7. Internet Enhanced Service on the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C

This chapter provides information about Internet Enhanced Services support on the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C.

7.1. IES Service Overview

Internet Enhanced Service (IES) is a routed connectivity service where the subscriber communicates with an IP router interface to send and receive Internet traffic. An IES has one or more logical IP routing interfaces each with a SAP which acts as the access point to the subscriber's network.

IES allows IP interfaces to participate in the same routing instance used for service network core routing connectivity. IES services require that the IP addressing scheme used by the subscriber be unique between other provider addressing schemes and potentially the entire Internet. While IES is part of the routing domain, the usable IP address space may be limited. This allows a portion of the service provider address space to be reserved for service IP provisioning, and be administered by a separate, but subordinate address authority.

IP interfaces defined within the context of an IES service must have a SAP associated as the access point to the subscriber network. Multiple IES services are created to segregate subscriber owned IP interfaces.

Figure 79 shows a visual representation of IES.

Figure 79:  Internet Enhanced Service 

The IES service provides in-band management connectivity. Other features include:

  1. Multiple IES services are created to separate IP interfaces.
  2. More than one IES service can be created for a single customer ID.
  3. More than one IP interface can be created within a single IES service ID. All IP interfaces created within an IES service ID belong to the same customer.

7.2. IES Features

This section describes various general service features and any special capabilities or considerations as they relate to IES services.

7.2.1. IP Interfaces

IES customer IP interfaces can be configured with most of the options found on the core IP interfaces. The advanced configuration options supported are:

  1. ICMP Options
  2. VRRP — for IES services with more than one IP interface (available only in network mode)

In network mode, configuration options found on core IP interfaces not supported on IES IP interfaces are:

  1. NTP broadcast receipt

7.3. SAPs

7.3.1. IPv6 support for IES IP interfaces

IES IPv6 IP interfaces provide IPv6 connectivity in the routing base instance. It can be used to connect IPv6 networks over an IPv4 cloud using the IPv6 Provider Edge Router over MPLS (6PE) functionality. For more information about the 6PE, see the 7210 SAS-D, Dxp, K 2F1C2T, K 2F6C4T, K 3SFP+ 8C Router Configuration Guide, “IPv6 Provider Edge Router over MPLS (6PE)”.

IPv4 and IPv6 route table lookup entries are shared.

A separate route table (or a block in the route table) is used for IPv6 /128-bit prefix route lookup. A limited amount of IPv6 /128 prefixes route lookup entries is supported. The software enables lookups in this table by default (that is, no user configuration is required to enable Ipv6 /128-bit route lookup). A limited amount of IPv6 /128 prefixes route lookup entries is supported.

7.3.2. Encapsulations

The following SAP encapsulation is supported on IES services:

  1. Ethernet null
  2. Ethernet dot1q
  3. Ethernet QinQ
  4. Ethernet QinQ (access-uplink QinQ SAP)

7.3.3. CPE Connectivity Check

Static routes are used within many IES services. Unlike dynamic routing protocols, there is no way to change the state of routes based on availability information for the associated CPE. CPE connectivity check adds flexibility so that unavailable destinations will be removed from the service provider's routing tables dynamically and minimize wasted bandwidth.

The availability of the far-end static route is monitored through periodic polling. The polling period is configured. If the poll fails a specified number of sequential polls, the static route is marked as inactive.

An ICMP ping mechanism is used to test the connectivity. If the connectivity check fails and the static route is deactivated, the router will continue to send polls and re-activate any routes that are restored.

7.3.4. QoS Policies

When applied to 7210 SAS IES services, service ingress QoS policies only create the unicast queues defined in the policy. The multi-point queues are not created on the service. With IES services, service egress QoS policies function as with other services where the class-based queues are created as defined in the policy.

Note that MAC, IPv4, and IPv6 criteria can be used in the QoS policies for traffic classification in an IES.

7.3.4.1. CPU QoS for IES Access Interfaces in Network Mode

Traffic bound to CPU received on IES access interfaces are policed/rate-limited and queued into CPU queues. The software allocates a policer per IP application or a set of IP applications, for rate-limiting CPU bound IP traffic from all IES access SAPs. The policers CIR/PIR values are set to appropriate values based on feature scaling and these values are not user configurable. The software allocates a set of queues for CPU bound IP traffic from all IES access SAPs. The queues are either shared by a set of IP applications or in some cases allocated to an IP application. The queues are shaped to appropriate rate based on feature scaling. The shaper rate is not user-configurable.

Note:

  1. The instance of queues and policers used for traffic received on network port IP interfaces is different for traffic received from access port IP interfaces. Additionally the network CPU queues are accorded higher priority than the access CPU queues. This is done to provide better security and mitigate the risk of access traffic affecting the network side.
  2. IP DSCP marking of self-generated traffic is assigned by software on the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C.

7.3.5. Filter Policies

IP filter policies with IPv4 or IPv6 match entries can be applied to IES services.

7.3.6. VRRP Support for IES IP Interfaces in Network Mode

Virtual Router Redundancy Protocol (VRRP) for IPv4 is defined in IETF RFC 3768, Virtual Router Redundancy Protocol. VRRP describes a method of implementing a redundant IP interface shared between two or more routers on a common LAN segment, allowing a group of routers to function as one virtual router. When this IP interface is specified as a default gateway on hosts directly attached to this LAN, the routers sharing the IP interface prevent a single point of failure by limiting access to this gateway address. For more information about the use of VRRP, refer to the 7210 SAS-D, Dxp, K 2F1C2T, K 2F6C4T, K 3SFP+ 8C Router Configuration Guide.

VRRP is supported for IES IPv4 interfaces in network mode only. VRRP is not supported in access-uplink mode. It is also not supported for IPv6 interfaces in network or access-uplink mode.

Note:

Only one VRRP instance for each IP interface is supported on the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C.