Avaya Cloud Office Unified Communications Reference Architecture
Table of Contents
1. Introduction
2. Acronyms
3. Reference Architecture Specification
4. SMB/SoHo Networks
5. Wireless Networks
6. Wide-Area Networks
7. CloudConnect
8. Software-Defined Networks and SD-WAN Networks
1. Introduction
This document provides Avaya Cloud Office customers with a reference architecture for the Unified Communication Services provided by Avaya Cloud Office. This document provides a description of the reference architecture and its functional components. These components reside in the Avaya Cloud Office Cloud, the network connecting the cloud with the enterprise sites, and at enterprise sites, and may be provided by Avaya Cloud Office, carriers, and customers.
The Avaya Cloud Office reference architecture can be used in conjunction with the Network Requirements and Recommendations to understand the context of the latter.
2. Acronyms
Table 1 summarizes the acronyms used in this document.
3. Reference Architecture Specification
The Avaya Cloud Office Unified Communications Reference Architecture is illustrated below. The top of the diagram indicates a call control function, a media server function, and carrier telephony interfaces. This functionality is implemented in the Avaya Cloud Office cloud. Details of this functionality are not provided because they are irrelevant for the enterprise-site requirements stated in this document. The figure provides representative sample designs of enterprise sites, including smaller site illustrating SoHo environments. In terms of traffic flow, the notions of inbound and outbound are defined relative to the local enterprise network that is connected to a service provider network:
• outbound is away from the enterprise site or in the direction of the service provider network.
• inbound is to the enterprise site or from the service provider network into the local enterprise network.
The functionality in the Reference Architecture is color-coded as follows:
• Avaya Cloud Office-provided cloud-based and onsite functionality including call controller, voice and video media servers, carrier interfaces, phones, and Avaya Cloud Office soft-clients running on enterprise computers, are illustrated in orange. Note that customers sometimes retain existing desk phones from prior non-Avaya Cloud Office VoIP deployments, in which case it is not designated as Avaya Cloud Office provided.
• Internet is green.
• Customer functionality is blue.
An enterprise network may include one or more of the following functional components:
• Firewall - Supports inbound and outbound packet filtering and network interfaces that can be of Ethernet, cable modem, or other types.
• Router - Performs IP routing and packet forwarding, and may support other functions such as layer 3 bandwidth management and ICMP related functions.
• Ethernet Switch - Supports frame switching and may support additional functions such as VLANs, layer 2 port control and filtering, and Power over Ethernet (PoE).
• Desktop Telephone - The phones perform two main functions:
• Call Control - Phone registration and call handling (setup, forwarding, teardown, call progress indication, etc.).
• Voice Signal Processing - Analog-to-digital and digital-to-analog conversion, sidetone injection, voice framing, jitter buffering, echo cancellation, speaker and microphone functionality.
• Endpoint - A device, such as a computer or mobile phone, running Avaya Cloud Office softphone or Glip may be connected to an Ethernet switch or WiFi network. In case a wired network is used, a computer may also be connected in series with a desk phone connected.
In general, enterprise network implementations are site dependent. For example, large offices will have more advanced firewalling, routing, and switching equipment than small branch-office sites. Implementation variations at enterprise sites include the following:
• One or multiple ISP WAN links may be present. In the latter case, one dedicated link could be used for VoIP service and another link for data services. Failover may be implemented between both links.
• Multiple firewalls may be present, for example, to demarcate a DMZ.
• The Wide Area Network interface, firewall, router, and switch may be implemented as separate functions or combinations of functions. In larger deployments, functions are often implemented as individual devices. In SMB environments, functions are often combined into fewer devices. An example is an all-in-one modem or cable modem, which combines the WAN interface, firewall, router, and switch functions. An all-in-one modem may also be configured to operate in bypass mode. In bypass mode, a separate firewall and router located behind the modem may be deployed to provide more advanced firewalling and routing capabilities.
• Multiple sites may be connected into a hub-and-spoke architecture, where all traffic between sites traverses the central hub. Traffic to/from the Internet may also have to pass the central hub. For redundancy purposes, the remote spokes may have a local Internet connection.
• Sites may be connected to the Avaya Cloud Office cloud by one or more private CloudConnect links, see (section 8).
• Several levels of routers or Ethernet switches may be present. This is typically the case at large enterprise site, which often have core switches connecting to access switches.
• Sites may have various types of desk phones and softphones, depending on user needs.
Voice and video calls can be made between phones at a single enterprise site, between phones at different enterprise sites, or calls may connect to an ITSP or a PSTN gateway. The Call Controller registers the phones and handles call orchestration between various components. To support calls, the following types of connectivity must exist from endpoints in the enterprise network:
• Call control connectivity with Avaya Cloud Office Call Controller
• Media path connectivity with Avaya Cloud Office Media Service
• Connectivity with various types of support services such as the Avaya Cloud Office provisioning service and a network time service.
4. SMB/SoHo Networks
Small Medium Businesses and Small Office - Home Office (SMB/SoHo) networks are mostly connected to cable provider or Digital Subscriber Line (DSL) ISP networks.
5. Wireless Networks
WiFi and 4G networks are pervasively used for enterprise communication since they provide flexible modes of cooperation between workers. WiFi devices include laptops, mobile phones, and hand-held devices.
6. Wide-Area Networks
Enterprises can use Wide-Area Networks (WANs) in various ways:
• Between sites within an enterprise as a private network.
• To connect an enterprise site or data center via a public or private connection to Avaya Cloud Office leveraging CloudConnect (Section 7).
7. CloudConnect
Avaya Cloud Office CloudConnect supports the ability to implement private connectivity between one or more enterprise sites and the Avaya Cloud Office Unified Communication Cloud. Depending on the type of CloudConnect, the enterprise/carrier Wide-Area Network (WAN) can be extended into one or both Avaya Cloud Office data centers in a cloud region. The network interface between the WAN and the Avaya Cloud Office cloud must meet Avaya Cloud Office’s physical and peering protocol requirements.
8. Software-Defined Networks and SD-WAN Networks
A Software-Defined Network (SDN) provides the ability to consistently manage connectivity and connection parameters, such as security and QoS, between sites leveraging centralized network control. Connections can be established between sites and services in a matter of minutes to hours, which used to take days or months. SDNs are an inlay network technology in the sense that they replace or optimize current network technologies to simplify end-to-end management of connections.
In contrast to SDN, Software-Defined Wide-Area Network (SD-WAN) is an overlay network technology build on top of already existing network infrastructures of one or more Internet Service Providers. It has similar characteristics as SDN by leveraging centralized control of connections. In addition, an SD-WAN allows dynamic steering of traffic over one or multiple service provider networks to establish the highest quality connection.
Both SDN and SD-WAN networks support delivery of Avaya Cloud Office Unified Communication services provided that the network requirements stated in this document are met. Avaya Cloud Office has a select group of SD-WAN Connectivity partners.
