Patent Publication Number: US-2023135386-A1

Title: Remote cost based network traffic steering for heterogeneous links in a sdwan (software defined wide area network)

Description:
FIELD OF THE INVENTION 
     The invention relates generally to computer networking, and more specifically, to steering network traffic on heterogenous links in SDWAN based on remote cost. 
     BACKGROUND 
     The state-of-art secured SD-WAN (Software Defined Wide Area Network) steers traffic among IPSEC (Internet Protocol security) tunnels. It is an Internet Engineering Task Force (IETF) standard suite of protocols between 2 communication points across the IP network that provide data authentication, integrity, and confidentiality. It also defines the encrypted, decrypted and authenticated packets. 
     However, although these IPSEC tunnels are logically consistent from the view of SDWAN, they are built on heterogeneous physical links. The local end of a tunnel could be built on the high speed broadband link, while the remote end is built on the LTE (long-term evolution) wireless link. This tunnel is expected to get a lower priority to steer traffic because LTE could incur expensive cost although it may keep a good quality. Unfortunately, the local SDWAN has no knowledge of the remote end. The knowledge cannot be acquired by the current quality detection techniques, such as sending probes periodically, either. Customers are calling for an innovation to guide the SDWAN to steer traffic based on the remote end&#39;s information. 
     Therefore, what is needed is a robust technique for steering network traffic on heterogenous links in SDWAN based on remote cost. 
     SUMMARY 
     These shortcomings are addressed by the present disclosure of methods, computer program products, and systems for steering network traffic on heterogenous links in SDWAN based on remote cost. 
     In an embodiment, a health check is generated for at least two member paths between the local SDWAN controller and a remote SDWAN controller, with a set health check probe packets for transmission by the network interface to remote SDWAN controllers. The at least two member paths have heterogenous physical attributes. 
     In another embodiment, a link cost is determined for each member path from a set of health check response packets received by the network interface. A remote link cost reflective of physical attributes for a particular link is appended by the remote SDWAN controller to a particular health check response packet. 
     In still another embodiment, the process is finalized by prioritizing SDWAN network traffic for each member path between the local SDWAN controller and the remote SDWAN controller based at least in part on the link cost. 
     Advantageously, computer network performance is improved. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the following drawings, like reference numbers are used to refer to like elements. Although the following figures depict various examples of the invention, the invention is not limited to the examples depicted in the figures. 
         FIG.  1    is a high-level block diagram illustrating a system for steering network traffic on heterogenous links in SDWAN based on remote cost, according to an embodiment. 
         FIG.  2    is a more detailed block diagram illustrating an SDWAN controller the system of  FIG.  1   , according to an embodiment. 
         FIG.  3    is a block diagram illustrating a health check probe packet for SDWAN, according to an embodiment. 
         FIG.  4    is a high-level flow diagram illustrating a method for steering network traffic on heterogenous links in SDWAN based on remote cost, according to an embodiment. 
         FIG.  5    is a more detailed flow diagram illustrating a step of prioritizing SDWAN network traffic of the method of  FIG.  4   , according to an embodiment. 
         FIG.  6    is a general computing environment for implementing the system of  FIG.  1   , according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The description below provides methods, computer program products, and systems for steering network traffic on heterogenous links in SDWAN based on remote cost. 
     One of ordinary skill in the art will recognize many additional variations made possible by the succinct description of techniques below. 
     I. Systems for SDWAN Link Traffic Prioritizing ( FIGS.  1 - 3   ) 
       FIG.  1    is a high-level illustration of a system  100  for steering network traffic on heterogenous links in SDWAN based on remote cost, according to an embodiment. A local SDWAN controller  110 A is coupled to Remote SDWAN controllers  120 B,C. Local and remote are relative terms depending on which side of the SDWAN is building VPNs (Virtual Private Networks). Many variations are possible, including additional (or single) SDWAN controllers, access points, gateways, router, switches, firewalls, and other network components. 
     The components of the system  100  are coupled in communication over the data communication network  199 . Preferably, the access point  110  connected to the data communication system via hard wire, such as local SDWAN controller  110 A, remote SDWAN controllers  110 B,C and station  120 C. Other components, such as the headless IoT devices can be connected indirectly via wireless connection, such as stations  120 A,B. The data communication network  199  can be any data communication network such as an SDWAN, an SDN (Software Defined Network), WAN, a LAN, WLAN, a cellular network (e.g., 3G, 4G, 5G or 6G), or a hybrid of different types of networks. Various data protocols can dictate format for the data packets. For example, Wi-Fi data packets can be formatted according to IEEE 802.11. 
     In one embodiment, the local SDWAN controller  110 A includes a traffic cost prioritizer  112  to determine a cost for each heterogenous remote link available for routing, without having direct visibility. During a health check for links with remote SDWAN controllers  110 B,C, a remote cost is also identified. Heterogeneous links can have different costs. For example, a first VPN may be a broadband link  102  assigned a cost of 10 while a second VMP may be a much slower LTE link  103  is assigned a cost of 100. Other types of links can also have different cost assignments. As a result, the local SDWAN controller  110 A prioritizes network traffic based on the remote cost. Higher cost traffic over the LTE link  103  may be deprioritized relative to traffic over the broadband link  102 , or others. 
     The local SDWAN controller  110 A and the remote SDWAN controllers  110 B,C can be a sever blade in an array of server blades, a PC (personal computer), a mobile computing device, a laptop device, a smartphone, a tablet device, a phablet device, a video game console, a stationary computing device, an Internet appliance, a virtual computing device, a distributed computing device, a cloud-based computing device, or any appropriate processor-driven device. Physical attributes of a local link are known to the local SDWAN controller  110 A, however, physical attributes of remote links are unknown until probed. More details about SDWAN controllers are set forth below with respect to  FIG.  2   . 
     The remote SDWAN controller  110 B,C receives health check requests from the local SDWAN controller  110 A and others. More specifically, a health check probe request is received from the local SDWAN controller  110 A requesting details about back-end links managed by the remote SDWAN controller  110 B,C because the local SDWAN controller  110 A has no visibility. The requested details can include, for each link, latency, jitter, and packet loss. In addition, details are requested about remote links. In one embodiment, a configuration file  114  is updated in the remote SDWAN controller  110 B,C by a network administrator to include remote costs. One example of the configuration file is as follows: 
     
       
         
           
               
               
             
               
                   
                   
               
             
            
               
                   
                 config system sdwan 
               
               
                   
                  config member 
               
               
                   
                  edit 1 
               
               
                   
                  set interface broadband 
               
               
                   
                  set cost 10 -------------------- The cost reflects the 
               
               
                   
                  attribute of member link 
               
               
                   
                  next 
               
               
                   
                  edit 2 
               
               
                   
                  set interface LTE 
               
               
                   
                  set cost 100 
               
               
                   
                  next 
               
               
                   
                 end 
               
               
                   
                   
               
            
           
         
       
     
     The stations  120 A,B,C are end points, such as a user with a laptop or a smartphone. Stations  120  and  120 B are wirelessly connected to the backbone network while station  130 C is connected by wire. Although stations  120 A and  120 B can be geographically separated from station  120 C, SDWAN provides a virtual interface that substantially negates the geographical separation. For instance, station  120 A may interact with station  120 C in the same capacity as station  120 B. Link quality is thus an important factor in maintaining the virtual interface. 
       FIG.  2    is a more detailed block diagram illustrating the local SDWAN controller  110  of the system  100  of  FIG.  1   , according to one preferred embodiment. The local SDWAN controller  110  comprises a health check module  210 , a link cost determination module  220 , and SDWAN traffic prioritizer  230 . 
     In an embodiment, the health check module  210  can generate a health check for at least two member paths between the local SDWAN controller and a remote SDWAN controller, with a set health check probe packets for transmission by the network interface to remote SDWAN controllers. Probes can be sent periodically or triggered by events (e.g., a new SDWAN, or network update). The at least two member paths have heterogenous physical attributes. 
     One example of a health check probe is shown in  FIG.  3   . The health check probe  300  comprises a header field  310 , a time stamp field  320 , and a cost field  330 . The time stamp field  320  can be 8 bytes while the cost field  330  is 4 bytes in this case. Other values are possible. The cost field  330  field can be padded into the health check probe  300 . One way of doing this is having an offset define a field within a data field, or other field. 
     Referring again to  FIG.  2   , the link cost module  220  determines a link cost for each member path from a set of health check response packets received by the network interface. A remote link cost reflective of physical attributes for a particular link is appended by the remote SDWAN controller to a particular health check response packet. 
     The SDWAN traffic prioritizer  230  finalizes the process by steering SDWAN network traffic for each member path between the local SDWAN controller and the remote SDWAN controller based at least in part on the link cost. In one instance, if the quality of tunnel A or tunnel B are better, the best is chosen. However, if the quality is similar or equal, a cost may be considered as the deciding factor. Similar or equal costs could then lead selection to a configuration order. 
     II. Methods SDWAN Link Traffic Prioritizing ( FIG.  4 - 5   ) 
       FIG.  4    is a high-level flow diagram illustrating a method for steering network traffic on heterogenous links in SDWAN based on remote cost, according to one embodiment. The method  300  can be implemented, for example, by the system  100  of  FIG.  1   . The steps are merely representative groupings of functionality, as there can be more or fewer steps, and the steps can be performed in different orders. Many other variations of the method  400  are possible. 
     At step  410 , In an embodiment, a health check is generated for at least two member VPN paths between the local SDWAN controller (e.g., spoke  1 ) and a remote SDWAN controller (e.g., spoke  2 ), with a set health check probe packets for transmission by the network interface to remote SDWAN controllers. The at least two member VPN paths have heterogenous physical attributes. 
     At step  420 , a link cost is determined for each member path from a set of health check response packets received by the network interface. A remote link cost reflective of physical attributes for a particular link is appended by the remote SDWAN controller to a particular health check response packet. 
     At step  430 , the process is finalized by prioritizing SDWAN network traffic for each member path between the local SDWAN controller and the remote SDWAN controller based at least in part on the link cost. An example prioritization algorithm is shown in  FIG.  5   . At step  510 , if the quality of tunnel A or tunnel B is better, a choice is made as select A  501  or select B  502 . Responsive to similar or equal quality, a cost of tunnel A is compared against a cost of tunnel B, and a smaller cost can be chosen at this point as select A  501  or select B  502 . At step  530 , if the costs are equal or similar, a tunnel selection (e.g., IPSEC tunnel) can be based on configuration order. 
     III. Generic Computing Environment ( FIG.  6   ) 
       FIG.  6    is a block diagram of a computing environment  600 , according to an embodiment. The computing environment  600  includes a memory  605 , a processor  622 , a storage drive  630 , and an I/O port  640 . Each of the components is coupled for electronic communication via a bus  699 . Communication can be digital and/or analog and use any suitable protocol. The computing environment  600  can be a networking device (e.g., the local SDWAN controller  110 A, the remote SDWAN controllers  110 B,C, an access point, a firewall device, a gateway, a router, or a wireless station). 
     The memory  610  further comprises network applications  612  and an operating system  614 . The network applications  612  can include a web browser, a mobile application, an application that uses networking, a remote application executing locally, a network protocol application, a network management application, a network routing application, or the like. 
     The operating system  614  can be one of the Microsoft Windows® family of operating systems (e.g., Windows 96, 98, Me, Windows NT, Windows 2000, Windows XP, Windows XP ×64 Edition, Windows Vista, Windows CE, Windows Mobile, Windows 6 or Windows 8), Linux, HP-UX, UNIX, Sun OS, Solaris, Mac OS X, Alpha OS, AIX, IRIX32, IRIX64, or Android. Other operating systems may be used. Microsoft Windows is a trademark of Microsoft Corporation. 
     The processor  622  can be a network processor (e.g., optimized for IEEE 802.11, IEEE 802.11AC or IEEE 802.11AX), a general-purpose processor, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a reduced instruction set controller (RISC) processor, an integrated circuit, or the like. Qualcomm Atheros, Broadcom Corporation, and Marvell Semiconductors manufacture processors that are optimized for IEEE 802.11 devices. The processor  622  can be single core, multiple core, or include more than one processing elements. The processor  622  can be disposed on silicon or any other suitable material. The processor  622  can receive and execute instructions and data stored in the memory  222  or the storage drive  630 . 
     The storage drive  630  can be any non-volatile type of storage such as a magnetic disc, EEPROM (electronically erasable programmable read-only memory), Flash, or the like. The storage drive  630  stores code and data for applications. 
     The I/O port  640  further comprises a user interface  642  and a network interface  644 . The user interface  642  can output to a display device and receive input from, for example, a keyboard. The network interface  644  (e.g., an RF antennae) connects to a medium such as Ethernet or Wi-Fi for data input and output. Many of the functionalities described herein can be implemented with computer software, computer hardware, or a combination. 
     Computer software products (e.g., non-transitory computer products storing source code) may be written in any of various suitable programming languages, such as C, C++, C#, Oracle® Java, JavaScript, PHP, Python, Perl, Ruby, AJAX, and Adobe® Flash®. The computer software product may be an independent application with data input and data display modules. Alternatively, the computer software products may be classes that are instantiated as distributed objects. The computer software products may also be component software such as Java Beans (from Sun Microsystems) or Enterprise Java Beans (EJB from Sun Microsystems). Some embodiments can be implemented with artificial intelligence. 
     Furthermore, the computer that is running the previously mentioned computer software may be connected to a network and may interface with other computers using this network. The network may be on an intranet or the Internet, among others. The network may be a wired network (e.g., using copper), telephone network, packet network, an optical network (e.g., using optical fiber), or a wireless network, or any combination of these. For example, data and other information may be passed between the computer and components (or steps) of a system of the invention using a wireless network using a protocol such as Wi-Fi (IEEE standards 802.11, 802.11a, 802.11b, 802.11e, 802.11g, 802.11i, 802.11n, and 802.11ac, just to name a few examples). For example, signals from a computer may be transferred, at least in part, wirelessly to components or other computers. 
     In an embodiment, with a Web browser executing on a computer workstation system, a user accesses a system on the World Wide Web (WWW) through a network such as the Internet. The Web browser is used to download web pages or other content in various formats including HTML, XML, text, PDF, and postscript, and may be used to upload information to other parts of the system. The Web browser may use uniform resource identifiers (URLs) to identify resources on the Web and hypertext transfer protocol (HTTP) in transferring files on the Web. 
     The phrase “network appliance” generally refers to a specialized or dedicated device for use on a network in virtual or physical form. Some network appliances are implemented as general-purpose computers with appropriate software configured for the particular functions to be provided by the network appliance; others include custom hardware (e.g., one or more custom Application Specific Integrated Circuits (ASICs)). Examples of functionality that may be provided by a network appliance include, but is not limited to, layer ⅔ routing, content inspection, content filtering, firewall, traffic shaping, application control, Voice over Internet Protocol (VoIP) support, Virtual Private Networking (VPN), IP security (IPSec), Secure Sockets Layer (SSL), antivirus, intrusion detection, intrusion prevention, Web content filtering, spyware prevention and anti-spam. Examples of network appliances include, but are not limited to, network gateways and network security appliances (e.g., FORTIGATE family of network security appliances and FORTICARRIER family of consolidated security appliances), messaging security appliances (e.g., FORTIMAIL family of messaging security appliances), database security and/or compliance appliances (e.g., FORTIDB database security and compliance appliance), web application firewall appliances (e.g., FORTIWEB family of web application firewall appliances), application acceleration appliances, server load balancing appliances (e.g., FORTIBALANCER family of application delivery controllers), vulnerability management appliances (e.g., FORTISCAN family of vulnerability management appliances), configuration, provisioning, update and/or management appliances (e.g., FORTIMANAGER family of management appliances), logging, analyzing and/or reporting appliances (e.g., FORTIANALYZER family of network security reporting appliances), bypass appliances (e.g., FORTIBRIDGE family of bypass appliances), Domain Name Server (DNS) appliances (e.g., FORTIDNS family of DNS appliances), wireless security appliances (e.g., FORTIWIFI family of wireless security gateways), FORIDDOS, wireless access point appliances (e.g., FORTIAP wireless access points), switches (e.g., FORTISWITCH family of switches) and IP-PBX phone system appliances (e.g., FORTIVOICE family of IP-PBX phone systems). 
     This description of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications. This description will enable others skilled in the art to best utilize and practice the invention in various embodiments and with various modifications as are suited to a particular use. The scope of the invention is defined by the following claims.