report: edits in aws methodology section

Edits include:
- add description of used testbed topologies.
- cleaned up references.
- other editing nits.

Change-Id: I43069541f3da8e844529a00a127fb1a360197647
Signed-off-by: Maciek Konstantynowicz <mkonstan@cisco.com>

1 files changed, 50 insertions, 29 deletions

diff --git a/docs/report/introduction/methodology_aws/aws_instances.rst b/docs/report/introduction/methodology_aws/aws_instances.rst
index 0df0321c5f..18ae659de3 100644
--- a/docs/report/introduction/methodology_aws/aws_instances.rst
+++ b/docs/report/introduction/methodology_aws/aws_instances.rst
@@ -1,22 +1,40 @@
-Instances
----------
+AWS Performance Testbeds
+------------------------
 
-CSIT is using C5n instances for high compute applications that can take
-advantage of improved network throughput and packet rate performance. C5n
-instances offers up to 100 Gbps network bandwidth and increased memory over
-comparable C5 instances [aws_it]_.
+CSIT implements two virtual machine topology types running in AWS EC2:
 
-Features:
+- **2-Node Topology**: Consists of one EC2 instance as a System Under
+  Test (SUT) and one EC2 instance acting as a Traffic Generator
+  (TG), with both instances connected into a ring topology. Used for
+  executing tests that require frame encapsulations supported by TG.
 
-- 3.0 GHz Intel Xeon Platinum processors with Intel Advanced Vector Extension
-  512 (AVX-512) instruction set.
-- Sustained all core Turbo frequency of up to 3.4GHz, and single core turbo
-  frequency of up to 3.5 GHz.
-- Requires HVM AMIs that include drivers for ENA and NVMe [aws_ena]_.
-- Network bandwidth increases to up to 100 Gbps, delivering increased
-  performance for network intensive applications.
-- Powered by the AWS Nitro System, a combination of dedicated hardware and
-  lightweight hypervisor.
+- **3-Node Topology**: Consists of two EC2 instances acting as a Systems
+  Under Test (SUTs) and one EC2 instance acting as a Traffic Generator
+  (TG), with all instances connected into a ring topology. Used for
+  executing tests that require frame encapsulations not supported by TG
+  e.g. certain overlay tunnel encapsulations and IPsec.
+
+AWS EC2 Instances
+-----------------
+
+CSIT is using AWS EC2 C5n instances as System Under Test and TG virtual
+machines. C5n instances got selected to take advantage of high network
+throughput and packet rate performance. C5n instances offer up to 100
+Gbps network bandwidth and increased memory over comparable C5
+instances. For more information, see
+`Instance types <https://aws.amazon.com/ec2/instance-types/>`_.
+
+C5n features:
+
+- 3.0 GHz Intel Xeon Platinum (Skylake) processors with Intel AVX-512
+  instructions.
+- Sustained all core Turbo frequency of up to 3.4GHz, and single core
+  turbo frequency of up to 3.5 GHz.
+- Requires HVM AMIs (Amazon Machine Images) that include drivers for ENA
+  and NVMe. See :ref:`csit_ami` for more information.
+- Network bandwidth to up to 100 Gbps.
+- Powered by the AWS Nitro System, a combination of dedicated hardware
+  and lightweight hypervisor.
 
 +-------------+------+--------------+------------------------+-----------------------------+----------------------+
 | Model       | vCPU | Memory (GiB) | Instance Storage (GiB) | Network Bandwidth (Gbps)*** | EBS Bandwidth (Mbps) |
@@ -36,21 +54,24 @@ Features:
 |c5n.metal    |   72 |       192    |        EBS-Only        |                         100 |               19,000 |
 +-------------+------+--------------+------------------------+-----------------------------+----------------------+
 
-CSIT is configured by default to use `c5n.4xlarge` in `eu-central-1` AWS region
-due to allocation stability issues with `c5n.9xlarge` in `eu-central-1` region.
+CSIT is configured by default to use `c5n.4xlarge` in `eu-central-1` AWS
+region due to allocation stability issues with `c5n.9xlarge` in
+`eu-central-1` region.
 
 
-AWS Elastic Network Adapter (ENA)
----------------------------------
+AWS EC2 Networking
+------------------
 
-Enhanced networking uses single root I/O virtualization (SR-IOV) to provide
-high-performance networking capabilities on supported instance types. SR-IOV is
-a method of device virtualization that provides higher I/O performance and lower
-CPU utilization when compared to traditional virtualized network interfaces
-[aws_ena]_.
+CSIT EC2 instances are equipped with AWS Elastic Network Adapter
+(ENA) supporting AWS enhanced networking. Enhanced networking uses
+single root I/O virtualization (SR-IOV) to provide high-performance
+networking capabilities. For more information, see
+`Elastic Network Adapter <https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/enhanced-networking-ena.html>`_.
 
-Current advertised limits are captured in [aws_limits]_.
+For more information about the current advertised AWS ENA performance
+limits, see
+`Computed optimized instances <https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/compute-optimized-instances.html>`_.
 
-.. [aws_it] `Instance types <https://aws.amazon.com/ec2/instance-types/>`_
-.. [aws_ena] `Elastic Network Adapter <https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/enhanced-networking-ena.html>`_
-.. [aws_limits] `<https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/compute-optimized-instances.html>`_
\ No newline at end of file
+CSIT DUTs make use of AWS ENA DPDK driver supplied by AWS and specified
+in
+`amzn drivers dpdk <https://github.com/amzn/amzn-drivers/tree/master/userspace/dpdk>`_.