries.
Examples
The following example turns on the dynamic echo timer, sets the minimum value to 5 seconds, and configures a smooth factor of 3:
gprs gtp echo-timer dynamic enablegprs gtp echo-timer dynamic minimum 5gprs gtp echo-timer dynamic smooth-factor 3Related Commands
gprs gtp echo-timer dynamic minimum
To specify the minimum time period used by the dynamic echo timer, use the gprs gtp echo-timer dynamic minimum global configuration command. To return to the default value, use the no form of this command.
gprs gtp echo-timer dynamic minimum number
no gprs gtp echo-timer dynamic minimum number
Syntax Description
number
Minimum time period (between 1 and 60 seconds) of the dynamic echo timer. Value must be an integer. The default value is 5 seconds.
Defaults
5 seconds
Command Modes
Global configuration
Command History
Usage Guidelines
Use this command to specify the minimum time period (in seconds) used by the dynamic echo timer, also referred to as the T-dynamic. If the GGSN's current calculation of the round-trip timer (RTT) statistic, multiplied by the smooth factor, is less than the configured dynamic minimum value, then the GGSN uses the configured minimum as the T-dynamic.
The GGSN calculates the RTT statistic for use by the dynamic echo timer feature. The RTT is the amount of time between sending a particular echo request message and receiving the corresponding echo response message. RTT is calculated for the first echo response received; the GGSN records this statistic. Because the RTT value might be a very small number, there is a minimum time for the dynamic echo timer to use. This value is configured using the gprs gtp echo-timer dynamic minimum command.
If the GGSN fails to receive an echo response message from the SGSN within the path echo interval, it goes into retransmission, or path failure mode. During path failure mode, the GGSN uses a value referred to as the T-dynamic. The T-dynamic is the greater of either the dynamic minimum, or the RTT statistic multiplied by the smooth factor.
The T-dynamic essentially replaces the use of the gprs gtp t3-response command, which is used in the default echo timer method on the GGSN. The T-dynamic timer increases by a factor of two for each retry (again, this factor is not configurable), until the N3-requests counter is reached (N3-requests counter includes the initial request message).
Note
Examples
The following example turns on the dynamic echo timer, sets the minimum value to 6 seconds, and configures a smooth factor of 2:
gprs gtp echo-timer dynamic enablegprs gtp echo-timer dynamic minimum 6gprs gtp echo-timer dynamic smooth-factor 2Related Commands
gprs gtp echo-timer dynamic smooth-factor
To configure the multiplier that the GGSN uses to calculate the time to wait to send retries of the dynamic echo timer, use the gprs gtp echo-timer dynamic smooth-factor global configuration command. To return to the default value, use the no form of this command.
gprs gtp echo-timer dynamic smooth-factor number
no gprs gtp echo-timer dynamic smooth-factor number
Syntax Description
number
Integer (between 1 and 100) used by the GGSN as a multiplier for the RTT statistic, to calculate the T-dynamic. The default is 2.
Defaults
2
Command Modes
Global configuration
Command History
Usage Guidelines
The dynamic echo timer uses the smooth factor to calculate what is known as the T-dynamic. The T-dynamic is calculated by multiplying the RTT (or the value configured in the gprs gtp echo-timer dynamic minimum, whichever is greater) times the smooth-factor.
Note
Examples
The following example turns on the dynamic echo timer, sets the minimum value to 1 second, and configures a smooth factor of 2:
gprs gtp echo-timer dynamic enablegprs gtp echo-timer dynamic minimum 1gprs gtp echo-timer dynamic smooth-factor 2Related Commands
gprs gtp error-indication throttle
To specify the maximum number of error indication messages that the GGSN sends out in one second, use the gprs gtp error-indication throttle command. To disable the GGSN from sending error indication messages, use the no form of this command.
gprs gtp error-indication throttle window-size size
no gprs gtp error-indication throttle
Syntax Description
size
Integer (between 0 and 256) that specifies the maximum number of error indication messages that the GGSN sends in one second.
Defaults
Disabled
Command Modes
Global configuration
Command History
Usage Guidelines
Use the gprs gtp error-indication throttle command to specify the maximum number of error indication messages that are sent by the GGSN in one second. This provides a way to implement flow control for transmission of GTP error messages. The GGSN maintains a counter that decrements each time that an error indication message is sent. The GGSN resets this counter to the configured throttle value after one second.
If you do not issue the command, error indication throttling is not enabled. To restore the default value (error indication throttling is disabled) use the no form of this command.
Examples
The following example shows a throttle value of 150:
gprs gtp error-indication throttle window-size 150gprs gtp ip udp ignore checksum
To disable verification of the user datagram protocol (UDP) checksum to support CEF switching on the GGSN, use the gprs gtp ip udp ignore checksum global configuration command. To enable UDP checksum verification on the GGSN, use the no form of this command.
gprs gtp ip udp ignore checksum
no gprs gtp ip udp ignore checksum
Syntax Description
This command has no arguments or keywords.
Defaults
UDP checksum verification is enabled on the GGSN.
Command Modes
Global configuration
Command History
Usage Guidelines
UDP checksum verification can prohibit operation of CEF switching processing on the GGSN if the checksum should have a non-zero result. Therefore, if you want to enable CEF switching on the GGSN, you should configure the gprs gtp ip udp ignore checksum command.
If UDP checksum verification remains enabled on the GGSN and a non-zero result occurs, the GTP T-PDUs will be process switched, even if you have configured the GGSN for CEF switching.
The gprs gtp ip udp ignore checksum command does not apply if you are only using process switching on the GGSN.
For more information about switching processes on the router, refer to the Cisco IOS Switching Services Configuration Guide.
Examples
The following example disables UDP checksum verification on the GGSN:
gprs gtp ip udp ignore checksumRelated Commands
gprs gtp map signalling tos
To specify an IP ToS mapping for GPRS tunneling protocol (GTP) signaling packets, use the gprs gtp map signalling tos global configuration command. To return to the default value, use the no form of this command.
gprs gtp map signalling tos tos-value
no gprs gtp map signalling tos tos-value
Syntax Description
Defaults
ToS value 5
Command Modes
Global configuration
Command History
Usage Guidelines
Use the gprs gtp map signalling tos command to specify the IP ToS mapping for GTP signaling packets transmitted by the GGSN. The higher the value, the higher the class of service provided to the packets.
Examples
The following example specifies a IP ToS mapping value of 3:
gprs gtp map signalling tos 3Related Commands
gprs gtp n3-buffer-size
To specify the size of the receive buffer that the GGSN uses to receive GTP signaling messages and packets sent through the tunneling protocol, use the gprs gtp n3-buffer-size global configuration command. To return to the default value, use the no form of this command.
gprs gtp n3-buffer-size bytes
no gprs gtp n3-buffer-size
Syntax Description
bytes
Number of bytes (between 2048 and 65535) that specifies the size of the N3 buffer. The default is 8192 bytes.
Defaults
8192 bytes
Command Modes
Global configuration
Command History
Usage Guidelines
Use the gprs gtp n3-buffer-size command to specify the size of the GTP N3 buffer on the GGSN. The N3 buffer is a receive buffer that the GGSN uses to receive GTP signaling messages and packets sent through the tunneling protocol. The recommended value for the N3 buffer size is 8192 (the default size).
Examples
The following example specifies a buffer size of 2084 bytes:
gprs gtp n3-buffer-size 2048gprs gtp n3-requests
To specify the maximum number of times that the GGSN attempts to send a signaling request to an SGSN, use the gprs gtp n3-requests global configuration command. To return to the default value, use the no form of this command.
gprs gtp n3-requests requests
no gprs gtp n3-requests requests
Syntax Description
requests
A number between 1 and 65535 that specifies the number of times a request is attempted. The default is 5 requests.
Defaults
5 requests
Command Modes
Global configuration
Command History
Usage Guidelines
The value of the gprs gtp n3-requests command is used for all signaling requests on the GGSN.
The GGSN supports two different methods of echo timing—the default echo timer and the dynamic echo timer. The gprs gtp n3-requests command is used by the GGSN to perform either type of echo processing.
Examples
The following example shows the GGSN attempting to send a signaling request 3 times:gprs gtp n3-requests 3Related Commands
gprs gtp path-echo-interval
To specify the number of seconds that the GGSN waits before sending an echo-request message to the SGSN, use the gprs gtp path-echo-interval global configuration command. To return to the default value, use the no form of this command.
gprs gtp path-echo-interval interval
no gprs gtp path-echo-interval interval
Syntax Description
Defaults
60 seconds
Command Modes
Global configuration mode
Command History
Usage Guidelines
The GGSN supports two different methods of echo timing—the default echo timer and the dynamic echo timer. The gprs gtp path-echo-interval command is used on the GGSN to perform either type of echo processing.
Use the gprs gtp path-echo-interval command to specify the interval that the GGSN waits before sending an echo-request message to the SGSN to check for GTP path failure.
Note
Examples
The following example shows the GGSN waiting 90 seconds before sending an echo-request message:
gprs gtp path echo-interval 90Related Commands
gprs gtp ppp vtemplate
To associate the virtual template interface that defines the PPP characteristics with support for the PPP PDP type over GTP on the GGSN, use the gprs gtp ppp vtemplate global configuration command. To remove specification of the PPP virtual template interface for GTP on the GGSN, use the no form of this command.
gprs gtp ppp vtemplate number
no gprs gtp ppp vtemplate number
Syntax Description
Defaults
No default behavior or values.
Command Modes
Global configuration
Command History
Usage Guidelines
Before you configure the gprs gtp ppp vtemplate command, you must configure the virtual template interface with the necessary PPP characteristics. The number that you configure for the virtual template interface that defines the PPP characteristics, must correspond to the number that you specify in the gprs gtp ppp vtemplate command.
Examples
The following example configures two virtual template interfaces on the GGSN, one for GTP encapsulation and one for PPP, and specifies the PPP virtual template interface for GTP on the GGSN.
Note
The first section of commands configures the GPRS virtual template interface for GTP:
interface Virtual-Template 1ip address 10.1.1.1 255.0.0.0no ip directed-broadcastencapsulation gtpno ip route-cachegprs access-point-list gprsThe following example configures a virtual template interface for PPP and associates the virtual template for support of the PPP PDP type over GTP on the GGSN:
interface Virtual-Template 2ip unnumbered FastEthernet 1/0no ip directed-broadcastno peer default ip addressppp authentication chapppp timeout retry 30gprs gtp ppp vtemplate 2Related Commands
interface virtual-template
Creates a virtual template interface that can be configured and applied dynamically in creating virtual access interfaces.
gprs gtp ppp-regeneration vtemplate
To associate the virtual template interface that is configured for PPP encapsulation with support for regenerated PPP sessions on the GGSN, use the gprs gtp ppp-regeneration vtemplate global configuration command. To remove specification of the PPP virtual template interface for regenerated PPP sessions on the GGSN, use the no form of this command.
gprs gtp ppp-regeneration vtemplate number
no gprs gtp ppp-regeneration vtemplate number
Syntax Description
Defaults
No default behavior or values.
Command Modes
Global configuration
Command History
Usage Guidelines
Before you configure the gprs gtp ppp-regeneration vtemplate command, you must configure the virtual template interface for PPP encapsulation using the encapsulation ppp command. In addition, you must also configure the ip address negotiated command and the no peer neighbor-route command at the virtual template interface for PPP encapsulation.
The number that you configure for the virtual template interface to support PPP encapsulation, must correspond to the number that you specify in the gprs gtp ppp-regeneration vtemplate command.
Examples
The following example configures two virtual template interfaces on the GGSN, one for GTP encapsulation for communication between the GGSN and the SGSN, and one for PPP regeneration. The virtual template interface for PPP regeneration supports the creation of PPP sessions from the GGSN over Layer 2 Tunneling Protocol (L2TP) tunnels to an L2TP network server (LNS).
Note
The first section of commands configures the GPRS virtual template interface for GTP:
interface Virtual-Template 1ip address 10.1.1.1 255.0.0.0no ip directed-broadcastencapsulation gtpno ip route-cachegprs access-point-list gprsThe following example configures a virtual template interface for PPP regeneration:
interface Virtual-Template 11ip address negotiatedno peer neighbor-routeencapsulation pppThe following example specifies virtual template interface 11 for PPP regeneration on the GGSN:
gprs gtp ppp-regeneration vtemplate 11Related Commands
interface virtual-template
Creates a virtual template interface that can be configured and applied dynamically in creating virtual access interfaces.
gprs gtp response-message pco ipcp nack
To configure the GGSN to return an IPCP Conf-Nack (Code 03) in the GTP protocol configuration option (PCO) information element (IE) of a create PDP context response when returning IP Control Protocol (IPCP) options for which the granted values (non-zero) differ from those requested (IPCP Conf-Reject [Code 04] for those options for which the returned address values are zero), use the gprs gtp response-message pco ipcp nack global configuration command. To return to the default, use the no form of the command.
gprs gtp response-message pco ipcp nack
no gprs gtp response-message pco ipcp nack
Syntax Description
This command has no arguments or keywords.
Defaults
The GGSN sends an IPCP Conf-Ack (Code 2) in the PCO IE of the create PDP context response for the IPCP options for all the requested IPCP address options supported by the GGSN. The values being returned might be the same as or differ from those requested, or be zero.
For unsupported options, an IPCP Conf-Reject is returned.
Command Modes
Global configuration
Command History
12.3(2)XB1
This command was introduced.
12.3(8)T
This command was incorporated in Cisco IOS Release 12.3(8)T.
Usage Guidelines
Use the gprs gtp response-message pco ipcp nack command to configure the GGSN to return an IPCP Conf-Nack in the PCO IE of a create PDP context response when returning IPCP options for which the granted values differ from those requested.
When the gprs gtp response-message pco ipcp nack command is configured, and the PCO IE of the create PDP context request contains IPCP options, the PCO IE in the create PDP response includes the following, depending on the whether options are supported by (and values are acceptible to) the GGSN:
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gprs gtp response-message wait-accounting
To configure the GGSN to wait for a RADIUS accounting response before sending a create PDP context response to the SGSN, for create PDP context requests received across all access points, use the gprs gtp response-message wait-accounting global configuration command. To configure the GGSN to send a create PDP context response to the SGSN after sending a RADIUS start accounting message to the RADIUS server (without waiting for a response from the RADIUS accounting server), use the no form of this command.
gprs gtp response-message wait-accounting
no gprs gtp response-message wait-accounting
Syntax Description
This command has no arguments or keywords.
Defaults
The GGSN sends a create PDP context response to the SGSN after sending a RADIUS start accounting message to the RADIUS accounting server. The GGSN does not wait for a RADIUS accounting response from the RADIUS accounting server.
Command Modes
Global configuration
Command History
Usage Guidelines
Use the gprs gtp response-message wait-accounting command to configure the GGSN to wait for a RADIUS accounting response from the RADIUS accounting server, before sending a create PDP context response to the SGSN, for create PDP context requests received across all access points.
If the GGSN does not receive a response from the RADIUS accounting server when you have configured the gprs gtp response-message wait-accounting command, then the GGSN rejects the PDP context request.
The GGSN supports configuration of RADIUS response message waiting at both the global and access-point configuration levels. You can minimize your configuration by specifying the configuration that you want to support across most APNs, at the global configuration level. Then, at the access-point configuration level, you can selectively modify the behavior that you want to support at a particular APN. Therefore, at the APN configuration level, you can override the global configuration of RADIUS response message waiting.
To configure the GGSN to wait for a RADIUS accounting response as the default behavior for all APNs, use the gprs gtp response-message wait-accounting global configuration command. To disable this behavior for a particular APN, use the no response-message wait-accounting access-point configuration command.
To verify whether RADIUS response message waiting is enabled or disabled at an APN, you can use the show gprs access-point command and observe the value reported in the wait_accounting output field.
Examples
The following example globally configures the GGSN to wait for a RADIUS accounting response from the RADIUS accounting server before sending an activate PDP context response to the SGSN, for PDP context requests received across all access points except access-point 1. RADIUS response message waiting has been overridden at access-point 1 using the no gtp response-message wait-accounting command:
Note
aaa new-model!aaa group server radius fooserver 10.2.3.4server 10.6.7.8!aaa authentication ppp foo group fooaaa authorization network default group radiusaaa accounting exec default start-stop group foo!gprs access-point-list gprsaccess-point 1access-mode non-transparentaccess-point-name www.pdn1.comaaa-group authentication foono gtp response-message wait-accountingexitaccess-point 2access-mode non-transparentaccess-point-name www.pdn2.comaaa-group authentication foo!gprs gtp response-message wait-accounting!radius-server host 10.2.3.4 auth-port 1645 acct-port 1646 non-standardradius-server host 10.6.7.8 auth-port 1645 acct-port 1646 non-standardradius-server key ggsntelRelated Commands
gprs gtp t3-response
To specify the initial time that the GGSN waits before resending a signaling request message when a response to a request has not been received, use the gprs gtp t3-response global configuration command. To return to the default value, use the no form of this command.
gprs gtp t3-response response-interval
no gprs gtp t3-response response-interval
Syntax Description
response-interval
A value between 1 and 65535 that specifies the length of the T3 response interval, in seconds. The default is 1 second.
Defaults
1 second
Command Modes
Global configuration
Command History
Usage Guidelines
The gprs gtp t3-response command is used by the GGSN to process delete PDP context requests and to perform the default method of echo timing.
For delete PDP context requests, the gprs gtp t3-response command is used by the GGSN to specify how long the GGSN waits before sending a retry of the delete PDP context request when a response is not received from the SGSN, until the gprs gtp n3-requests limit is reached.
The GGSN supports two echo timer implementations—the default echo timer and the dynamic echo timer. The gprs gtp t3-response command also is used on the GGSN to perform the default type of echo processing, when the dynamic echo timer is not enabled.
If the GGSN receives the echo response within the path echo interval (as specified in the gprs gtp path-echo-interval command; default is 60 seconds), it sends another echo request message after 60 seconds (or whatever time was configured in the gprs gtp path-echo-interval command). This message flow continues as long as the GGSN receives an echo response message from the SGSN within the specified path echo interval.
If the GGSN fails to receive an echo response message from the SGSN within the path echo interval, it resends echo request messages until the N3-requests counter is reached (as specified by the gprs gtp n3-requests command; default is 5). Because the initial request message is included in the N3-requests counter, the total number of retries is N3-1. The T3 timer increases by a factor of two for each retry (the factor value is not configurable).
For example, if N3 is set to the default of 5, and T3 is set to the default of 1 second, the GGSN will resend 4 echo request messages (the initial request + 4 retries=5). The T3 time increments for each additional echo request, by a factor of 2 seconds. So, the GGSN resends a message in 2 seconds, 4 seconds, 8 seconds, and 16 seconds. If the GGSN fails to receive an echo response message from the SGSN within the time period of the N3-requests counter, it clears the GTP path and deletes all of the PDP contexts.
For the above example, the total elapsed time from when the first request message is sent, to when the GTP path is cleared, is: 60+2+4+8+16=90 seconds,
where 60 is the initial value of the path echo interval, and the remaining 4 time periods are the increments of the T3 timer for the subsequent retries.
Examples
The following example shows a T3 interval response interval of 524 seconds:
gprs gtp t3-response 524Related Commands
gprs gtp-director retry-timeout
To specify the amount of time during which GDM forwards all retries of create PDP context requests for a specific TID from an SGSN to the same GGSN, use the gprs gtp-director retry-timeout global configuration command. To return to the default value, use the no form of this command.
gprs gtp-director retry-timeout seconds
no gprs gtp-director retry-timeout seconds
Syntax Description
seconds
Number of seconds (between 1 and 65535) during which GDM forwards retries for a specific TID to the same GGSN. The default is 30 seconds.
Defaults
30 seconds
Command Modes
Global configuration
Command History
Usage Guidelines
Use the gprs gtp-director retry-timeout command only when configuring the GTP Director Module (GDM). Do not configure this command on a GGSN.
Use the gprs gtp-director retry-timeout command to specify how long GDM forwards all retries of create PDP context requests for a specific TID from an SGSN to the same GGSN. The retry-timeout value represents the maximum period of time during which GDM expects the real GGSN to establish or reject the PDP context request.
It is recommended that the retry-timeout value be specified according to the following formula:
,
where
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•
•
•
Note
Examples
The following example configures GDM to forward all retries of create PDP context requests for a specific TID to the same GGSN for 1 minute:
gprs gtp-director retry-timeout 60Related Commands
gprs idle-pdp-context purge-timer
To specify the time that the GGSN waits before purging idle mobile sessions, use the gprs idle-pdp-context purge-timer global configuration command. To return to the default value, use the no form of this command.
gprs idle-pdp-context purge-timer hours
no gprs idle-pdp-context purge-timer hours
Syntax Description
hours
Value between 0 and 255 that specifies the number of hours that the GGSN waits before purging idle sessions. The value 0 disables the purge timer. The default is 72 hours.
Defaults
72 hours
Command Modes
Global configuration
Command History
