Knowledgebase: dLive
gigaACE and DX networking, VLANs, and fibre optics
Posted by Nicola Beretta, Last modified by Jack Kenyon on 09 March 2020 01:05 PM


gigaACE is a Gigabit Ethernet point-to-point connection (1000BASE-T, IEEE 802.3ab), Layer 2 compliant.

Layer 2 network switches and media converters can be used, provided they support Gigabit Ethernet (1000BASE-T) connections.

DX Expanders

DX links are Fast Ethernet point-to-point connections (100BASE-TX, IEEE 802.3u), Layer 2 compliant.

Layer 2 network switches and media converters can be used, provided they support Fast Ethernet (100Base-TX) connections.

General rules

Typical applications include conversion to fibre optic for longer cable runs between MixRack, Surface or Expanders, or integration within an existing network infrastructure in a building.

Layer 2.5 and higher protocols including Spanning Tree, Tagged Egress Packets, and Broadcast Storm Protection can cause interruption to audio data or audible clicks.
Smart / managed switches may allow turning off Layer 3 or 4 functions, but as a general rule we recommend using Layer 2 devices only.

Note that no other network device should be plugged into a switch carrying gigaACE or DX Expander audio unless a dedicated VLAN is set up.

Parallel connection of multiple DX Expanders on a switch is not possible.

When using an Ethernet switch or media converter, we suggest you check for errors and test for functionality and reliability before putting your system into service.


It takes some trial and error to configure a VLAN for use with DX or gigaACE, and the actual configuration depends on the specific switch in use. In our tests, we also found that many switches do not handle the gigaACE / DX packets with the time accuracy our clock requires, particularly over trunk lines and SFP modules, resulting in sync errors and in some cases, audible glitches. Thus use of VLANs is not officially supported and the notes below are given as a guideline only.

One VLAN is needed for each point-to-point connection i.e. you cannot have more than two DX / gigaACE devices on the same VLAN.
No other traffic should be present on this VLAN.

The ports should be forced to 100Mbps (Fast Ethernet) for DX / ACE / dSNAKE, or Gigabit Ethernet for gigaACE - we had mixed experiences with auto-negotiating ports. The ports need full 100Mbps / 1000Mbps bandwidth. This means that, in order to have a gigaACE VLAN on a switch, the trunk between switches must be higher than Gigabit (10 Gigabit recommended).

ALL Layer 2.5 and higher protocols must be disabled, as mentioned above. Essentially any packet on the VLAN other than audio transport is likely to cause audible glitches. The VLAN should be fully transparent to Layer 2 traffic, with no extra packet.

Also note that dLive firmware prior to V1.8 had gigaACE fixed to VLAN 1, which would often conflict with the management VLAN on some switches. The VLAN tag was been removed in V1.8 allowing user tagging of gigaACE traffic.

Fibre optics

Most standard Cat5 to F.O. converters will work, provided they support the required connection type / speed (see above).

We have tested two rugged, professional systems, ideal for live use:

Fiberfox FCM-GMC Ethernet Gigabit Medienkonverter

Manufacturer: Connex GmbH

Description: Rugged modular converter with built-in power supply and optional rack mounting kit

Features: 10/100/1000BASE compliant with Auto Negotiation, multimode (<2km) or single mode (<30km) models available

Works with: gigaACE, DX Expanders (TBC), dSNAKE

Cat5 connector: EtherCon

Fibre connector: Fiberfox EBC (expanded beam) or Neutrik OpticalCon Duo depending on model

Also available from Connex is the full range of Fiberfox cables and products

MCM1000 Fiber-Cat5e Media Converter 

Manufacturer: Whirlwind

Description: 1U rack converter

Features: Gigabit Ethernet, multimode or single mode models available

Works with: gigaACE

Cat5 connector: 1x or 2x EtherCon depending on model

Fibre connector: Neutrik OpticalCon Duo or OpticalCon Quad depending on model


Smart / managed switch - a switch with features that can be configured to perform network management functions.
These functions can be as simple as setting the link speed of a port or disabling it entirely, or more complex like limiting bandwidth or grouping devices into VLANs.

Layer 2 Ethernet device – a Layer 2 device is hardware based. It operates at the Data Link layer, which handles physical addressing.
It looks only at the MAC address and LLC portions of an Ethernet frame, and forwards data packets accordingly.

Layer 3 Ethernet device – these devices operate at the Network Layer, which provides network path determination and logical addressing functions.
In most cases, this means that Layer 3 switches handle packets based on their IP address.
Common functions of a Layer 3 or 4 switch (also referred to as multilayer switch) include QoS and IP multicast.

keywords: fibre fiber network switch dLive DX gigaACE Ethernet