Palo Alto Networks supports an SD-WAN overlay that provides dynamic, intelligent path selection based on applications, services, and link conditions.
Software-Defined Wide Area Network (SD-WAN) is a technology that allows you to use multiple internet and private services to create an intelligent and dynamic WAN, which helps lower costs and maximize application quality and usability. Beginning with PAN-OS
®9.1, Palo Alto Networks
®offers strong security with an SD-WAN overlay in a single management system. Instead of using costly and time-consuming MPLS with components such as routers, firewalls, WAN path controllers, and WAN optimizers to connect your WAN to the internet, SD-WAN on a Palo Alto Networks firewall allows you to use less expensive internet services and fewer pieces of equipment. You don’t need to purchase and maintain other WAN components.
with SD-WAN Functionality
The SD-WAN plugin is integrated with PAN-OS, so that you get the security features of a PAN-OS firewall and SD-WAN functionality from a single vendor. The SD-WAN overlay supports dynamic, intelligent path selection based on applications and services and the conditions of links that each application or service is allowed to use. The path health monitoring for each link includes latency, jitter, and packet loss. Granular application and service controls allow you to prioritize applications based on whether the application is mission-critical, latency-sensitive, or meets certain health criteria, for example. Dynamic path selection avoids brownout and node failure problems because sessions fail over to a better performing path in less than one second.
The SD-WAN overlay works with all PAN-OS security features, such as User-ID™ and App-ID™, to provide complete security control to branch offices. The full suite of App-ID capabilities (App-ID decoder, App-ID cache, and source/destination external dynamic list [EDL] IP address lists) identifies applications for application-based control of SD-WAN traffic. You can deploy the firewall with Zero Trust segmentation of traffic. You can configure and manage SD-WAN centrally from the Panorama web interface or the Panorama REST API.
You may have cloud-based services and instead of having your internet traffic flow from branches to the hub to the cloud, you want the internet traffic to flow directly from branches to the cloud using a directly connected ISP. Such access from a branch to the internet is Direct Internet Access (DIA). You don’t need to spend your hub bandwidth and money on internet traffic. The branch firewall is already doing security, so you don’t need the hub firewall to enforce security on internet traffic. Use DIA on branches for SaaS, web browsing, or heavy-bandwidth applications that shouldn’t be backhauled to a hub. The following figure illustrates a DIA virtual interface consisting of three links from the branch to the cloud. The figure also illustrates a VPN tunnel virtual interface consisting of four links that connect the branch to the hub at the headquarters.
Link and Firewall Support
Link bundling allows you to group multiple physical links (that different ISPs use to communicate with the same destination) into a virtual SD-WAN interface. On the basis of applications and services, the firewall chooses from the links (path selection) for session load sharing and to provide failover protection in the event of a brownout or blackout. Thus you are providing the application with the best quality performance. The firewall automatically performs session load sharing over the links in a virtual SD-WAN interface to use available bandwidth advantageously. An SD-WAN interface must have all of the same type of connection (either DIA or VPN). VPN links support the hub-and-spoke topology.
SD-WAN supports the following types of WAN connections: ADSL/DSL, cable modem, Ethernet, fiber, LTE/3G/4G/5G, MPLS, microwave/radio, satellite, WiFi, and anything that terminates as Ethernet to the firewall’s interface. You decide the appropriate strategy for how to use the links. You could use inexpensive broadband connections before expensive MPLS or LTE connections. Alternatively, you could use specific VPN tunnels to reach specific hubs in a region.
PA-220, PA-220R, PA-820, and PA-850 firewalls are supported as SD-WAN branch firewalls. PA-3200 Series, PA-5200 Series, VM-300, VM-500, and VM-700 firewalls are supported as SD-WAN hub firewalls. Each firewall (branch or hub) requires an SD-WAN subscription. Each Panorama requires the SD-WAN plugin.
If you are a new customer purchasing a Palo Alto Networks next-generation firewall, you will use the default virtual router for SD-WAN. If you are an existing customer, you can choose to either let PAN-OS overwrite any existing virtual routers or use a new virtual router and new zones for SD-WAN to keep SD-WAN content separate from your pre-existing configuration.
Panorama™ provides the means to configure and manage SD-WAN, which makes configuring multiple options on many geographically-dispersed firewalls much faster and easier than configuring firewalls individually. You can change network configurations from a single location rather than configuring each firewall individually. Auto VPN configuration allows Panorama to configure branches and hubs with secure IKE/IPSec connections. A VPN cluster defines the hubs and branches that communicate with each other in a geographic region. The firewall uses VPN tunnels for path health monitoring between a branch and a hub to provide subsecond detection of brownout conditions.
The Panorama dashboard provides visibility into your SD-WAN links and performance so that you can adjust path quality thresholds and other aspects of SD-WAN to improve its performance. Centralized statistics and reporting include application and link performance statistics, path health measurements and trend analysis, and focused views of application and link issues.
Begin by understanding your SD-WAN use case, then review the SD-WAN configuration elements, traffic distribution methods, and plan your SD-WAN configuration. To greatly accelerate the configuration, the best practice is for you to export an empty SD-WAN device CSV and enter information such as branch office IP address, the virtual router to use, the firewall site name, zones to which the firewall belongs, and BGP route information. Panorama uses the CSV file to configure the SD-WAN hubs and branches and to automatically provision VPN tunnels between hubs and branches. SD-WAN supports dynamic routing through eBGP and is configured using Panorama’s SD-WAN plugin to allow all branches to communicate with the hub only or with the hub and other branches.