ENERGY STAR® Notes on Small Network
Equipment Dataset

This document provides a description of steps EPA has taken in analysis of the Small NetworkEquipment Dataset. The dataset, with manufacturer names masked, is available on the ENERGYSTAR website.

I.

Analysis Overview

Draft 1 presents an Average Power Consumption (PAVG) structure as the primary energy
efficiency metric in the Small Network Equipment specification. In this approach, an average
power value for a product is derived from all applicable data points out of the following:•PWAN_TEST: Measured power consumption in Wired Network – WAN test, at 1.0 kb/s (W);

•PLAN_TEST: Measured power consumption in Wired Network – LAN test, half of available
wired LAN ports populated, at 1.0 kb/s (W); and•

PWIRELESS_TEST = Measured power consumption in Wireless Network – LAN test, at 1.0kb/s (W).
A limited list of functional power adders were considered in order to allow proposed levels toaccount for scaling by Ethernet Port and the presence of Wi-Fi in categories where it was present
in some, but not all, devices.

II.

Dataset Overview:A.

EPA reviewEPA reviewed data acquired using both the Rev 2 and Rev 4 Test methods. Asummary of the changes between the two versions is provided below as areference.

Table 1: Comparison of Rev 2 and Rev 4 Test Methods
WANTesting•

WiredLAN••

WirelessLAN••

V2
Measurements taken withtraffic at 7 speeds, asapplicable to the UUT
Three scenarios: minimum, half-, and full-ports
connected
For each scenario,
measurements taken withtraffic at 4 speeds, asapplicable to the UUT
Measurements taken withtraffic at 4 speeds, asapplicable to the UUT
Tests repeated for eachavailable wireless protocol

••
•

••

V4Measurements taken with traffic at
2 speeds, 1 kb/s and a high traffic
rate as specified in Table 8
One scenario: half-ports connected
For the half-port scenario,
measurements taken with traffic at
2 speeds, 1 kb/s and a high traffic
rate as specified in Table 8

Measurements taken with traffic at
2 speeds, 1 kb/s and a high traffic
rate as specified in Table 8
Tests repeated for each available
wireless protocol

EPA focused on power consumption at low data rates. To account for differencesin the test method revisions, idle power was analyzed in instances where data
was not taken for the 1 kb/s condition. PAVG was calculated by averaging all nonzero values of PWAN_TEST, PLAN_TEST, and PWIRELESS_TEST. To allow for anappropriate evaluation of base consumption, adder values were subtracted fromthis average. This adjusted value was used to set the base product typerequirements.
EPA completed the initial data review with an evaluation of the product types
listed for each data point. To account for instances where ambiguities in the initial
set of ENERGY STAR definitions were present, EPA recategorized as
appropriate for a subset of products. Both original manufacturer disclosures(column L) and EPA’s revisions (column N) remain listed in the public dataset fileshould further review be required.
B.

Functional Adder Values
The following table summarizes functional adders assigned in Draft 1. Thesevalues were set after review of multiple sources that included program data andout-year tiers in the European Commission’s Broadband Code of Conduct
Version 4.

Table 2: Functional Adder Values
FeatureFast Ethernet(100Base-T)

C.

PowerAllowance (PADD)
in watts
0.1

Gigabit Ethernet(1000Base-T)

0.3

Wi-Fi
(802.11a/b/g/n)

0.7

Notes

Allowance applied
once per port
present in theUUT.
Allowance applied
once per port
present in theUUT.
Applied once for
the UUT for
availability of WiFi connectivity.

DatasetThe charts in this section present data received in each product area, excluding
categories in which data was insufficient to support development of a proposedlevel. The vertical axis in each chart is the adjusted PAVG (calculated PAVG minus
appropriate adder values); the horizontal axis corresponds to index number asavailable in the ENERGY STAR dataset file.
In data on switches, a set of five products from one manufacturer (index 56-60)
were excluded from analysis. These products were measured to have a PAVG
falling well below all other products in the dataset. Though the presence ofproducts with such low power demands is encouraging, EPA believes that theseproducts are not representative of the bulk of the market given their isolation fromthe rest of the product data available. Accordingly, EPA decided to calculate theproposed Switch base level without these five products factored in.

Figure 1: Adjusted PAVG - ONTs

Figure 2: Adjusted PAVG - IADs

Figure 3: Adjusted PAVG - Routers

Figure 4: Adjusted PAVG - Switches