South Gym Networking Plan

Requirements

• Local network switch for AV control devices
• Network connectivity back to the facility’s core switch for AMX control and audio/video feed routing
• VLAN structure compatible with the existing facility network

Uplink

The South Gym connects to the facility network via a fiber run from the IT room. This provides the uplink for AMX control, SVSi video routing, and VLAN trunking.

Topology: Core Switch (Netgear GSM4248PX) > IT Room Switch (Netgear GSM4230PX) > South Gym Switch (Netgear GSM4248PX). The IT room switch has free SFP ports for the fiber uplink. The trunk carries tagged traffic only (no native VLAN).

LC duplex termination throughout.

The fiber path has three segments:

Segments 1–2 use armored fiber for all exposed runs. Segment 3 uses non-armored fiber – a deliberate choice because armored cable is difficult to position and terminate in a rack. Both cable types are Corning OS2/SMF-28 singlemode and are splice-compatible, though the cable is pre-terminated on spools so no field splicing is needed.

SFP+ transceivers: 10G SFP+ trunks, matching the rest of the building. Third-party/generic SFP+ modules are used, same as existing facility trunks. Specific model TBD during commissioning.

Strand allocation

Junction box (12 strands in, 6 continue):

• 6 strands continue to the AV rack (segment 2)
• 6 strands spare for future use
• Junction box is accessible by removing a drop ceiling tile

AV rack (6 strands):

• 2 strands: AV switch (Netgear M4250)
• 2 strands: IT switch
• 2 strands spare for future use

Fiber is pre-labeled at the factory. As-built documentation showing strand-to-termination mapping will be created after installation.

Post-install fiber validation

No OTDR is available, and none is needed for pre-terminated cable on a short run. Post-install validation steps: (1) confirm 10G link negotiation on both ends, (2) read SFP+ DDM/DOM optical RX power from the M4250 management interface and record as baseline, (3) run iperf3 to verify sustained throughput, (4) monitor switch error counters (CRC, frame errors) over the first few days. Cable attenuation ratings will come from the manufacturer.

Fiber uplink failure analysis

The fiber uplink is a single point of failure for AMX control, SVSi video routing, LP10 network streaming, ClickShare discovery, and rack PC internet access. Per-device behavior if the uplink is lost:

Fallback: A Raspberry Pi running Bitfocus Companion in the South Gym rack provides local control; access via a laptop plugged into the local M4250. Analog audio paths continue working independently of the uplink. See control.md Failure & Fallback section for full details.

Switch

Netgear M4250 PoE+ GSM4248PX (48-port) as the local managed switch. The M4250 supports the facility’s VLAN scheme and has SFP+ slots for the fiber uplink to the IT room.

Why M4250 PoE+ (not PoE++)? PoE+ (802.3at, 30W/port) provides sufficient power for AMX touch panels and SVSi endpoints. PoE++ (802.3bt, 60-90W/port) would add cost for capacity we don’t need – none of the planned PoE devices require more than 30W. Why Netgear M4250? The M4250 is the facility standard – it’s already deployed in the auditorium, atrium, and for digital signage. Using it in the South Gym maintains consistency across the facility for management, sparing, and troubleshooting. It’s a managed switch designed for AV applications, with IGMP snooping, QoS, and VLAN support out of the box.

Engage Controller: All facility M4250s are managed via Netgear Engage Controller, which pushes consistent VLAN, QoS, IGMP snooping, and unregistered multicast filtering settings across every switch automatically. The South Gym M4250 will receive the same configuration as the rest of the facility.

Monitoring: Addressed in control.md – Prometheus via SNMP for switch stats, Uptime Kuma for device pings. Same facility monitoring stack as all other switches.

Firmware updates: SVSi endpoints and RLNKs are updated during commissioning; hardware is mostly discontinued so future updates are unlikely. M4250s are updated periodically via Engage Controller. BLU-100s have not been updated and will only be updated if a compelling reason arises. No formal maintenance window policy.

Security configuration: Same as the rest of the facility M4250s – SSH enabled, admin user with SHA512-encrypted password, SNMP with SHA512 auth and read-only community string restricted by source IP, HTTP/HTTPS on non-default ports (49151/49152). Engage Controller pushes consistent config. See existing switch configs in this repo under Networking/. Unused switch ports (e.g., long-term VX4S ports on VLAN 21) are not administratively shut down – physical access to the rack closet is restricted, so unused port shutdown is not necessary.

IGMP and multicast: The M4250 does not act as an IGMP querier on VLAN 25 – it delegates to the core switch, using the existing facility IGMP settings. Multicast containment (pruning) is managed at the core switch. This is the same architecture used across the rest of the building. With properly configured IGMP snooping, unsubscribed SVSi streams are pruned and do not consume switch bandwidth.

SVSi compatibility: SVSi stream delivery over M4250 switches has been tested and works fine across the rest of the building. The N4321 audio transceiver uses the same IGMP multicast mechanism as SVSi video – it is not AES67 and has no PTP requirements.

Switch port count

~19 copper ports + 1 SFP+ uplink at full build-out. Near-term (before LED wall): ~14 ports. A GSM4248PX (48-port) provides comfortable headroom for future expansion.

Not on M4250: Midas DL16 (rack and portable) are AES50 only – no Ethernet. IT switch has its own fiber uplink. School AP is on a separate network.

Wireless device notes:

• Arylic LP10: WiFi disabled; wired-only on VLAN 5 (SPACnet) to prevent bridging two networks or creating a rogue AP.

• Barco ClickShare: Uses facility WiFi, not its own AP. WiFi band/channel coordination is IT’s responsibility.

• Midas M32R: Ethernet is used for the remote control app. On VLAN 21 (Control), accessible via IT WiFi which broadcasts into the gym space.

• VLAN assignment for Rack PC and ClickShare – both may need to be on SPACnet (VLAN 5) for user device discovery, or split across VLANs with appropriate routing

• Final AMX touch panel count

PoE consumers

This list will be updated as equipment is added. The M4250 PoE+ models provide up to 30W per port (IEEE 802.3at). Total switch PoE budget depends on the model selected.

VLANs

The facility uses a standard VLAN scheme across all AV switches. The M4250 in the South Gym will trunk these VLANs over the fiber uplink. Not all facility VLANs are needed in the gymnasium.

South Gym active VLANs: 1, 5, 21, 25. The trunk port to the core switch should carry at least these four. Other VLANs can be pruned at the trunk or simply left unconfigured on local ports.

Inter-VLAN routing is handled on the IT room switch (not on the M4250). VLAN 21 (Control) can access VLANs 5 (SPACnet) and 25 (SVSi). No ACLs or firewall rules are in place. Trunk latency has not been observed as an issue. This means the remote AMX processor (NX-4200) reaches all South Gym devices on VLAN 21 through the trunk – including the RLNK-915R for power sequencing and the AMX EXB-COM2 for RS-232 control of the ETC Paradigm ACP (both lighting layers). If the fiber uplink is down, the Raspberry Pi running Bitfocus Companion in the South Gym rack provides local control as a fallback.

BSS BLU-100 control protocol: HiQnet uses IANA port 3804 (TCP for reliable control, UDP for discovery datagrams). Discovery uses IP broadcast, not multicast – DiscoInfo messages are network-broadcast, so IGMP snooping on VLAN 21 does not need any special configuration for HiQnet. This is distinct from VLAN 25 (SVSi), which does use IGMP multicast. See HiQnet Third Party Programmer’s Guide sections 4.5.1–4.5.2 and 4.1.6.

AMX RS-232 bridge: The remote AMX NX-4200 processor sends RS-232 commands to the ETC Paradigm ACP (PSAP protocol, controls both gymnasium and event lighting layers) via an AMX EXB-COM2 ICSLan serial expansion module (FG2100-22) in the South Gym rack, on VLAN 21 (Control).

IT Network

The IT team runs on separate hardware from the AV network. Our responsibilities:

• Pull the fiber and all cabling (we handle all fiber-related work)
• Install their switch in our rack (we provide the rack space and physical install)
• Pull cable for their wireless access point (Cat 6A, matching all other new data runs)

IT’s responsibilities:

• Configure their switch
• Install and configure their AP on the junction box we provide

School Network

The school has an existing AP in the room with an existing cable drop. We need to provide:

• Conduit run to the new AP mounting location
• Junction box for AP mounting
• Attempt to preserve the existing cable and extend it to the new box (depends on available slack) – the rest of the building uses Cat 5e, so the existing school AP cable is likely 5e (adequate for PoE at these distances)
• TBD: Coordinate with the school division on AP cabling requirements

AV Rack

See Rack Plan for rack layout, power budget, and location details.

Patch panels

4U allocation in the rack (cross-reference: rack.md U1–4):

• U1: Fiber patch panel (1U)
• U2–3: Neat patch (2U) – clean cable management between patch panels and switches
• U4: Copper patch panel (1U, 24-port Cat 6A)

Specific panel models TBD.

Network Drops

Cat 6A drops required within the South Gym. This list will be updated as equipment is added or removed.

In-rack devices share a short patch to the M4250 and don’t need dedicated cable runs.

• TBD: Wall plate locations and quantities
• TBD: Additional drops as equipment list is finalized

Considerations

• Run sufficient Category 6A cabling within the South Gym – even if not all ports are used initially, pulling cable during renovation is far cheaper than retrofitting later
• LED wall data cabling (long-term): Cat 6A – overkill for the VX4S panel protocol but matches everything else in the build and is guaranteed to work. Cable count TBD once LED wall configuration is finalized.

Commissioning Documentation

The following tables will be completed during commissioning and serve as the as-built network documentation.

IP Address Assignments

Switch Port Map

• Patch panel port assignments to be completed during commissioning
• Actual switch port numbers may change — this is a logical mapping

Patch Cable Labeling

• TBD: Labeling standard (Brady, P-touch, heat-shrink) and naming convention. (Cross-reference: rack.md cable labeling question.)

Configuration Backup

• Export M4250 startup-config after commissioning and store in this repo under Networking/South Gym Switch/

Open Questions

VLAN Design & Switch Configuration

• What STP mode is in use facility-wide (STP, RSTP, MSTP)? Should edge ports (SVSi endpoints, BLU-100, touch panels) be configured as edge/portfast to avoid 30-second STP delays on link-up? Is BPDU guard or root guard needed on any ports? Using M4250 defaults. Worth future consideration but hasn’t historically been a problem.

Device Discovery Protocols

• Multiple devices rely on mDNS/Bonjour and SSDP for user device discovery. These protocols do not cross VLAN boundaries without a helper/proxy (e.g., Avahi reflector, mDNS gateway). The existing facility switches have no bonjour enable. How will the LP10 (VLAN 5, AirPlay 2/Google Cast/Spotify Connect) and ClickShare (VLAN TBD, AirPlay/Miracast) become discoverable to user devices on IT WiFi (likely a different VLAN)? A dedicated “South Gym AV” WiFi network on the same VLAN as these devices would provide native mDNS/Bonjour/SSDP discovery without cross-VLAN helpers. Details TBD — VLAN assignment, AP hardware, SSID/security, and whether this is an additional AP or a repurpose of an existing one.
• If the ClickShare is on a different VLAN than user devices, will native AirPlay/Miracast (which relies on mDNS/Bonjour) fail? The video plan explicitly lists ClickShare as the wireless presentation path for teachers, presenters, and wedding families – this is a core use case. Addressed by the “South Gym AV” WiFi network — if ClickShare and user devices are on the same VLAN, AirPlay/Miracast discovery works natively.

Physical Layer & Cabling

• What are the Cat 6A run distances from the rack to: the back-wall N1115-WP wall-plate encoder, the ceiling-mounted NMX-DEC-N1222A decoder, the M32R floor drop(s), and AMX touch panel location(s)? Are all runs within the 100-meter Cat 6A maximum? PoE performance degrades over distance. (Cross-reference: electrical.md conduit path questions.) All runs expected to be well under 100m, but exact distances need to be measured on-site.

SVSi / AV-over-IP

• What is the typical bandwidth of an MPC-compressed 1080p60 stream (typically 200-400 Mbps)? How many simultaneous SVSi streams could be active at once (2 encoders local + 1 overflow from auditorium, 2 decoders subscribing)? Does the 1 Gbps fiber uplink have sufficient headroom for worst-case multicast load plus control traffic plus rack PC internet traffic? Bandwidth is likely higher than the 200-400 Mbps estimate — need to verify from encoder specs. The fiber uplink is 10G SFP+, so headroom should be substantial.

Wireless & IoT

• The LP10 has Bluetooth 5.2 with a 15m range rating. In a gymnasium with metal ceiling structure, what is the realistic Bluetooth range from the rack closet to a user in the gym? Is the rack closet door solid or does it attenuate Bluetooth? If range is insufficient, the Bluetooth fallback does not actually work. Range may be poor through the closet door/walls — needs real-world testing after install. WiFi-based playback (AirPlay 2, Google Cast, Spotify Connect) is likely the more reliable path. Bluetooth is a nice-to-have, not a guaranteed fallback.

M32R Floor Drop

• Is the M32R floor drop a single Cat 6A jack, or does it need multiple jacks (one for Ethernet, one for AES50 if carried over structured cabling)? AES50 uses a proprietary protocol that is not standard Ethernet – if AES50 is expected to traverse a patch panel and switch, it will not work because AES50 is not routable.
• Does the floor drop location need to support the M32R cart on either side of the room, or is a single fixed drop sufficient? If two locations, are two floor drops needed? (audio.md raises this question.)
• Is the floor drop a flush floor box, and does it need to be rated for gymnasium floor traffic (rolling carts, ball impacts)?

LED Wall Data Cabling (Long-Term)

• Should cables be pulled into the LED wall conduit now (risk of damage during construction), or should conduit be left empty for future pull? What is the maximum distance from the rack to each candidate LED wall location (standard 100m limit applies)? Deferred — to be determined with the LED wall manufacturer.

Network Monitoring & Operations

• The M4250 PoE model selection (24 vs. 48 port) depends on the total PoE budget. Known PoE consumers total ~33W (decoder + encoder), plus TBD touch panel(s) at 12-25W each. Has the selected model’s PoE budget been verified as sufficient with headroom for future PoE devices? Equipment list is nearly finalized. PoE budget is overkill — the GSM4248PX provides 960W against an estimated total PoE draw well under 100W. Verify once final device list is locked.