The UEM manages all the major components of the USP architecture. Conforming to ETSI MANO, the UEM is modeled as the element management system (EMS) for the USP which is a complex VNF comprised of multiple VNFCs. The UEM and the complex VNF are represented to the Management and Orchestration (MANO) infrastructure through their own VNF descriptors (VNFDs).

Although comprised of multiple modules, the UEM provides a single northbound interface (NBI) to external elements such as the OSS/BSS and Ultra Web Service (UWS).

The UEM provides the following network management functions:

• Configuration

• Fault management

• Usage accounting

• Performance measurement

• Security management

• Operational state of VNF

The northbound interface exposes all the information collected, aggregated and exposed through an API interface.

• All the interactions with entities northbound of the UEM happen via a single programmable API interface (e.g. REST, NETCONF, SNMP, etc.) for the purpose of collecting:

  • Configuration data for platform services and for Day-N configuration of its various components

  • Operational data pertaining to the system such as topology (VDU creation and organization) and different levels of VDU and service liveliness and KPIs based on the topology

  • Event streams (NETCONF notifications) that are used by the UEM to asynchronously notify northbound entities

  • Remote Procedure Calls (RPCs) used to expose some of the functionalities offered by the platform or its components such as packet tracing or mirroring

  • Asynchronous notifications: When an event that is relevant to northbound, is received from southbound, the SCM relays the event via a Netconf notification

These functions are provided via several different modules that comprise the UEM:

• Lifecycle Manager (LCM): The LCM exposes a single and common interface to the VNFM (Ve-Vnfm) that is used for performing life-cycle management procedures on a VNF. As a component within the UEM, it supports the various middleware application programming interfaces (APIs) required to interact with VNF and its components. Refer to Life Cycle Manager for more information.

• Service Configuration Manager (SCM): Leverages a YANG-based information model for configuration to provide configuration information to the VNFC Control Function (CF) VMs and other third-party components. It performs this functionality via NETCONF interfaces using pre-configured templates/network element drivers (NEDs). Configuration information is stored in the configuration database (CDB) and passed to the CF VM over the configuration interface via ConfD. Refer to Service Configuration Manager for more information.

• Service Level Agreement Manager (SLA-M): Provides timely access to information such as key performance indicators (KPIs), serviceability events, and diagnostic and troubleshooting information pertaining to components within the USP VNF instance such as:

  • The Lifecycle Manager

  • The Control Function (CF)

  • VMs that are part of the VNFCs

  • Any 3rd party applications related to USF service chains (depending on the VNFC)

  The SLA-M passes the information it collects over the northbound interface of the UEM. Refer to Service Level Agreement Manager for more information.

  Based on the StarOS, the CF is a central sub-system of the VNF that interacts with other sub-systems like service functions (SFs), network functions (NFs), and Application Functions (AFs) using field-tested software tasks that provide robust operation, scalability, and availability. It is equipped with a corresponding CDB for storing configuration information provided by the SCM via ConfD and/or CLI over the management interface. Refer to Control Function for more information.

High-availability (HA) is ensured across all of these components by the UEM-HA framework via a light-weight protocol that monitors the CF and SLA-M over the High-availability interface. All components are deployed redundantly. In the event of an issue, functions will be switched-over to the standby host. The SLA-M also uses the NETCONF interface to pull KPIs and event/log information from the CF.

The Control Function (CF) is a StarOS based central sub-system of the VNF. It interacts with other sub-systems such as service functions (SFs), network functions (NFs), and Application Functions (AFs), and uses field-tested software tasks that provide robust operation, scalability, and availability. The VNFD and VNFR are equipped with a corresponding configuration database (CDB) for storing configuration information provided by the SCM via ConfD and/or CLI NEDs over the management interface.

The CF also communicates over the High-availability (HA) interface for communicating with the LCM and to provide KPIs and event logs to the SLA-M.

Two CF VMs act as an active:standby (1:1) redundant pair. Within the StarOS, each CF VM is viewed as a virtual card and is responsible for the following functions:

• Hosting Controller tasks

• Hosting the Local context VPNMGR

• Hosting Local context (MGMT) and DI-Network vNICs

• Managing System boot image and configuration storage on vHDD

• Facilitating record storage on vHDD

• Providing Out-of-Band (OOB) management (vSerial and vKVM) for CLI and logging

• Working with the LCM to:

  • Bring VDUs online or offline during system initialization, request more VDUs for scale-out, return VDUs for scale-in lifecycle operations using VPD

  • Facilitate VDU internal management and configuration using predefined artifacts

• Providing KPI, event, and log information to the SLA-M as requested/needed

  Note	Refer to the Life Cycle Manager section for more information.

Important

The Intel Data Plane Development Kit (DPDK) Internal Forwarder task (IFTASK) is used to enhance USP system performance. It is required for system operation. Upon CF instantiation, DPDK allocates a certain proportion of the CPU cores to IFTASK depending on the total number of CPU cores.

Service Function (SF) VMs provide service context (user I/O ports) and handle protocol signaling and session processing tasks. A UGP instance can have a maximum of 14 SF VMs, of which a maximum of 12 SF VMs can be active. .

Each SF VM dynamically takes on one of three roles as directed by the CF:

• Demux VM (flow assignments)

• Session VM (traffic handling)

• Standby VM (n+1 redundancy)

An SF provides the following functions:

The minimum configuration for an Ultra Gateway Platform instance requires four SFs: two active, one demux, and one standby.

Note	The Intel Data Plane Development Kit (DPDK) Internal Forwarder task (IFTASK) is used to enhance USP system performance. It is required for system operation. Upon CF instantiation, DPDK allocates a certain proportion of the CPU cores to IFTASK depending on the total number of CPU cores.

When deployed in support of the Ultra Services Framework (USF), the SF facilitates the StarOS software tasks pertaining to the IP Services Gateway (IPSG) traffic detection function (TDF). The IPSG receives subscriber policy information from the Policy and Charging Rules Function (PCRF) over the Gx/Gx+ interface. It uses this policy information to steer subscriber session traffic received over the Gi/SGi interface through the SFC as required.

The Network Function (NF) is a virtual machine that is dedicated as a networking adapter between a DI system and external routers. The NF can be used to aggregate the VNF external connection points to a consolidated set of external interfaces. NF virtual machines are typically used for larger DI systems to limit the number of external interfaces to those present on a smaller set of virtual machines. The NF facilitates the building of large scale, high performance systems by providing the virtual equivalent of specialized Network Processing Unit (NPU) hardware.

The NF provides the following functions:

• Serves as a dedicated system for performing high speed traffic classification and flow/counter aggregation based on policies (n-tuple; each NF has access to complete set of policies)

• Limits the number of external interfaces required by aggregating external connection points to a consolidated set of high speed interfaces

• Operates as networking adapter between USP VNFs and external routers

• Subscriber awareness and stickiness as part of flow classification.

• Traffic classification and load balancing

The NF deploys a FAST-PATH architecture leveraging the NPU Manager and NPU SIM software tasks to ensure performance and scalability.

The mobility/DPDK internal forwarder (IF) is the core functional block for the USP architecture. It runs NPUSIM with DPDK into NF. The main functions of the mobility forwarder are:

• Performing the flow classification for each incoming packet, based on pre-configured rules.

• Deriving the service chain that needs to be associated with a flow

• Maintaining the subscriber stickiness - Meaning all the flows of a subscriber should land on the same service path (service path maps to AF).

• Performing the NSH encapsulation/ decapsulation. It uses NSH for communicating the service chain information across the nodes.

The Application Function (AF) is a virtual machine that is dedicated for Ultra Service Framework within a Gi-LAN Service Function Chain. The CF manages the system initialization, resource management, and high availability of the AF virtual machines. Packets that will be routed through a service function are encapsulated by the NF using NSH chain and routed to the AF. The AF learns of the specific service chain from the NSH header and routes the un-encapsulated packets through the Ultra Service Components (USCs) that comprise the chain. Once the packets are serviced, they are re-encapsulated and routed back to the NF.

The AF VM maps the service chain identifier to a local tag representing the link/path between the NF and service component. The service path consists of a single service function, chain of different service functions, or service path spawned over multiple hosts. Like the NF, the AF deploys a FAST-PATH architecture leveraging the network processing unit (NPU) Manager and NPU SIM software tasks to ensure performance and scalability.

The USP supports different types of VNFs that provide a variety of mobility services. Each VNF consists of components (VNFCs) which run on different virtual machines (VMs). The following VNF types are supported in this release:

• Ultra Gateway Platform (UGP): The UGP currently provides virtualized instances of the various 3G and 4G mobile packet core (MPC) gateways that enable mobile operators to offer enhanced mobile data services to their subscribers. The UGP addresses the scaling and redundancy limitations of VPC-SI (Single Instance) by extending the StarOS boundaries beyond a single VM. UGP allows multiple VMs to act as a single StarOS instance with shared interfaces, shared service addresses, load balancing, redundancy, and a single point of management.

• Ultra Policy Platform (UPP): Delivers next generation policy and subscriber management functionality by leveraging the Cisco Policy Suite (CPS). CPS is carrier-grade policy, charging, and subscriber data management solution. It helps service providers rapidly create and bring services to market, deliver a positive user experience, and optimize network resources.

  Note	The UPP is not supported in this release.

• Ultra Service Framework (USF): The USF enables enhanced processing through traffic steering capabilities for subscriber inline services. USF Gi-LAN Service Function Chains (SFC) classify and steer traffic enabling mobile operators to quickly deploy new services and applications to their subscribers.

AutoIT is the UAS software role used to automate the process of:

• Deploying the VIM Orchestrator (synonymous with the OpenStack Undercloud).

• Installing the virtual infrastructure manager (VIM, synonymous with the OpenStack Overcloud) which manages the network function virtualization infrastructure (NFVI).

• Onboarding/upgrading the USP ISO software package onto the Ultra M Manager Node.

AutoIT performs the deployments based on manifests it receives from AutoDeploy. Additionally, also hosts a webserver to facilitate VM deployment and delivery of software packages using REST and ConfD APIs for provisioning Overcloud nodes.

AutoIT can be deployed in the following scenarios:

• As a single VM on the Ultra M Manager Node (the same physical server as AutoDeploy and OSP-D VM) during a bare metal installation.

• In high-availability (HA) mode which provides 1:1 redundancy. When deployed in HA mode, two AutoIT VMs are deployed: one active, one standby.

• As a single VM within an existing OpenStack deployment.

• In HA mode within an existing OpenStack deployment.

When supporting VIM installation automation processes, AutoIT:

• Sets up AutoIT nodes

• API endpoint based on ConfD to Auto-Deploy and NSO

• Deploys the VIM Orchestrator

• Works through the VIM Orchestrator to deploy the VIM

• Brings up OSP-D as a VM

When supporting VNF deployment automation processes, AutoIT:

• Onboarding Ultra Automation Services (UAS) VMs.

• VIM provisioning to onboard VNFs.

• Manages different version of software packages by hosting into YUM repo.

• APIs to onboard VNF packages.

• Brings up AutoVNF VMs and monitors for failures.

• Stores release public key information in the ISO database for RPM signature verification by YUM through the installation process.

Important

In this release, AutoIT is only supported for use with Ultra M solutions based on the Hyper-Converged architecture.

In addition to supporting deployment workflows, AutoIT provides a centralized monitor and management function within the Ultra M solution. This function provides a central aggregation point for events (faults and alarms) and a proxy point for syslogs generated by the different components within the solution.

AutoDeploy is the UAS software role that provides single- and multi-Site AutoVNF orchestration. In this context, a “Site” is a single VIM instance. As such, a single AutoDeploy instance is capable of deploying the AutoVNF UAS software roles within multiple deployment scenarios:

• Single VIM/Single VNF

• Single VIM/Multi-VNF

Important

In this release, multi-VNF deployments are supported only in the context of the Ultra M solution. Refer to the Ultra M Solutions Guide for details.

In a multi-VNF environment, AutoDeploy can deploy up to four VNFs concurrently. Additional details pertaining to the deployment automation process are provided in the deployment automation documentation.

AutoDeploy can be deployed in the following scenarios:

• As part of VIM installation automation process:

  • On bare-metal with high availability (HA) support. HA support provides 1:1 VM redundancy. When deployed in HA mode, two AutoDeploy VMs are deployed on the same physical server: one active, one standby.

  • On bare-metal without HA support. In this scenario, a single AutoDeploy VM is deployed.

• As part of an existing deployment:

  • In HA mode within an existing OpenStack deployment. When deployed in HA mode, two AutoDeploy VMs are deployed on the same physical server: one active, one standby.

  • As a single VM within an existing OpenStack deployment.

In this release, one AutoDeploy VM is deployed per VIM. The AutoDeploy VM must have network access to the VIM in order to provide orchestration.

Once instantiated, AutoDeploy provides the following functionality:

• AutoVNFs bootstrapping and provisioning for deployments (Day-0/Day-1/Day-N).

• AutoVNF Deployments Life-Cycle including start, stop and Inventory management (consolidated).

• Performs release image signing validation by verifying the certificate and public key provided in the release ISO.

AutoDeploy operations are performed using any of the following methods:

• ConfD CLI and API based transactions

• WebUI based transactions

AutoVNF is the software role within UAS that provides deployment orchestration for USP-based VNFs. It does this by emulating an NFVO and VNFM for deployments.

When used in Ultra M solutuon deployments, AutoVNF is instantiated by the AutoDeploy software role based on configuration data you provide. It is deployed with a 1:1 HA redundancy model. Processes across the VMs are monitored and restarted if necessary. ConfD synchronizes the CDB between the active and standby VMs. Each of the VMs are deployed on separate Compute nodes within your VIM.

For VNF deployments brought up using only AutoVNF (e.g. Stand-alone AutoVNF-based deployments), only a single VM is deployed.

Once operational, AutoVNF provides the following functionality:

• Deploys the Elastic Services Controller (ESC), which serves as the VNFM, per configurable YANG-based definitions.

  Note	The Cisco Elastic Services Controller (ESC) is the only supported VNFM in this USP release.

• Onboards all required UEM VMs via the VNFM.

• Leverages configurable YANG-based definitions to generate the VNF descriptor (VNFD) required to onboard the VNF using UEM workflows.

• Determines all required resources for the VNF including images, flavors, networks, subnets and invokes NETCONF-based APIs to provision all of these resources into OpenStack through the VNFM.

• Ensures all references, network, images, and flavors exist on the VIM, if supplied.

• Monitors for NETCONF-based notifications, submits the transaction, and waits until the given transaction succeeds.

• Monitors inventory in terms of operational state and KPIs and auto-heals the VNFM and UEM.

• Orchestrates USP-based VNF upgrades regardless of whether or not Inter-Chassis Session Recovery (ICSR) is enabled on the VNF.

• Implements a ConfD-based architecture to provide life cycle management (LCM) through VNF-EM, VNFM, and VIM plugins as shown in Figure 2.

• Supports standard, ConfD-based REST/RESTCONF/NETCONF north-bound interfaces (NBIs).

• Provides VNF security, credentials, and SSH keys through the use of secure-tokens.

• Hosts an HTTP server to serve GET URLs supplied into the VNFD that include such things as configuration files, VDU images, etc.

• Supplies the VNFD to the UEM upon instantiation as Day-0 configuration using an appropriate VNFM-supported mechanism (e.g. in the case of ESC as the VNFM, the VNFD is passed as a Day-0 configuration using the ESC’s deployment APIs).

• Onboards all Day-0 configuration files onto the UEM to be passed on to VDUs.

• Allocates the management IP for the CF and UEM VMs along with Virtual IP (VIP) addresses.

AutoVNF operations can be performed using any of the following methods:

• ConfD CLI based transactions

• WebUI based transactions

• Netconf based transactions

The USP VNF relies on the underlying hardware and hypervisor for overall system redundancy and availability.

The hardware and hypervisor should provide:

• Redundant hardware components where practical (such as power supplies and storage drives)

• Redundant network paths (dual fabric/NICs, with automatic failover)

• Redundant network uplinks (switches, routers, etc.)

High availability can be achieved only if the underlying infrastructure (hosts, hypervisor, and network) can provide availability and reliability that exceeds expected values. The USP VNF is only as reliable as the environment on which it runs.

Inter-Chassis Session Recovery (ICSR) is also recommended to improve availability and recovery time in the case of a non-redundant hardware failure (such as CPU, memory, motherboard, hypervisor software). ICSR provides redundancy at the session level for gateways only. See ICSR Support for more information.

A minimum of three UEM VMs is required to support redundancy.

When three UEM VMs are used, they are deployed as part of an HA cluster which are 1:n redundant for overall management and inter-VNFM communications. The three VMs are deployed as follows: 1 leader or master (active), 1 follower or slave (standby), and 1 follower (standby).

In releases prior to 6.3, the default value was 3 and this parameter was not user configurable. In release 6.3 and beyond, the default value is 2.

By default, the UEM deploys two CF VMs which are 1:1 redundant for control of the USP VNF and the local context/management port. This is the recommended configuration.

The management port vNIC on both CFs are 1:1 redundant for each other and must be placed in the same VLAN in the infrastructure. Only one management port is active at a time.

Note	The two CF VMs must not run on the same physical host (server or blade) to achieve redundancy in case of the failure of the host or hypervisor.

SFs are deployed using 1:N redundancy. It is recommended that you have at least 2 active and 1 standby SF, however, the number of SF instances will change according to your deployment requirements.

Each SF VM provides network connectivity for service ports. Each SF provides one or more ports and associated interfaces, but the SFs do not provide 1:1 port redundancy as they are not paired together. Redundancy of SF ports should be achieved using ECMP or another supported L3 protocol.

The total throughput required of the USP VNF Instance should not exceed N-2 SFs with session recovery enabled so that any single SF can fail while the others take over its load. Use of loopback interfaces for service IP addresses is highly recommended.

Cisco recommends that you use Bidirectional Forwarding Detection (BFD) and Link Aggregation Group (LAG) for detection of path failures between an SF and the peer router so ECMP paths are excluded in the event of a failure.

1:1 session redundancy within a VNF and Inter-Chassis Session Recovery (ICSR) between VNFs is supported. Note that the session state is check-pointed at various call points within a call flow. Although session state is check-pointed in the UGP, the IP flow state and connection tracking tables are not mirrored. Therefore, any state associated with an IP flow will be lost.

When session recovery is enabled, one VM becomes the VPN/Demux and the remainder are session processing VMs. A standby SF can provide redundancy for any other SF.

Note	Each SF VM must run on a different physical host to achieve redundancy in case of the failure of the host or hypervisor.

NFs are deployed using 1:N redundancy. You may adjust the number of NF instances according to your deployment requirements.

Note	Each NF VM must run on a different physical host to achieve redundancy in case of the failure of the host or hypervisor.

AFs are deployed using 1:N redundancy. You may adjust the number of AF instances according to your deployment requirements.

Note	Each AF VM must run on a different physical host to achieve redundancy in case of the failure of the host or hypervisor.

The Ultra Services Components (USCs) used in the USF are deployed along with the AF into a MANO construct called an Element Group (EG). An EG is set of VDUs arranged for a unit of redundancy. As such, redundancy is available at the EGs-level and not for the individual USCs. An N:1 redundancy model is supported for Element groups.

USP VNFs support Inter-Chassis Session Recovery (ICSR) between two VNF instances for services that support Layer 3 ICSR in the StarOS software release. When more than one service type is in use, only those services that support ICSR will be able to use ICSR.

ICSR supports redundancy for Site/row/rack/host outages, and major software faults. To do so, the two USP VNF instances should be run on non-overlapping hosts and network interconnects. ICSR is supported only between like-configured UGP instances.

Note	ICSR between an USP VNF instance and another type of platform (such as an ASR 5500) is not supported.

For additional information, refer to the Inter-Chassis Session Recovery chapter in the System Administration Guide for your platform.