VNF BOF S. Hares Internet-Draft Hickory Hill Consulting Intended status: Informational February 14, 2014 Expires: August 18, 2014 Use Cases for Resource Pools with Virtual Network Functions (VNFs) draft-hares-vnf-pool-use-case-01 Abstract In the context of virtualization, a service essentially consists of a set of Virtualized Network Functions (VNFs) with each VNF building on top of virtualization infrastructure to implement a specific network functions along with the data connections between VNFs. VNFs may be highly distributed existing in devices in data center networks, mobile networks or satellite networks. In some of these environments, the resources are highly constrained. This draft provides seven use cases the author has observed in demonstrations or deployments for the following network function virtualization: cloud bursting, parental controls, load balancer for multipath (L1-L7), WAN optimization that runs either between access nodes and Data Centers, WAN optimization between mobile phones and Data Centers (through access nodes), application placement optimization, and optimized placement of web applications utilizing minimal data transfer. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on August 18, 2014. Hares Expires August 18, 2014 [Page 1] Internet-Draft vnf-pool-use-case February 2014 Copyright Notice Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Terms . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Use Case List . . . . . . . . . . . . . . . . . . . . . . 4 1.3. VNF Problems . . . . . . . . . . . . . . . . . . . . . . 4 2. Cloud Bursting Use Case . . . . . . . . . . . . . . . . . . . 6 3. Stateful Parental Controls . . . . . . . . . . . . . . . . . 7 4. Load balancer . . . . . . . . . . . . . . . . . . . . . . . . 8 5. Android phone TCP WAN optimization . . . . . . . . . . . . . 8 6. SOHO device optimization . . . . . . . . . . . . . . . . . . 9 7. application scaling . . . . . . . . . . . . . . . . . . . . . 10 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 9. Security Considerations . . . . . . . . . . . . . . . . . . . 11 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 10.1. Normative References . . . . . . . . . . . . . . . . . . 11 10.2. Informative References . . . . . . . . . . . . . . . . . 11 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 11 1. Introduction Certain network services within access networks, data center networks, and WAN networks are being virtualized. The service virtualization has been considered as part of the network function virtualization (NFV) or the Software Defined Networking (SDN) technology development. This draft focuses on the implementation of these network services using units of virtual network function (VNF) denoted as a VNF set where the each VNF is implemented as a pool of VNF instances. Each VNF builds its VNF instances on top of virtualized infrastructure to implement a specific network function (NF)connected to other network functions (NFs). Hares Expires August 18, 2014 [Page 2] Internet-Draft vnf-pool-use-case February 2014 For example, a VNF Firewall will have a pool of virtual firewall instances. When VNF instances are highly distributed, such as in a DC network or some access edge nodes for IP RAN - virtual function instances are built on a resource constraint environment where resource contention, hardware status change, hardware or software failures may occur. This introduction introduces the terms, lists deployed VNF use cases documented in this draft, and summarizes the problems that Virtual Network Function Pools have. 1.1. Terms The VNF Problem statement [I-D.zong-vnfpool-problem-statement] defines the terms reliability, VNF, VNF Pool, VNF Pool Element, VNF Pool User, VNF Pool Manager, and VNF Set. This draft uses these definitions. The following definitions are not defined within the VNF problem statement: Cloud Bursting, stateful parental controls, WAN optimization, and application placement. These terms are defined below. Cloud Bursting: the ability for Virtual processing to burst through the limits of one virtual environment and automatically transfers a portion of the processing to another virtual environment. Stateful parental controls: the ability for network access devices to have content filters that react to traffic, location, and user. These controls follow the user across multiple access points within a home network, or in a carrier network. WAN optimization: the ability to optimize traffic across a Wide-Area network. WAN optimization often makes use of TCP FLOW optimizations (with IETF TCP features) and TCP de-duplication of packets, Application placement: ability for coordinating software to place applications based a combination of compute resources, data storage, network service, and security concerns. Application placement may involve movement of some application data, movement of some applications (data and compute), and movement of network resources to service the applications. One type of network resource movement is the movement of virtual network functions (VNFs) which are defined, created, allocated with resources in a way to provide an integral unit to the application placement control software. OTT (Over the Top): This industry terms implies an overlay network that is overlaid on existing networks as a virtual network. Hares Expires August 18, 2014 [Page 3] Internet-Draft vnf-pool-use-case February 2014 1.2. Use Case List The use cases described in this draft are: o Cloud Bursting o stateful parental controls implemented in access nodes and firewalls (stateful and regular) o load balancer doing multipath (supports L1-L7 optimization), o WAN optimization between access nodes and Data Centers, o WAN optimization between mobile phones through access nodes to/ from Data center (E.g Riverbed WAN), o Application placement optimization using optimized DNS and DCHP VNFs, o Application placement optimization to minimize data transfer. Deployment of multi-vendor interoperability VNF services requires protocols and interfaces to VNF Pools that VNF Managers can access. Enterprises and Carriers have indicated their desire to allow the multi-vendor promise of SDN to be realized in the VNF functions. 1.3. VNF Problems VNF in constrained environments encounters the following types of problems: shared risk during VNF failures, VNF instance transition, backup and state synchronization of VNF within VNF sets, appropriate placement of VNF, reliable transport, and and multi-tenancy issues. (Note: The VNF Problem statement [I-D.zong-vnfpool-problem-statement] has not included multi-tenancy issues. Shared risk group Shared risk groups occur when different VNF instances are built on top of the same instance of a virtualized platform (E.g. hypervisor). When a hypervisor fails, all the VNF instances on the same hypervisor will fail, and service chains with this hypervisor VNFs in the remote chain will fail. Several concurrent services will fail when a hypervisor fails. If a fail and a restart occur quickly, it may placed substantial load on the network as effective VFN chains cause other nodes to be impacted. Hares Expires August 18, 2014 [Page 4] Internet-Draft vnf-pool-use-case February 2014 A VNF instance may encounter varying conditions on available resources during hypervisor load, resource contention from other VNFs, VMs or application programs running. The resources may be unavailable due contention with other programs placing load on the hypervisor, or hardware failures, software failure, or DOS. VNF instance transition If the VNF is unable to get the appropriate resources, the VNF meta- controller/manager may decide to migrate the function to another hypervisor or another portion of the network. Appropriate resources may include CPU resources, storage resources, special hardware resources, memory, and network resources. Another reason for varying conditions of resources is the need to add additional VNF to provide the appropriate level processing. For example, if additional in- depth analysis of a data pattern in a traffic flow was determine further security actions, another VNF set with DPI inspection and analysis might be created. Backup and state synchronization Backup systems are needed for any system requiring high reliability or high availability. Virtualized network services desired by customers may include network services critical to security of a network, user service levels, or insuring continued network availability during network outages. Planned network outages require transition of virtualized network services to other portions of the network. Transitions during planned outages have two cycles: transition before outage, transition after outage. Other than VNF transition, VNF instances will fail due to either hardware or software failure in various levels such as hypervisor, VM or even program. During a software failure, the VNF functions or group of functions may expand to synchronize state, handoff processes, and announce backup. This state synchronization may be limited to one hypervisor or spread across several hypervisors. Multi-tenancy When different users cohabitate the same VNFs or different VNFs cohabitate the same hypervisors, cohabitation may cause conflicts. Just as different human roommates sharing a common kitchen facilities, may have different traffic patterns so do different users utilizing the common VNFs. To stretch the metaphor, suppose one roommate wants to clean cooking pot immediately after use while the second roommate wants to wash cooking pots at the end of his/her cooking preparation. At some point, the roommates might contend for the sink to wash dishes. In the same way, data flows wanting to Hares Expires August 18, 2014 [Page 5] Internet-Draft vnf-pool-use-case February 2014 share a Deep Packet Inspection (DPI) engine may find that cohabitation in the multi-tenant DPI may cause issues. Different levels of reliability will also impact how multiple tenants share their resources. Resource pools allow both VNFs to get the common resource when desired by virtualizing it. 2. Cloud Bursting Use Case Description: Three cases of cloud bursting exist. Public clouds adding more resources upon demand. Private clouds adding more resources upon demand from private cloud resources. Private clouds adding more resources from the public cloud. In the public/private cloud, the orchestration system looks within pools of additional resources to fit the request for more resources for a particular time. Verizon provided examples of cloud bursing at ONS 2012, and Terremark utilizes cloud bursing to obtain more resources (http:// www.terremark.com/services/it-infrastructure/cloud-services/ enterprise-cloud/architecture/) operating over open-source hypervisors (2012, 2013). Resource pools with VMs that do a specific function (VNF or processing) within the operate to configure virtual switches, routers, and transport process (TCP/STCP) via standard interfaces (libvirt, CLI, REST, and JASON). The following is a list of functions may use that cloud bursting operators have been known to use pools for; o Virtual Machines (VMs) for application processing o VMs for remote storage drops o VMs for virtual firewall o VMS for DPI or DDOS o VMs specialized DNS that controls private/public cloud move o VMs for movement of data and applications within Cloud (Private/ Public) or between clouds o VMs for VPN to user Why VNF Pools: Bursty nature of action of Cloud Bursting requires being able to pre-allocate pools of VNF instances prior to use. Multi-vendor interoperable VNF Pools allows Data Center operators in Hares Expires August 18, 2014 [Page 6] Internet-Draft vnf-pool-use-case February 2014 Enterprise and Carriers to avoid the single-source for purchasing and single-code source software-bug failures. 3. Stateful Parental Controls Description: Parental content filters are targeted filters that are installed based on an identification of a user. When the centralized controller detects the User (via traffic pattern, role identification (ABFAB, HTTP)), SDN installs the appropriate software to guarantee filters. Two types of security exist: authentication and authorization. In authentication, ACL and other port based filtering is set per customer for the user. This filtering may block, prioritize, or transfer to a blackhole recording device different traffic. In authorization, the systems create a web of trust via an identity server (for HTTP 1.0 SAML template defined by OASIS and IETF ABFAB information for non-http). The following is a list of some of the VNFs associated who might use pool facilities: o VNF(s) for open source DPIs (snort, etc) o VNFs for specialized DPI inspection o VNFs for probes on hypervisors" o VNFs for depositing configuration in SDN OFS switches, and non-SDN switches, routers, firewalls, access nodes o VNF(s) for firewall o VNFs for DDOS o VNFs for specialized DNS/DHCP services after private/public cloud move o VNFs for movement within Cloud (Private/Public) or between clouds o VNF(s) for VPN to user identification Why VNF Pools: Bursty nature of user access that is data dependent requires being able to pre-allocate pools of services prior to use. Multi-vendor interoperable VNF Pools Enterprise and Carriers to avoid the single-source access devices for purchasing and single-code source software-bug failures in access nodes. Hares Expires August 18, 2014 [Page 7] Internet-Draft vnf-pool-use-case February 2014 4. Load balancer Description: Load balancers (such as Riverbed or Cisco) look to balance traffic different layers of the stack (L1-L7). SDN meta controllers (OpenDaylight, Vyatta) monitor work with the time-critical OTT control process (which creates and manages the OTT VPNs (L2/L3/MPLS)) to determine where the load is at any specific time, and to track it over time. The SDN orchestrators work with the SDN OTT control process to adjust to readjust the load at L1-L7. The VNF functions that use resource pools in the load balancing service are: o VNFs for probes in all devices (mobile phone, ipad, access devices, vswitch, vrouter, tcp optimizer, DPI, hypervisors, VMs dumming storage, VMs creating the network; o VNFs for depositing configuration in SDN OFS switches, and non-SDN switches, routers, firewalls, access nodes; o VNFs for firewall; o VNFs for Traffic capacity/load balance calculation; o VNFs running orchestrator monitor/change algorithms; o VNFs for traffic movement within Cloud (Private/Public) or between clouds to balance load; and o VNFs for VPN to user identification. Why VNF Pools: True end-to-end Load balancing requires a load balancing across multiple layers. with VNF pools to support different functions. Multi-vendors solutions will allow meta controllers to balance traffic to reduce costs in networks. Current Enterprise customers find the load balancing operates with TCP WAN optimization to utilize all network bandwidth effectively. 5. Android phone TCP WAN optimization Description: Android phones and Android tablets often communicate across the LTE/ WiFi connections. Optimization of the link for the low-bandwidth of LTE or Wifi connections, and the switch between LTE and WiFi requires Hares Expires August 18, 2014 [Page 8] Internet-Draft vnf-pool-use-case February 2014 monitoring of traffic, choosing link, optimizing TCP (Window and removing duplicates). The VNFs that use resource pools in this application include: o VNFs for probes in all devices (mobile phone, mobile pads, Wifi enabled nodes, LTE IP RAN notes) o VNFs for depositing configuration in SDN access nodes (Wifi or LTE) o VNFs for to handle remote phone parameter adjustments; o VNFs to do firewalls (E.g traffic not allowed over LTE due to customer policy); o VNFs for TCP data de-duplication process; o VNFs for Traffic capacity/load balance calculation (see Football stadium problem below); o VNFs for best processing of Video traffic or best network to pull Video traffic from; o VNFs for VMs for VPN to user identification; and o VNFs to interface to secure data processes. One scenario to consider is the football stadium scenario. A person takes the IPAD to watch the close up replays or send email. During fourth quarter, the person receive an urgent call to go home and walks with the IPAD down the street to the metro-system to return home. On the way, the person is utilizing the IPAD to send mail, watch the football game, and do Skype calls. Why VNF Pools: Phones systems do not want a single vendor for all features. Multiple interoperable access nodes and Android pad/tablet implementations require these VNF pools. 6. SOHO device optimization Description: SOHO devices using SDN VM technology must balance traffic movement between small cells (WiFi or femtocells). Access policies must be configured for restriction on this policy. The VNFs that use resource pools in this application are: Hares Expires August 18, 2014 [Page 9] Internet-Draft vnf-pool-use-case February 2014 o VNFs for probes in all devices (mobile phone, mobile pads, WiFi enabled nodes, LTE or femtocells) o VNFs for depositing configuration in SDN access nodes (Wifi, L), VNFs for handling remote phone parameter adjustments; o vNFs for firewall (traffic not allowed over LTE); o VNFs for TCP data de-duplication process; o VNFs for Traffic capacity/load balancing over single/multiple soho links; o VNFs to allow applications load balance across internal soho links based on traffic needs and use policy; and o VNFs for VPN to user identification and security. Why VNF Pools: SOHO devices often need to be plug and play for different types of users. Common VNF Pools allows development of interoperable devices that can plug and play under a SOHO controller. 7. application scaling Description: Applications may be placed in a variety of hypervisors. The rapid deployment of applications on services may allow millions of applications to be available within the cloud. Creating a effective lookup for the applications or redirecting applications takes an Network Virtual environment that controls DCHP, DNS, and http access rapidly. 2 Million URI references for each access node is possible given the current growth. VNF within the cloud must scale up to handle the VNF services required by the network infrastructure. This includes the network information functions of DNS, DCHP, URL processing, AAA (Diameter/ Radius). Fast enactment of these network functions allows an on- demand creation of a multi-tennancy overlay (IETF NV03). The VNFs that use resource pools in this application are: o VNFs for AAA functions (Diameter, Radius); o VNFs for DNS functions; o VNFs for DCHP functions Hares Expires August 18, 2014 [Page 10] Internet-Draft vnf-pool-use-case February 2014 o VNFs for specialized URL/URI processing; o VNFs for handling remote probes on these virtual information functions; o VNFs for handling remote configuration of these virtual information functions; o VNFs for Traffic capacity/load balance calculation; o VNFs for determine optimum deployment of full VMs for application or determination if data transfer to an existing application (Java Application data); o VNFs for VPN to user identification and permissions to use data; and o VNFs to determine back-up placements for applications 8. IANA Considerations This document includes no request to IANA. 9. Security Considerations This document has no security issues as just contains use cases. 10. References 10.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 10.2. Informative References [I-D.zong-vnfpool-problem-statement] Zong, N., Dunbar, L., Shore, M., and D. Lopez, "Virtualized Network Function (VNF) Pool Problem Statement", draft-zong-vnfpool-problem-statement-02 (work in progress), January 2014. Author's Address Hares Expires August 18, 2014 [Page 11] Internet-Draft vnf-pool-use-case February 2014 Susan Hares Hickory Hill Consulting 7453 Hickory Hill Saline, CA 48176 USA Email: shares@ndzh.com Hares Expires August 18, 2014 [Page 12]