Basic principles of Clear-Com products use of PTP / AES

1. Basic principles

When using AES67 / ST2110-30 digital audio networks they require the following network provisioning.

• High bandwidth, Guaranteed bandwidth to support audio streams, Low network latency and Very low network jitter.

• The use of QoS, IGMP and VLANS to separate the AES67/ ST2110 steams from other data on the network.

• A Ethernet switch fabric made up of enterprise grade switches that support boundary / transparent clock mode

• Ensure Spine / Leaf uplinks are large enough to support all end points on the leaf receiving audio.

 Often for small to medium AES67/ ST2110 networks are easier to implement using layer 2 network

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Each Clear-Com PTP endpoint device (IPA card / Iris panel / IPT transceiver) uses the following protocols.

•  PTP data packets MultiCast - to sync the GM on the network

• AES67 audio data packets Unicast to pass audio between IPA card and the Iris or IPT

• Auto discovery using mDNS of Clear-Com only devices.

• ST2110-30 audio data packets Multicast to pass AES67 audio between

1. AES67 trunk lines between Clear-Com matrices

2. The IPA card and 3^rd party AES67 devices.

How do Clear-Com devices join a Grandmaster (GM) PTP domain?

If an IPA card is set into PTP follower (slave) mode it will sync to the GM (Leader) on the network

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Figure 1: PTPv2 protocol settings

The E-IPA card PTP settings must match the GM PTP profile (domain #, announce interval, sync interval etc.)

 Once the E-IPA card discovers and registers (associates) with any Iris-X panels or IP transceiver on the network it sends the same PTP profile information to the Iris-X / IPT endpoint device (via the AES67 admin address). The Iris / IPT will then join the GM PTP domain and obtain PTP sync.