Recommended practices

Last Updated : Oct 30, 2026 |
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General Considerations

Although bandwidth is not limited by the number of VLANs configured, all traffic—regardless of VLAN segmentation—shares the physical constraints of the underlying link, in this case 1 Gbps ports. Excessive VLAN configuration can lead to unmanaged traffic that may exceed link capacity if not properly planned, resulting in saturation, degraded performance, and unpredictable network behavior.
Caution:
Bridge name must be unique. Do NOT assign the same name to multiple bridges.

VLAN Design & Segmentation

Use separate VLANs for:
  • Management traffic (e.g., servers, switches, application management traffic)
  • VoIP traffic (e.g., IP phones, voice gateways, Avaya application traffic).
Avoid placing all VLANs on a single physical adapter (server and switch side). Instead, separate high-traffic VLANs using dedicated links for load spreading when possible.
Enable 802.1Q Trunking
  • Use IEEE 802.1Q to tag VLAN traffic.
  • Ensure matching trunk configurations on both ends (Customer Data switches/routers- ASP 130 servers).
Limit Allowed VLANs
  • Only allow necessary VLANs on the trunk.
  • Allocate 1–5 VLANs max per dedicated 1 Gbps port & 1-10 VLANs max per dedicated 10/25 Gbps port, to ensure optimal performance and manageability.

Apply Quality of Service (QoS)

Prioritize time-sensitive traffic like VoIP or video:
  • Use DSCP EF (Expedited Forwarding) or 802.1p CoS/PCP = 5 or above marking.
  • Follow each Avaya Application best practices when setting QoS.
Implement traffic shaping or prioritization as needed to prevent congestion (e.g., LLQ or priority queues).
Ensure low latency (<150 ms), low jitter (<30 ms), and minimal packet loss (<1%) for VoIP traffic.

Bandwidth Monitoring & Capacity Planning

(Customer Network) Continuously monitor trunk port utilization, using 3rd party NMS tools (not provided by Avaya) such as: PRTG, LibreNMS, NetFlow/sFLOW, ntopng, SolarWinds etc.
Estimate bandwidth usage (consult with each Avaya application documentation):
  • VoIP (audio only):
    • G.729 (low bandwidth): ~8–24 Kbps per call
    • G.711 (standard quality): ~80–100 Kbps per call
    • G.722 / Opus (wideband/high-fidelity): ~64–128 Kbps per call
  • VoIP with video:
    • 480p (SD): ~500 Kbps – 1 Mbps
    • 720p (HD): ~1 – 1.5 Mbps
    • 1080p (Full HD): ~1.5 – 3 Mbps
    • 4K (UHD): ~4 – 8 Mbps
  • VoIP with Audio, Video, and Collaboration
    Screen sharing or document collaboration typically adds:
    • 150 – 500 Kbps (static content)
    • 1 – 2 Mbps (dynamic screen sharing with motion/video)
Management traffic: Typically low, with occasional spikes during remote sessions, firmware updates, or backups.
Maintain average trunk utilization below 80% to avoid congestion and preserve voice/video quality.

Regularly Audit Traffic Flows

  • Verify expected inter-VLAN routing behavior and enforce separation between management and VoIP VLANs.
  • Review firewall/ACL rules to minimize unnecessary traffic between VLANs.

Warning Signs of Overuse or Saturation

Symptom
Possible Cause
Slow network performance
Aggregate traffic exceeding 1 Gbps
High latency, jitter, VoIP/video struggling
Network congestion
Dropped packets
Buffer overflow from oversubscription
Dropped VoIP calls or registration failures
QoS misconfiguration or bandwidth saturation
Excessive broadcast/multicast
Poorly segmented or unmanaged VLANs
Sustained port utilization > 80%
Risk of saturation during peak times
Frequent re-transmissions
Collisions or congestion-induced packet loss
SNMP/monitoring alerts on CPU or interface load
Potential network congestion or broadcast storm