Network Recommendations and Bandwidth

This topic provides a summary of how the network environment affects voice and video call quality. Many factors, including network quality and bandwidth, firewalls, host and device configurations, contribute to the quality of real-time media provided by Virtual Care Solution, which includes audio and video.

Network Quality

The quality of real-time media over IP is significantly affected by the quality of the underlying network connectivity, but especially by the amount of:

  • Latency - The time it takes to get an IP packet from point A to point B on the network. Latency is measured as one-way or round-trip time (RTT).
  • Packet loss - A percentage of packets that are lost in a specific window of time. Packet loss directly affects audio quality. Small, individual lost packets have almost no impact. However, back-to-back burst losses cause complete audio disruption.
  • Inter-packet arrival jitter (also known as "jitter") - The average change in delay between successive packets. The Virtual Care Solution utilizes a video service that can adapt to some levels of jitter through buffering. Only when the jitter exceeds the buffering, will a participant notice the negative effects.

Network Bandwidth

Ensure that network configuration supports the bandwidth required by concurrent Virtual Care Solution video sessions, in addition to other business applications. Testing the end-to-end network path for bandwidth bottlenecks is critical to the successful deployment of the Virtual Care Solution.

The table below contains the bandwidth requirements for the Virtual Care Solution utilizing Azure Communications.

Bandwidth Scenarios
40 Kbps Peer-to-peer audio calling
500 Kbps Peer-to-peer quality video calling 360 pixels at 30 FPS
1.2 Mbps Peer-to-peer HD-quality video calling with a resolution of HD 720 pixels at 30 FPS
1.5 Mbps Peer-to-peer HD-quality video calling with resolution of HD 1080 pixels at 30 FPS

Firewall Configuration

Virtual Care Solution's video communication connections require internet connectivity to specific ports and IP addresses to deliver high-quality multimedia experiences. Without access to these ports and IP addresses, the Virtual Care Solution can still work. However, optimal experience occurs when the recommended ports and IP ranges are open.

The following are specific to the current video provider for Virtual Care Solution, Azure Communications.

Category IP ranges or FQDN Ports
Virtual Care Solution traffic *.dhp.hillrom.com TCP port 443
Media traffic Refer to Microsoft's full range of Azure public cloud IP addresses. UDP 3478 through 3481, TCP ports 443
Signaling, telemetry, registration *.skype.com, *.microsoft.com, *.azure.net, *.azureedge.net, *.office.com, *.trouter.io TCP 443, 80

Network optimization

The following optimizations are optional and are not required for the Virtual Care Solution. The guidance provided below are considerations for optimizing a network with Virtual Care Solution if network limitations exist. Further optimization might be required if the following are true:

  • Virtual Care Solution video runs slowly (this may be due to insufficient bandwidth).
  • Calls keep dropping. Dropped calls might be caused by firewall or proxy blockers.
  • Calls have static and cut out, or voices sound robotic. These issues might be caused by jitter or packet loss.
Network optimization task Details
Maintain session persistence Make sure the firewall settings do not change the mapped network address translation (NAT) addresses or ports for UDP.
Validate NAT pool size

Validate the NAT pool size required for user connectivity. When multiple users and devices access the Virtual Care Solution by using NAT or port address translation, ensure that the devices hidden behind each publicly routable IP address don't exceed the supported number. Ensure that adequate public IP addresses are assigned to the NAT pools to prevent port exhaustion. Port exhaustion contributes to internal users and devices being unable to connect to a Virtual Care Solution video meeting.

Refer to this NAT support with Office 365 article for additional information.
Intrusion detection and prevention

Environments with intrusion detection systems or intrusion prevention system deployed for an extra layer of security for outbound connections, allow Virtual Care Solutionn and Communication Services URLs.

(For example, wss://trouter-azsc-usea-0-a.trouter.skype.com/socket.io/1/websocket)

Configure a split-tunnel VPN Provide an alternate path for the Virtual Care Solution video traffic that bypasses the virtual private network (VPN), commonly known as split-tunnel VPN. Split tunneling means that traffic for the Virtual Care Solution video traffic doesn't go through the VPN but instead goes directly to video endpoint. Bypassing the VPN has a positive impact on media quality, and it reduces load from the VPN devices and the organization's network. Implementation of split-tunneling VPN may require work the VPN vendor. Other reasons bypassing VPN may be a consideration:
  • VPNs are typically not designed or configured to support real-time media.
  • VPNs might not support UDP, which is also required for Virtual Care Solution video communications.
  • VPNs also introduce an extra layer of encryption on top of media traffic that is already encrypted.
  • Connectivity to the Virtual Care Solution video communications might not be efficient because of hair-pinning traffic through a VPN device.
    • Note: Hair-pinning is when a machine on the LAN is able to access another machine on the LAN via the external IP address of the LAN/router (with port forwarding set up on the router to direct requests to the appropriate machine on the LAN).
Implement QoS Use Quality of Service (QoS) to configure packet prioritization. QoS improves call quality and helps monitor and troubleshoot call quality. QoS should be implemented on all segments of a managed network. Even when a network is adequately provisioned for bandwidth, QoS provides risk mitigation if unanticipated network events occur. With QoS, voice traffic is prioritized so that these unanticipated events don't negatively affect quality.
Optimize Wi-Fi

Similar to VPN, Wi-Fi networks aren't necessarily designed or configured to support real-time media. Planning for, or optimizing, a Wi-Fi network to support the Virtual Care Solution is an important consideration for a high-quality deployment. Consider these factors:

  • Implement QoS or Wi-Fi Multimedia to ensure that media traffic is getting prioritized appropriately over the Wi-Fi networks.
  • Plan and optimize the Wi-Fi bands and access point placement. The 2.4-GHz range might provide an adequate experience depending on access point placement, but access points are often affected by other consumer devices that operate in that range. The 5-GHz range is better suited to real-time media because of its dense range, but it requires more access points to get sufficient coverage. Endpoints also need to support that range and be configured to use those bands accordingly.
  • If dual-band Wi-Fi networks are in-use, consider implementing band steering. Band steering is a technique implemented by Wi-Fi vendors to influence dual-band clients to use the 5-GHz range.
  • Access points using the same channel that are too close together can cause signal overlap and unintentionally compete, which results in a degraded user experience. Ensure that access points next to each other are on channels that don't overlap.
Note: Each wireless vendor has its own recommendations for deploying its wireless solution. Consult the Wi-Fi vendor for specific guidance.