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Service Attributes Overview

A service is defined by a set of attributes. Some attributes are common to all service instances created from one service definition, and are therefore set during service definition time. Other attributes are specific to a service instance and must be set in the service order. Some attributes can be set either in the service definition or in the service order; in such cases, it is up to the service designer to determine when the attribute will be set.

The Junos Space Ethernet Activator Space user interface groups service attributes as follows:

• General attributes—General information about the service, such as whether the service is point-to-point or multipoint, what signaling mechanism is used in the network core, and who the enterprise customer is who will use the service.
• UNI settings—Information about each customer site, including the N-PE device, interface, encapsulation (physical and logical), MTU, customer VLAN ID and range, service VLAN ID, bandwidth limiting, and so on.
• Connectivity settings—Information about connectivity among customer sites through the network. For point-to-point Ethernet services in a network with LDP switching in the network core, these settings will include the VC ID. For multipoint Ethernet (or VPLS) services these settings will include the route target and route distinguisher.

General Attributes

The following general attributes are defined for each service:

• Service Type
• Customer

Service Type

The service type attribute combines the topology and core signaling technology in the same attribute.

A service can have one of the following topologies:

• Point-to-point—The service uses a pseudowire to connect two customer sites across the network core.
• Multipoint—The service connects multiple customer sites in a virtual LAN across the network core.

The core signaling technology specifies the type of signaling used in the service provider’s network core. It can have one of the following values:

• LDP
• BGP

The service type is the first attribute to be determined during service definition. It can have one of the following values:

• Point-to-point Ethernet (LDP)—A virtual circuit between two customer sites using LDP signaling in the network core.
• Multipoint Ethernet—A Virtual private LAN service (VPLS) among multiple customer sites using BGP signaling in the network core.

Customer

This attribute specifies the enterprise customer who will use the service instance. This attribute is always specified in the service order.

UNI Settings

The following attributes are defined for the service endpoints or customer sites that are connected by the service:

• Ethernet Options
• N-PE Device
• Interface
• Protect Interface (Point-to-Point Services Only)
• MTU
• Traffic Type
• Customer VLAN ID
• Service VLAN ID and VLAN ID Range
• Physical Encapsulation
• Logical Encapsulation
• Rate Limiting and Bandwidth

Ethernet Options

This attribute identifies the interface type at the endpoint by defining the level packet tagging for the UNI. It can have the following values:

• port-port

  Transfers all data from the UNI to the other end of the LSP trunk.

• dot1q

  Tags each packet with a VLAN ID, thus allowing a specific VLAN to traverse the network.

• qinq

  Double tags each frame. The inner tag is added by the service provider. The service provider can use this inner tag to differentiate among services. For example, you can configure VLANs for a customer’s intranet with a different inner tag from VLANs used for working with providers or partners.

N-PE Device

Specifies the provider-edge device that connects the customer site to the network.

Interface

Specifies the physical interface on the N-PE device that connects the customer site or CE device to the N-PE device.

Protect Interface (Point-to-Point Services Only)

You can configure a protect interface for the logical interface linking a virtual circuit to its destination. The protect interface is a backup interface in case the primary interface fails. If the primary interface fails, traffic is switched to the protect interface. The protect interface is optional.

MTU

The MTU represents the largest frame size in bytes that passes through the UNI. MTU is configurable.

Note: This value is distinct from the MTU assigned to the connectivity in the network core.

Traffic Type

This attribute places restrictions on the traffic that can be transported across the network by the associated service. It can have the following values:

• Transport single VLAN

  Restricts the associated service to transporting just one VLAN across the network. This option can be used only with 802.1Q interface types.

• Transport VLAN range

  Allows the associated service to transport a range of VLANs across the network. This option can be used only with Q-in-Q interface types.

• Transport all traffic

  Allows the associated service to transport all traffic across the network. This option can be used with Q-in-Q interface types only.

  The traffic type attribute is not applicable to port-port services. Port-port services always transport all traffic.

Customer VLAN ID

Specifies a VLAN ID that is attached to each packet to permit VLANs to be shared across the network.

This attribute can be used only with 802.1Q and Q-in-Q interface types.

Service VLAN ID and VLAN ID Range

The service VLAN ID (SVLAN ID) specifies a second level of tagging to segregate groups of VLANs.

The VLAN range specifies a range of VLANs to be transported across the network by associating them with an SVLAN ID.

These options are configurable only for Q-in-Q interfaces.

Physical Encapsulation

Specifies the physical link-layer encapsulation type.

• flexible-ethernet-services—Offers the most flexibility, depending on the characteristics of the N-PE device and its line modules.

  For Gigabit Ethernet IQ interfaces and Gigabit Ethernet PICs with small form-factor pluggable transceivers (SFPs) only, use flexible Ethernet services encapsulation when you want to configure multiple per-unit Ethernet encapsulations. This encapsulation type allows you to configure any combination of route, TCC, CCC, and VPLS encapsulations on a single physical port. Aggregated Ethernet bundles cannot use this encapsulation type. If you configure flexible Ethernet services encapsulation on the physical interface, VLAN IDs from 1 through 511 are no longer reserved for normal VLANs.

  In the Junos Space Ethernet Activator product, you can use this encapsulation type with 802.1Q interfaces and Q-in-Q interfaces in point-to-point Ethernet services and in multipoint Ethernet services.

• vlan-ccc—You can use Ethernet VLAN encapsulation on CCC interfaces. This option restricts the range of available VLAN IDs to 512 through 4094. 1 through 511 are reserved for internal use.

  In the Junos Space Ethernet Activator product, you can use this encapsulation type with 802.1Q interfaces and Q-in-Q interfaces in point-to-point services.

• extended-vlan-ccc—Use extended VLAN encapsulation on CCC interfaces with Gigabit Ethernet interfaces that must accept packets carrying 802.1Q values.

  In the Junos Space Ethernet Activator product, you can use this encapsulation type with 802.1Q interfaces and Q-in-Q interfaces in point-to-point services.

• ethernet-vpls—Use Ethernet VPLS encapsulation on Ethernet interfaces that have VPLS enabled and that must accept packets carrying standard TPID values.

  In the Junos Space Ethernet Activator product, this encapsulation is used only for port-port interface types in multipoint Ethernet services.

Logical Encapsulation

Specifies the logical link-layer encapsulation type. Logical encapsulation allows 802.1Q and Q-in-Q services to route multiple services through the same physical interface.

• vlan-ccc—Use Ethernet virtual LAN (VLAN) encapsulation on CCC interfaces. When you use this encapsulation type, you can configure the family ccc only.
• extended-vlan-ccc—Use extended VLAN encapsulation on CCC interfaces with Gigabit Ethernet interfaces that must accept packets carrying 802.1Q values.
• vlan-vpls—Use VLAN VPLS encapsulation on Ethernet interfaces with VLAN tagging and VPLS enabled. Interfaces with VLAN VPLS encapsulation accept packets carrying standard Tag Protocol (TPID) values only.

Table 1 defines the logical encapsulation types that are valid for each physical encapsulation type in a point-to-point Ethernet service.

Table 2 defines the logical encapsulation types that are valid for each physical encapsulation type in multipoint Ethernet services:

Rate Limiting and Bandwidth

Rate limiting allows you to specify the maximum bandwidth permitted for a service.

The burst rate is automatically calculated as 2 times the MTU of the UNI.

Connectivity Settings

The following attributes are defined for the connectivity among UNI endpoints across the network:

• Virtual Circuit Identifier (VCID) (Point-to-Point Services Only)
• Route Targets and Route Distinguishers (Multipoint Services Only)
• Normalized VLAN (Multipoint Services Only)
• MTU

Virtual Circuit Identifier (VCID) (Point-to-Point Services Only)

This unique identifier can be assigned automatically from a pool of VCIDs or can be manually specified. It uniquely identifies a point-to-point virtual circuit through the network and is provided for all switched point-to-point services.

Route Targets and Route Distinguishers (Multipoint Services Only)

Route targets and route distinguishers are always automatically generated by the Junos Space software for multipoint Ethernet (VPLS) services. Route targets and route distinguishers designate the multipoint connectivity among the participating endpoints of a multipoint service. They identify the members of the virtual LAN.

Normalized VLAN (Multipoint Services Only)

Similar to point-to-point Ethernet services, the UNIs of VPLS services can be port-port, 802.1Q, or Q-in-Q. The type of VLAN mapping—or normalization—is specified in the service definition. VLAN normalization applies only to MX Series devices.

Normalization supports automatic mapping of VLANs. Normalization performs operations on VLAN tags to achieve the desired translation. The Ethernet Activator software supports two forms of VLAN normalization:

• Normalize all—The customer VLAN ID is preserved across the network. That is, the broadcast domain includes the interfaces that have the same VLAN ID across the VPLS service. For double-tagged packets (Q-in-Q interfaces), a “pop” operation at ingress strips the service VLAN ID from the packet. A corresponding “push” operation at egress inserts the service VLAN ID known at the local site. Hence, the service VLAN ID at egress does not have to match the service VLAN ID at ingress.

  For single-tagged packets (802.1Q interfaces), “Normalize All” has no effect, because the packet has no service VLAN ID to pop or push.

• Normalize none—The customer VLAN ID is not preserved across the network. The broadcast domain includes all VLANs at any site provisioned in the service. For single-tagged packets (802.1Q interfaces), a “pop” operation at ingress removes the customer VLAN ID from the packet. A corresponding “push” operation at egress adds a local customer VLAN ID.

  For double-tagged packets (Q-in-Q interfaces), both customer VLAN ID and service VLAN ID are popped from the packet at ingress and pushed at egress.

If normalization is not used, then all customer VLAN IDs and all service VLAN IDs must match to be part of the same broadcast domain.

Normalization works well with automatically assigned VLAN IDs, because the service provider does not need to specify the VLAN IDs that are popped and pushed. Without normalization, the service provider must specify explicitly the customer VLAN ID and the service VLAN ID.

MTU

MTU is the largest packet size that can traverse the LSP without fragmentation.

Note: This value is distinct from the MTU assigned on each UNI.