Determining Required Bandwidth
Bandwidth is the measure of a network’s capacity or utilization, usually measured in terms of bits per second.
The average estimated bandwidth used by the CB Secure Browser is shared in the table below. Your network design for digital testing should have enough available bandwidth to support these values.
Average Estimated Bandwidth Used
|Students Testing Concurrently||During Testing||During Subsequent Startup|
|1||5–15K bits/second||8K bits/second|
Bandwidth consumed by opening the secure browser and accessing a test for the first time is significantly more than when it is opened and accessed again because a lot of non-test content must be cached when the CB Secure Browser is first accessed.
Whitelisting URLs for the TA and Student Testing Sites
Use a wildcard to whitelist these URLs at the root level because testing servers and satellites may be changed during the school year:
The table below lists network topology recommendations.
Recommended Ratios of Devices to Wireless Access Points
|Testing Device||Ratio of Devices to 802.11g WAP||Ratio of Devices to 802.11n WAP|
|Mix of 802.11g and 802.11n||20||40-50*|
|802.11ac||Under investigation||Under investigation|
*Depends on the mix of wireless cards
Required Ports and Protocols
The table below lists the ports and protocols used by the test delivery system. Ensure that all necessary content filters, firewalls, and proxy servers are open.
Ports and Protocols for Test Delivery System
|80/TCP||HTTP (initial connection only)|
|443/TCP||HTTPS (secure connection)|
Configuring for Certificate Revocations
AIR's servers present certificates to the clients. To check those certificates for revocation, use a certificate revocation list or an online certificate status protocol.
Certificate Revocation List
To use a certificate revocation list, your firewalls must allow this URL: http://crl.verisign.com/
Online Certificate Status Protocol (OCSP)
To use the OCSP, your firewalls must allow the domain names listed below. These patterned URLs are preferred because they are more robust:
If necessary, you can use fully qualified URLs instead:
AIR System Requirements
Covers basic technology requirements for online testing using American Institutes for Research’s (AIR) systems in 2018–2019.
AIR Technical Specifications Manual for Technology Coordinators
Provides hardware, software, and network configurations for running various American Institutes for Research (AIR) testing applications.