Skip to content
Pricing RU Sign In
RU

Port 47808 — BACnet/IP

By · Updated
Key idea:

UDP/47808 (hex 0xBAC0) — BACnet/IP, the building-automation protocol: HVAC, lighting, access control, elevator control. Standard ANSI/ASHRAE 135. Open discovery via Who-Is broadcast on 47808. Never expose to the internet (no auth). Enterprises use BACnet gateways with TLS, or an MQTT/OPC UA bridge.

Below: details, example, related, FAQ.

Try it now — free →

Details

  • Protocol: BACnet/IP (over UDP), also BACnet/MSTP (RS485) + BACnet Secure Connect (BACnet/SC, new)
  • Who-Is / I-Am discovery on UDP/47808 broadcast
  • Objects: Device, Analog Input, Binary Output, Schedule, Notification
  • BACnet/SC (2020+) — TLS 1.3, WebSocket, fixes the auth gap
  • Nmap: -sU -p 47808 --script bacnet-info

Example

# Discovery
$ nmap -sU -p 47808 --script bacnet-info 10.0.0.0/24

# Python bacpypes Who-Is
from bacpypes.app import BIPSimpleApplication
from bacpypes.local.device import LocalDeviceObject
app = BIPSimpleApplication(LocalDeviceObject(...), '10.0.0.5')
app.who_is(1, 999, Address('10.0.0.255'))

Related

Related guides

ICMP PingHost availability and latency
Port ScannerOpen TCP port detection
LatencyResponse time in milliseconds
Packet LossPercentage of dropped packets

Why teams trust us

ICMP+TCP
check protocols
14
key ports scanned
<2s
result
3
regions

How it works

1

Enter IP or domain

2

ICMP packets sent

3

Latency & packet loss shown

How Do Ping and Port Scanning Work?

Ping sends ICMP packets to a host and measures response time. Port scanning checks which TCP ports are open and accepting connections — helping diagnose serviceavailability issues.

Configurable Ping

Choose packet count (3, 4, 6, 10). Stats: min/avg/max latency and packet loss.

Common Port Scanner

Check 14 key ports: HTTP, HTTPS, SSH, FTP, SMTP, MySQL, PostgreSQL, and more.

Cloud-Based Check

Testing from our server — see site availability from outside, not just your local network.

Uptime Monitoring

Need constant monitoring? Create a monitor — checks every minute with notifications.

Who uses this

DevOps

availability diagnosis

Network engineers

TCP port scanning

Developers

connection debugging

SRE

basic health check

Common Mistakes

❌
ICMP blocked = server is downMany servers block ICMP. Ping fails but site works — check ports instead.
❌
High ping = server problemLatency depends on geography. 150ms between continents is normal, not an error.
❌
Closed ports — cause for alarmClosed ports of unused services are good. Unnecessary open ports are a risk.
❌
One check = sufficientNetworks are unstable. A single timeout ≠ a problem. Check multiple times or set up monitoring.

Best Practices

✓
Combine ping and port checksPing shows host availability, ports show specific service availability. Use both.
✓
Check from different locationsThe problem may be local. A cloud test shows the real picture.
✓
Close unused portsEvery open port is a potential attack vector. Keep only necessary ports open.
✓
Set up monitoringManual checks do not scale. Set up automated monitoring with notifications.

Get more with a free account

Ping check history, host availability monitoring and downtime alerts.

Sign up free

Related tools

TracerouteDNS LookupWHOISSSL Check

Frequently Asked Questions

BACnet vs Modbus in a building?

BACnet for HVAC + lighting + access control. Modbus for generic PLC. Often BACnet on top + Modbus on the field level.

Exposed 47808?

Never on the public internet. Even internal — segment the VLAN, block via ACL.

Is BACnet/SC ready?

ANSI/ASHRAE 135-2020 addendum; vendor support — Carrier, Siemens in progress. Consider it for new projects.

Start monitoring for free

Sign up and get access to API, monitoring and notifications

Create Account API Documentation