Testing Service Function Chaining With Aticara

March 11, 2017

Aticara Introduction

Aticara is a completely software based and virtualized traffic simulator which can run on Commercial Off
the Shelf Hardware (COTS) and can generate line rate traffic both stateful and stateless.
Supported Hypervisors: ESX, KVM, Openstack
Supported Speeds: 1 /10/25/40/50/80/100 Gbps
(200 & 400 Gbps in roadmap)*

OVERVIEW

Service Function Chaining provides the ability to define an ordered list of network services (e.g., Firewall, NAT, QoS). These services are then stitched together in the network to create a service chain.

A service function chain defines anordered set of abstract service functions and orderingconstraints that must be applied to packets and/or frames and/orflows selected as a result of classification.  An example of an abstract service function is “a firewall”.  The implied order

may not be a linear progression as the architecture allows forSFCs that copy to more than one branch, and also allows forcases where there is flexibility in the order in which servicefunctions need to be applied.  The term “service chain” is oftenused as shorthand for service function chain.

Critical Components for deploying Service Plane in the Cloud

 

Classifier:  An element that performs Classification.

Service Function Chain (SFC):  A service function chain defines anordered set of abstract service functions and orderingconstraints that must be applied to packets and/or frames and/orflows selected as a result of classification.  An example of anabstract service function is “a firewall”.  The implied ordermay not be a linear progression as the architecture allows forSFCs that copy to more than one branch, and also allows forcases where there is flexibility in the order in which servicefunctions need to be applied.  The term “service chain” is oftenused as shorthand for service function chain.

 Service Function (SF):  A function that is responsible for specifictreatment of received packets.  A Service Function can act atvarious layers of a protocol stack (e.g., at the network layeror other OSI layers).  As a logical component, a service function can be realized as a virtual element or be embedded ina physical network element.  One or more Service Functions canbe embedded in the same network element.  Multiple occurrencesof the service function can exist in the same administrative domain. One or more service functions can be involved in the delivery ofadded-value services.  A non-exhaustive list of abstract servicefunctions includes: firewalls, WAN and application acceleration, Deep Packet Inspection (DPI), Lawful Intercept (LI), server loadbalancing etc.

Service Function Forwarder (SFF):  A service function forwarder isresponsible for forwarding traffic to one or more connected service functions according to information carried in the SFCencapsulation, as well as handling traffic coming back from theSF.  Additionally, an SFF is responsible for delivering trafficto a classifier when needed and supported, transporting trafficto another SFF (in the same or different type of overlay), andterminating the Service Function Path (SFP).

NSH, VxLAN GPE Header Support

Aticara can simulate millions of host behind Service Classifier, as well as simulate Service Classifier
itself by encapsulating the traffic generates by simulated host with in Network Service Header (NSH).
Aticara can also simulate Service Function Forwarder (SFF) by encapsulating NSH in VXLAN-GPE,
LISP and GENEVE

What scenarios can be tested with Aticara?

  • Functional and Performance testing of Service Classifier
  • Functional and Performance Testing of Service Function forwarder
  • Functional and Performance Testing of Service Function itself
  • Supported Encapsulations: NSH, VXLAN-GPE, GENEVE* and LISP*

What can Aticara simulate?

  • Hosts behind Service Classifier and Internet
  • Hosts behind Service Classifier, Service Classifier and Internet to Test Service Function Forwarder
  • Hosts behind Service Classifier & Internet, Service Classifier and Service Function Forwarder to test
    Service Function*
  • Aticara can also send statistics per host, service classifier, SFF statistics to the SDN Controller
    through its management port in JSON format periodically
    *