Configuring ISG IPv6 Support

Intelligent Services Gateway (ISG) is a software feature set that provides a structured framework in which edge devices can deliver flexible and scalable services to subscribers. This module describes the IPv6 support available for ISG IP subscriber sessions including information about the Time-Based Billing feature.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Restrictions for ISG IPv6 Support

  • Layer 2 connected interfaces are not supported. Only Layer 3 routed in-band IPv6 sessions are supported.

  • Out-of-band IPv6 sessions are not supported, which means DHCP initiated or RADIUS proxy initiated sessions are not supported for IPv6 sessions.

  • Time-based billing is not supported on PPP sessions directly; it is supported through services and flows installed on the PPP session.

Information About ISG IPv6 Support

ISG IPv6 Session Support

ISG creates an IPv6 subscriber session based on the first IPv6 packet received from an unclassified IPv6 address or IPv6 prefix, similar to the way subscriber sessions are created for IPv4 packets. The subscriber session is identified by the IPv6 address. Native IP sessions have either an IPv4 or IPv6 address, but not both. A native IPv6 session has an IPv6 address only and all traffic generated from the subscriber uses IPv6.

IPv6 single-stack sessions are supported for ISG subscriber sessions. If a native IP subscriber’s host sends traffic for both an IPv4 and IPv6 address, ISG creates a separate IP session for each of these IP addresses. This subscriber will have an IPv4 session and an IPv6 session with no interaction between them. A dual-stack session is a single subscriber session with two distinct IP addresses, one for IPv4 and one for IPv6. Dual-stack native IP sessions are not supported.

Layer 3 unclassified IPv6 sessions for routed subscribers are supported. These sessions are identified by their unique IPv6 IP address or an IPv6 subnet session (IPv6 address and prefix). IPv6 is not supported for Layer 2 connected and DHCP-initiated subscriber sessions.

Session Coexistence on ISG Interfaces

The following session combinations can exist on the same ISG interface in Cisco IOS XE Release 3.5S and later releases:

  • Native IPv6 and native IPv4 sessions

  • Native IPv6 and PPP IPv4 sessions

  • Native IPv6 and PPP IPv6 sessions

  • Native IPv6 and PPP dual-stack sessions

ISG Dual-Stack Features

Dual-stack features are protocol independent and work at the session level. These features cannot be configured based on the stack. A single generic configuration is applied to the session regardless of whether it is a single-stack or dual-stack session. The configuration of these features is the same for IPv4 and IPv6.

Because these features are applied at the session level, the same instance of the feature handles both the IPv4 and IPv6 stacks for a dual-stack session, and the behavior is aggregated. For example, the same instance of the accounting feature counts both IPv4 and IPv6 packets. Similarly, the same instance of the idle timeout feature monitors both IPv4 and IPv6 traffic and considers a session to be idle when there is neither type of traffic.

The following features are examples of dual-stack features:

  • Absolute Timeout (Session Timer)

  • Idle Timeout (Connection Timer)

  • ISG Accounting

  • ISG Policer (Dynamic Rate Limiting)

  • Quality of Service

ISG Protocol-Dependent Features

Protocol-dependent features rely on the underlying protocol. An instance of the feature works only for one of the protocols, either IPv6 or IPv4. For example, the Layer 4 Redirect feature has translation rules that are protocol dependent. An IPv6 packet can be redirected only to an IPv6 destination; an IPv4 packet can be redirected only to an IPv4 destination.

The configuration of protocol-dependent features applies only to the corresponding stack of the session. If a feature must run on both protocols for a dual-stack session, separate configurations must be created and applied on both stacks respectively. These features cannot be configured for an entire session unless it is a single-stack session.

The behavior of protocol-dependent features is limited to a single stack. An instance of the feature runs only on a particular stack and has no functional impact on the other stack, if applicable. If the feature is applied on both stacks of a dual-stack session, two separate instances are created and run independently. There is no aggregated behavior for these features.

The following features are examples of ISG protocol-dependent features:

  • Access Control Lists (ACLs)

  • Layer 4 Redirect

  • Port-Bundle Host Key

  • Traffic Classes

IPv6 Support for ISG Features

The following ISG features are supported for native IPv6 sessions and PPP dual-stack sessions:

Feature

Description

Session Support

Absolute Timeout (Session Timer)

IPv6 functionality and configuration are the same as for IPv4 subscriber sessions.

For configuration information, see the “Configuring ISG Policies for Session Maintenance” module in this guide.

  • Native IPv4/IPv6

  • PPP dual stack

Idle Timeout (Connection Timer)

IPv6 functionality and configuration are the same as for IPv4 subscriber sessions.

For configuration information, see the “Configuring ISG Policies for Session Maintenance” module in this guide.

  • Native IPv4/IPv6

  • PPP dual stack

ISG Accounting

Per-session and per-service accounting can be configured on either an IPv4-only or IPv6-only IP session. Per-flow accounting can be configured on either an IPv4 or IPv6 traffic class.

For configuration information, see the “Configuring ISG Accounting” module in this guide.

  • Native IPv4/IPv6

  • PPP dual stack

ISG Policer (Dynamic Rate Limiting)

IPv6 functionality and configuration are the same as for IPv4 subscriber sessions.

For information, see the “Configuring MQC Support for IP Sessions” module in this guide.

  • Native IPv4/IPv6

  • PPP dual stack

Layer 4 Redirect

IPv6 packets can be redirected only to an IPv6 destination; IPv4 packets can be redirected only to an IPv4 destination.

For configuration information, see the “Redirecting Subscriber Traffic Using ISG Layer 4 Redirect” module in this guide.

  • Native IPv4/IPv6

  • PPP dual stack

  • Protocol dependent

Modular QoS CLI (MQC)

The following operations are supported for an MQC policy applied to PPP IPv6 sessions and PPP dual-stack sessions:

  • Add or remove a class

  • Add, remove, or modify an action under a class

  • Modify an ACL

For configuration information, see the “Configuring MQC Support for IP Sessions” module in this guide.

  • Native IPv4

  • PPP IPv6

  • PPP dual stack

Traffic Classes

The protocol version of a traffic class is determined by the protocol version of the access control list (ACL) that was used to configure the traffic class. IPv6 traffic classes are supported using named IPv6 ACLs. Traffic classes are also supported on PPP sessions.

For configuration information, see the “Configuring ISG Subscriber Services” module in this guide.

  • Native IPv4/IPv6

  • PPP dual stack

  • Protocol dependent

Time-Based Billing Service

The Time-Based Billing feature calculates the 24-hour volume usage for all subscriber sessions that are active on an L2TP network server (LNS) at a specified time each day. It reports the volume used by a session since the last specified time, in 24-hour intervals. You can configure the router to collect the volume statistics of all active sessions at the same time every day, for example, everyday at midnight. The system would report the volume usage of a session from midnight of the previous day to midnight of the current day.

Time-based billing will also report input and output traffic statistics for IPv6 and IPv4 traffic separately and as an aggregate using new AAA attributes in AAA accounting records.

Changes in local time based on Day Light Savings Time (DST), Network Time Protocol (NTP), or clock changes configured on the router are taken into account when reporting volume statistics at the specified time.

Time-based billing is supported for IPv4, IPv6, and PPP sessions.

How to Configure ISG IPv6 Support

For information on creating IPv6 subscriber sessions for routed ISG subscribers, see the module “Configuring ISG Access for IP Subscriber Sessions.”

Note

IPv6 sessions for Layer 2 connected subscribers are not supported.

Defining an IPv6 Prefix for ISG Subscriber Sessions

To enable ISG to create an IPv6 subscriber session after receiving the first packet with a particular IPv6 prefix, you define the IPv6 prefix in an IP subscriber list.

SUMMARY STEPS

  1. enable
  2. configure terminal
  3. ip subscriber list list-name
  4. ipv6 prefix default length
  5. exit
  6. interface type number
  7. ip subscriber routed
  8. initiator unclassified ip-address [ipv6 ] [list list-name]
  9. end

DETAILED STEPS

  Command or Action Purpose
Step 1

enable

Example:

Router> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.

Step 2

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3

ip subscriber list list-name

Example:

Router(config)# ip subscriber list mylist

Specifies the IP subscriber list name and enters server list configuration mode.

Step 4

ipv6 prefix default length

Example:

Router(config-server-list)# ipv6 prefix default 64

Defines the IPv6 prefix for which ISG initiates IPv6 subscriber sessions.

Step 5

exit

Example:

Router(config-server-list)# exit

Returns to global configuration mode.

Step 6

interface type number

Example:

Router(config)# interface GigabitEthernet 2/0/0

Specifies an interface and enters interface configuration mode.

Step 7

ip subscriber routed

Example:

Router(config-if)# ip subscriber routed

Specifies that routed IP subscribers are to be hosted on the interface and enters ISG IP subscriber configuration mode.

Step 8

initiator unclassified ip-address [ipv6 ] [list list-name]

Example:

Router(config-subscriber)# initiator unclassified ip-address ipv6 list mylist

Enables ISG to create an IPv6 subscriber session after receiving a packet with the IPv6 prefix.

Step 9

end

Example:

Router(config-subscriber)# end

Returns to privileged EXEC mode.

Configuring Time-Based Billing Service

ISG time-based billing is configured in the service profile on a AAA server. If you include a traffic class in the service profile, time-based billing will apply to the specified flow. If you do not configure a traffic class, time-based billing will apply to the session.

Before you begin

ISG per-session or per-flow accounting must be configured.

SUMMARY STEPS

  1. Cisco-AVpair = “PPWhh :mm :ss :d ”
  2. Cisco-AVpair = “ip:traffic-class={in | out} access-group [acl-number | name acl-name ] [priority n ]”
  3. show subscriber session feature time-based-billing detailed

DETAILED STEPS

Step 1

Cisco-AVpair = “PPWhh :mm :ss :d ”

Add the Post Paid VSA to the service profile. This attribute specifies the weekly tariff-billing points as follows:

hh :mm :ss :d —Weekly billing time.

  • hh = hour of day <0–23>

  • mm = minutes <0–59>

  • ss = seconds <0–59>

  • d = bitmap format for the days of week. Each weekday is represented by one bit, as follows:
    • 00000001 = Monday
    • 00000010 = Tuesday
    • 00000100 = Wednesday
    • 00001000 = Thursday
    • 00010000 = Friday
    • 00100000 = Saturday
    • 01000000 = Sunday
Step 2

Cisco-AVpair = “ip:traffic-class={in | out} access-group [acl-number | name acl-name ] [priority n ]”

Add the ISG traffic class attribute to the service profile. This attribute specifies the input and output traffic to which the service will apply. Both an input and output traffic classifier can be added to a service profile.

Step 3

show subscriber session feature time-based-billing detailed

Enter this command on the ISG router to display information about time-based billing. The following example shows output from this command: 


Router# show subscriber session feature time-based-billing detailed

--------------------------------------------------
Type: IP, UID: 7, State: authen, Identity: aabb.cc00.6400
Session Up-time: 00:00:08, Last Changed: 00:00:08
Switch-ID: 4102

Time-based-billing:
Class-id   Dir  Last-Tariff  Packets-v4    Bytes-v4    Packets-v6	Bytes-v6  Source
0          In   1291415061   4             400         2          200       Peruser
1          Out  1291415061   3 			         200		       1 			      100	      Peruser

Configuration Examples for ISG IPv6 Support

Example: IPv6 Prefix for ISG Subscriber Sessions

The following example shows an IPv6 prefix defined in the IP subscriber list named mylist, which has been assigned to Gigabit Ethernet port 0/0/0. ISG will create an IPv6 subscriber session when it receives the first packet with the default IPv6 prefix. 

ip subscriber list mylist
  ipv6 prefix default 64

interface GigabitEthernet0/0/0
 ip vrf forwarding vrf-1
 ip address 10.1.1.1 255.255.255.0
 ip access-group 101 out
 ip virtual-reassembly
 zone-member security private
 media-type sfp
 negotiation auto
 ipv6 address 2001:DB8:1:1::26/64
 ip subscriber routed
  initiator unclassified ip-address ipv6 list mylist

Example: Time-Based Billing Service

The following example shows an IPv6 session configured for doing billing daily at midnight: 

PPW00:00:00:127

Day 1—A native IPv6 session starts at 10 a.m.

Day 1 at tariff-switch point (12 a.m.)—A snapshot of the current volume used from 10 a.m. is recorded, for example: 

IPv6-input-bytes = 10000  
IPv6-input-packets = 100 
IPv6-output-bytes = 20000 
IPv6-output-packets= 200

Day 2 say at 12:10 a.m.—Interim record is sent. The Interim record will carry the following values in the VSAs: 


Tariff-Input-Packets = 100          Aggregate Input IPv4 and IPv6 Packets
Tariff-Input-Octets = 10000         Aggregate Input IPv4 and IPv6 Bytes
Tariff-Input-Packets-IPv6 = 100
Tariff-Input-Octets-IPv6 = 10000
Tariff-Output-Packets = 200         Aggregate Output IPv4 and IPv6 Packets
Tariff-Output-Octets = 20000        Aggregate Output IPv4 and IPv6 Bytes
Tariff-Output-Packets-IPv6 = 200
Tariff-Output-Octets-IPv6 = 200

Day 2—All Interim records sent thereafter until the next tariff-switch point will carry the above values.

Day 2 at tariff-switch point (12 a.m.)—A snapshot of the volume used from Day 1 at 12 a.m. to Day 2 at 12 a.m. is recorded, for example: 

IPv6-input-bytes = 600000  
IPv6-input-packets = 6000 
IPv6-output-bytes = 20000  
IPv6-output-packets= 200

Day 3 say at 12:20 a.m.—Interim record is sent. The Interim record will carry the following values in the VSAs: 


Tariff-Input-Packets = 6000         Aggregate Input IPv4 and IPv6 Packets
Tariff-Input-Octets = 600000        Aggregate Input IPv4 and IPv6 Bytes
Tariff-Input-Packets-IPv6 = 6000
Tariff-Input-Octets-IPv6 = 600000
Tariff-Output-Packets = 200         Aggregate Output IPv4 and IPv6 Packets
Tariff-Output-Octets = 20000        Aggregate Output IPv4 and IPv6 Bytes
Tariff-Output-Packets-IPv6 = 200
Tariff-Output-Octets-IPv6 = 200

Day 3—All Interim records sent thereafter until the next tariff-switch point will carry the above same values.

Day 4—The session is disconnected at 8 a.m. A snapshot of the volume used from last tariff to the session disconnect time is taken, for example: 

IPv6-input-bytes = 500  
IPv6-input-packets = 1 
IPv6-output-bytes = 400  
IPv6-output-packets= 1

A stop record is sent with the following values in the VSAs: 


Tariff-Input-Packets = 1            Aggregate Input IPv4 and IPv6 Packets
Tariff-Input-Octets = 500           Aggregate Input IPv4 and IPv6 Bytes
Tariff-Input-Packets-IPv6 = 1
Tariff-Input-Octets-IPv6 = 500
Tariff-Output-Packets = 1           Aggregate Output IPv4 and IPv6 Packets
Tariff-Output-Octets = 400          Aggregate Output IPv4 and IPv6 Bytes
Tariff-Output-Packets-IPv6 = 1
Tariff-Output-Octets-IPv6 = 400

The following example shows an IPv4 session configured for doing billing daily at midnight: 

PPW00:00:00:127

Day 1—A native IPv4 session starts at 10 a.m.

Day 1 at tariff-switch point (12 a.m.)—A snapshot of the current volume used from 10 a.m. is recorded, for example: 

IPv4-input-bytes = 10000  
IPv4-input-packets = 100 
IPv4-output-bytes = 20000  
IPv4-output-packets= 200

Day 2 say at 12:10 a.m.—Interim record is sent. The Interim record will carry the following values in the VSAs: 


Tariff-Input-Packets = 100          Aggregate Input IPv4 and IPv6 Packets
Tariff-Input-Octets = 10000         Aggregate Input IPv4 and IPv6 Bytes
Tariff-Output-Packets = 200         Aggregate Output IPv4 and IPv6 Packets
Tariff-Output-Octets = 20000        Aggregate Output IPv4 and IPv6 Bytes

Day 2—All Interim records sent thereafter until the next tariff-switch point will carry the same above values.

Day 2 at tariff-switch point (12 a.m.)—A snapshot of the volume used from Day 1 at 12 a.m. to Day 2 at 12 a.m. is recorded, for example: 

IPv4-input-bytes = 600000  
IPv4-input-packets = 6000 
IPv4-output-bytes = 20000  
IPv4-output-packets= 200

Day 3 say at 12:20 a.m.—Interim record is sent. The Interim record will carry the following values in the VSAs: 


Tariff-Input-Packets = 6000         Aggregate Input IPv4 and IPv6 Packets
Tariff-Input-Octets = 600000        Aggregate Input IPv4 and IPv6 Bytes
Tariff-Output-Packets = 200         Aggregate Output IPv4 and IPv6 Packets
Tariff-Output-Octets = 20000        Aggregate Output IPv4 and IPv6 Bytes

Day 3—All Interim records sent thereafter until the next tariff-switch point will carry the same above values.

Day 4—The session is disconnected at 8 a.m. A snapshot of the volume used from the last tariff-switch point to session disconnect time is taken, for example: 

IPv4-input-bytes = 500  
IPv4-input-packets = 1 
IPv4-output-bytes = 400  
IPv4-output-packets= 1

A stop record is sent with the following values in the VSAs: 


Tariff-Input-Packets = 1            Aggregate Input IPv4 and IPv6 Packets
Tariff-Input-Octets = 500           Aggregate Input IPv4 and IPv6 Bytes
Tariff-Output-Packets = 1           Aggregate Output IPv4 and IPv6 Packets
Tariff-Output-Octets = 400          Aggregate Output IPv4 and IPv6 Bytes

Additional References

Related Documents

Related Topic

Document Title

Cisco IOS commands

Cisco IOS Master Commands List, All Releases

ISG commands

Cisco IOS Intelligent Services Gateway Command Reference

IPv6 Configuration

IPv6 Configuration Guide, Cisco IOS XE Release 3S

Configuring ISG accounting

“Configuring ISG Accounting” module in this guide

Configuring ISG timers

“Configuring ISG Policies for Session Maintenance” module in this guide

Configuring Layer 4 redirect

“Redirecting Subscriber Traffic Using ISG Layer 4 Redirect” module in this guide

Configuring traffic classes

“Configuring ISG Subscriber Services” module in this guide

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http://www.cisco.com/cisco/web/support/index.html

Feature Information for ISG IPv6 Support

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 1. Feature Information for ISG IPv6 Support

Feature Name

Releases

Feature Information

ISG IPv6 Support

Cisco IOS XE Release 3.4S

Adds IPv6 support for routed IP subscriber sessions and for the following ISG features:

  • Absolute Timeout

  • Idle Timeout

  • ISG Accounting

  • Traffic Classes

Adds the Time-Based Billing feature and traffic class support for services and flows on PPP sessions.
Note 

Only single-stack sessions are supported for ISG subscriber sessions; dual-stack sessions are not supported.

The following commands were introduced or modified: initiator , ipv6 prefix , show ip subscriber , show subscriber session .

ISG: IPv6 Support phase II

Cisco IOS XE Release 3.5S

Adds support for IPv6 PPP sessions and PPP dual-stack sessions for the following features:

  • HA-supported ISG features

  • ISG Policer

  • Layer 4 Redirect

  • MQC

Adds support for PPP dual-stack sessions for the following features:

  • Absolute Timeout

  • Idle Timeout

  • ISG Accounting

  • Traffic Classes

The following commands were introduced or modified: redirect session-limit , redirect to , show redirect group , show redirect translations , server ip .