Welch Allyn Acuity Network installation Best practices
ii Welch Allyn Network installation © 2014 Welch Allyn. All rights are reserved. To support the intended use of the product described in this publication, the purchaser of the product is permitted to copy this publication, for internal distribution only, from the media provided by Welch Allyn.
iii Contents 1 - Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Welch Allyn Acuity overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 - Acuity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Implementation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Best practices . . . . . . . . . . . . . . . .
iv Contents Welch Allyn Network installation
1 Introduction Welch Allyn Acuity overview Welch Allyn connected workstations, servers and patient monitors utilize standards based communications protocols including, but not limited to, 802.3 for wired Ethernet and 802.11a/b/g for wireless. This guide specifies the requirements and recommendations needed to successfully complete and maintain a Welch Allyn patient monitoring system in your wireless or wired network.
2 Introduction Welch Allyn Network installation
2 Acuity Implementation Welch Allyn has split the best practices into two groupings to bring transparency in making the changes necessary for success. Some items that are included in an individual group may only function correctly if corresponding changes are made in one or both groups. This inter-dependence makes implementation a company-wide undertaking.
4 Acuity Welch Allyn Network installation LAN/WLAN requirements Each of the following tables reflects a different equipment manufacturer.
Best practices Acuity Aruba LAN/WLAN requirements Best practice Affected types Without best practice Bandwidth1 7% Proportional Bandwidth allocation for APs and Wireless Welch Allyn virtual APs/Packet-Shaping. Increased probability of dropped patient data packets on busy wireless networks. Certificates For out of box operation use Welch Allyn certificates and Wired, wireless Welch Allyn will be unable to debug system issues RADIUS Servers. such as monitors unable to connect to Acuity.
6 Acuity Welch Allyn Network installation Best practice Affected types Without best practice Signal strength First wireless signal: RSSI Value -65dBm for (802.11a APs set to 25mW). Second wireless signal: RSSI Value -70dBm for (802.11a APs set to 25mW). Wireless Dropped packets and loss of connectivity due to poor wireless coverage.
Best practices Acuity Cisco LAN/WLAN requirements Best practice Affected types Without best practice Authentication/Encryption WPA2-PSK- AES Only Wireless Other encryption methods not supported. No connectivity. Data rates • a band -- 6Mbps required Wireless Vital signs monitors will not connect. Interference Signal to Noise Ratio (SNR) 15dB Wireless High noise level causes dropped packets. Jitter Packet-to-Packet jitter shall be 400ms.
8 Acuity Welch Allyn Network installation Best practice Affected types Without best practice Connection speed All Acuity systems must be connected to the network using the same Ethernet speed. Wired Dropped packets, data loss. UDP broadcast forwarding Allow UDP broadcasts on ports 7711-7720 from Welch Allyn VLAN to the Acuity Central station. Wired Connections cannot be established. Wired connection Interconnects between all switches and all Cisco WLAN controllers with gigabit Ethernet.
Best practices Acuity 9 WLAN Controller requirements Welch Allyn has identified the following requirements specific to a network and Acuity implementation. While many of these settings involve changes to the controllers themselves, some may involve the wired infrastructure. Each of the following tables reflects a different equipment manufacturer.
10 Acuity Welch Allyn Network installation Aruba controller requirements Best practice Affected types Without best practice Advanced Radio Management (ARM) settings: • Power save aware scan = enabled. • VOIP aware = enabled • Scan interval = 180 seconds1 Wireless APs perform ARM scanning at the time when PSP clients are scheduled to send data, resulting in lost data. Authentication/Encryption EAP-TLS, WPA2-PSK Wireless Other encryption methods not supported. No connectivity.
Best practices Best practice Acuity 11 Affected types Without best practice Wireless Security Use the following ACL for Welch Allyn patient monitors: • IP access-list session WelchAllyn_ACL • any host 255.255.255.
12 Acuity Welch Allyn Network installation Cisco controller requirements Best practice Affected types Without best practice Channel advertisement Advertise 802.11h capability (Broadcast SSID). Wireless Decreased number of 802.11a channels available. If APs are on channels that require 802.11h capability, they will not be available to patient monitors, resulting in RF coverage holes. Channel Switch Announcement (CSA) Disable. Wireless When CSA is enabled, data loss when changing channels may occur.
Best practices Acuity Best practice Affected types Without best practice SSID/WLAN settings Security: • Layer 2 Security = WPA+WPA2 Wireless Loss of connection and data.
14 Acuity Welch Allyn Network installation Best practice Affected types Without best practice WLAN Optimization Cisco recommends the following: • Controller CPU utilization <50% • Radio channel utilization <33% • Number of clients per AP 25 • Controller memory utilization <70% • Average RSSI of all clients -67 dBm • AP Received packet error rate <10%. Hardware, wireless When network performance is outside recommended parameters, potential loss or corruption of data.
