Connection termination points for services and interfaces

Overview

Connection termination points are objects that represent terminating endpoints for a service, for example the endpoint of a VLL service. Connection termination points can be Layer 2 or Layer 3 interfaces, depending on the type of service being created. At the connection termination points you must configure the mode as Access or Network, the Encap Type as required, the MTU size as required, and the configured MAC address as required when configuring the port or channel. The following objects can be used for connection termination points:

STS-3 to STS-192 clear channel

STS-3 to STS-192 clear channel SONET/SDH ports can be used to create SAPs or IP interfaces with one clear channel on each port that operates at the rate of the parent object. Clear channel SONET applications can be performed on any OC-n card. SONET channel termination for 1 × 10-Gig MDAs are not supported. See  SONET clear channel applications in this section for more information.

DS3 clear channel

A DS3 clear channel can be a connection termination point when it is explicitly configured as unchannelized, that is, when the Configuration Type is set to None, which is the default setting for a DS3. DS3 clear channel connections cannot be channelized to a lower level than the one full DS3 channel. See TDM channelization and clear channel applications in this section for more information.

DS0 channel groups

A TDM channel group connects a group of DS0s by allocating a specific number of spans or interfaces and channels to a group of channels. The DS0 channel group defines the incoming and outgoing parameters for a group of channels such as IP profiles, routing tables, and translation tables to be assigned during the configuration of the specific channel group.

To use a DS1 or E1, you must create at least one DS0 group for the DS1 or E1. The NFM-P supports the automatic configuration of sub-channels and assignment of timeslots on the ports within DS0 groups. Depending on the TDM port selected, the NFM-P automatically creates the DS0 channel groups with the appropriate type of timeslots. For example, you can assign timeslots to a DS0 channel group as follows:

You can view the channels that are assigned in DS0 groups using the associate properties form. You can also disable, enable, or reassign the assignment of timeslots as required, in a DS0 group.

See TDM channelization and clear channel applications in this section for more information about DS0 channel groups. See To perform a bulk channel creation on ports that support multiple sub-channels for information about creating channels on ports for card types that support multiple sub-channels. See To configure TDM DS1 or E1 channels for information about creating TDM DS1 or E1 channels and DS0 channel groups.

SONET STS-1 sub-channels

Only the DS0 group level can be used as a connection termination point for SONET STS-1 sub-channels. Channelization on the 1 × OC12 can be used to create up to 12 SONET STS-1 sub-channels. Each STS-1 channel can be used to create a DS3 frame on which you can build DS1 or E1 channels that can be configured to the DS0 channel group level. You can configure the DS0s of a DS0 group in any sequence and you do not need to use all DSOs. For example, you can use DS0 1, 3, 5, and 9. See SONET VT1.5 and VT2 payloads in this section for more information.

Only the DS0 group level can be used as an endpoint on the channelized 12 × DS3 card. Channelization can be used on each DS3 port of the card to create independent TDM channels in the form of DS1 or E1 data channels that handle DS0 groups. The DS0s of a DS0 group can be configured in any sequence and you do not need to use all DS0s. For example, you can use DS0 1, 3, 5, and 9. See SONET and SDH sub-channel applications and structure in this section for more information.

Ethernet ports

Ethernet ports can be configured as connection termination points in SAPs and IP interfaces. They cannot be channelized.

You must configure the class of port, such as fast Ethernet, GigE, or 10G Ethernet. You must also configure the port encapsulation at the connection termination point. Ethernet access ports use:

You must configure the duplex parameter from the Ethernet tab if the port is to be added to a LAG. Configure the Dot1 Q Ethertype and Q in Q Ethertype parameters from the Ethernet tab, if required. The range is 1536 to 65 535.

You must also configure the speed parameter from the General tab. The options are 10, 100, 1000, or 10 000, depending on the speed of the Ethernet interface.

Most OmniSwitch chassis offer four hybrid or combo ports. These ports consist of four paired 10/100/1000Base-T ports and four 1000 SFP ports. Preferences for these ports are configurable and, depending on the configuration, redundancy can be provided if a link fails.

PXC loopback ports

You can place a port in an internal loopback mode called a port cross-connect (PXC). Each PXC is associated with a single physical port, and contains two logical PXC sub-ports. One PXC sub-port is created per upstream or downstream path. PXC ports can be added to hybrid LAGs, and associated with the following interfaces:

Supported breakout ports can be associated to a PXC. The PXC ports can be added to either a LAG or FPE. The LAG with the PXC can be associated to the FPE. See To create an FPE for information about configuring FPE.

PXC ports are configured in the Equipment tree. See To configure PXC loopback ports for information about configuring a PXC port.

Xconnect anchor ports

The PXC functionality uses the loopback mechanism of anchor ports to feed traffic from egress forwarding context into the ingress forwarding context on the same line card utilizing the E-chip functionality.

The Xconnect object appears automatically in the navigation tree under daughter cards supported NEs. After you create MAC on the Xconnect, you can create up to 2 loopbacks. Each loopback creates respective anchor ports in the navigation tree (Port 1/1/m1/1). The anchor ports can be associated to a PXC.

See To create and configure Xconnect anchor ports for information about configuring anchor ports.

OmniSwitch learned port security

LPS provides a mechanism to control network device access on one or more OmniSwitch ports. Configurable LPS parameters allow you to restrict the source learning of host MAC addresses to:

The following options allow you to specify how the LPS port handles unauthorized traffic.

See To configure bridging on an OmniSwitch for information about enabling LPS on Ethernet ports and configuring LPS properties. See To configure OmniSwitch Ethernet ports for information about configuring static MAC addresses on LPS enabled Ethernet ports.

Note: A deployment error is displayed in NFM-P while creating a LAG with ports. This deployment failure occurs if there is an LPS/VLAN configuration done on a specific port, using CLI.

MTU size and port configuration

You must specify the MTU size for an Ethernet port using the MTU (bytes) parameter on the General tab at the connection termination endpoint.

Consider the following when you configure MTU parameters.

See the device specific documentation for end-to-end considerations for configuring maximum MTU size throughout the managed network.

The Ethernet port MTU parameter indirectly defines the largest physical packet that the port can transmit or that the far-end Ethernet port can receive. Packets received that are larger than the MTU are discarded. Packets that cannot be fragmented at egress and that exceed the MTU are discarded.

The parameters for MTU configuration include the destination MAC address, source MAC address, Ethernet encapsulation type, length field, and complete Ethernet payload.

The MTU value for a port is associated with the port mode, such as access or network, and the port encapsulation type. If you change the mode or encapsulation type value for a port, the NFM-P adjusts the MTU value to a default value. If you do not want the MTU values for ports to revert to the defaults, you can configure the NFM-P to retain the currently configured MTU values for ports regardless of a mode or encapsulation type change. See To configure the NFM-P to retain non-default port MTU values for more information.

HSMDA Egress Secondary Shapers

The egress port scheduler combines all subscriber queues of the same scheduling class and services the queues in a byte fair round robin fashion. This results in more packets being forwarded into the aggregation network towards a DSLAM than the DSLAM can accept. If the HSMDA egress port is congested, the egress bandwidth represented by the downstream discarded packets to the DSLAM may be allocated packets destined to other DSLAMs.

The HSMDA supports egress secondary shapers to provide a control mechanism to prevent downstream overruns without affecting the class-based scheduling behavior on the port. All subscribers destined to the same DSLAM have their queue groups mapped to the same egress secondary shaper. As the scheduler services the queues within the groups according to scheduler class, the destination shaper is updated.

After the shapers rate threshold is exceeded, scheduling for all queues associated with the shaper is stopped. When the dynamic rate drops below the threshold, the queues are allowed to be placed back on the scheduler service lists. By removing the queues from their scheduling context for a downstream congested DSLAM, the port scheduler is allowed to fill the egress port with packets destined to other DSLAMs without affecting class behavior on the port.

Egress secondary shapers are configured per port.

PoE

PoE provides power directly from the Ethernet ports. Powered devices such as IP phones, wireless LAN stations, Ethernet hubs, and other access points can be plugged directly into PoE-enabled Ethernet ports. The NFM-P supports PoE and PoE+ on supporting devices. See the following procedures: