Syslog service for dotnet to monitor WIFI and Switch connections and DHCP Requests

SyslogService.cs

/*
   This example Syslog service receives Syslog messages over UDP and publishes them internally using Rx
   to an observable stream `Messages`.
   
   If you point all your Ubiquity (TPLink or other) SysLog messages to a device running this code listening on
   port 514 you can parse the messages and: 

      1) Determine which access point each cell phone is connected to.
      2) Generate an alert every time a new device connects to your network.
      3) Track guests by creating a 'honeypot' SSID like "Google Starbucks" that catches most visitors with Wifi on.
      4) Generate an alert if a device hasn't renewed its DHCP address for some period of time (detect device failures).
   
*/

using System;
using System.Net;
using System.Net.Sockets;
using System.Reactive.Linq;
using System.Reactive.Subjects;
using System.Reactive.Threading.Tasks;

namespace Services.Syslog
{
    public interface ISyslogService
    {
        IObservable<SyslogMessage> GetStream();
    }

    public class SyslogService : ISyslogService
    {
        private readonly Subject<SyslogMessage> messageBus = new Subject<SyslogMessage>();
        private readonly ILogger log;

        public IObservable<SyslogMessage> Messages => messageBus;
        private readonly ICancellationService cancellationService;

        public SyslogService(ICancellationService cancellationService, ILogger log)
        {
            this.cancellationService = cancellationService;
            this.log = log;
        }

        public IObservable<SyslogMessage> GetStream()
        {
            var anyIp = new IPEndPoint(IPAddress.Any, 514);
            var stream = UdpStream(anyIp).Select(Parse);
            return stream;
        }

        private SyslogMessage Parse(UdpReceiveResult result)
        {
            var endpoint = result.RemoteEndPoint;
            var text = System.Text.Encoding.ASCII.GetString(result.Buffer);
            int priority = 8 + 1; // TODO
            var timestamp = DateTime.Now;
            string hostname = result.RemoteEndPoint.ToString();
            return new SyslogMessage(endpoint, priority, timestamp, hostname, text);
        }

        public static IObservable<UdpReceiveResult> UdpStream(IPEndPoint endpoint)
        {
            return Observable.Using(() => new UdpClient(endpoint),
                    udpClient => Observable.Defer(() => udpClient.ReceiveAsync().ToObservable()).Repeat());
        }
    }
    
    public class SyslogMessage
    {
        public SyslogMessage(IPEndPoint endPoint, int priority, DateTime timestamp, string hostname, string message)
        {
            this.EndPoint = endPoint;
            this.Facility = priority/8;
            this.Severity = priority%8;
            this.Timestamp = timestamp;
            this.Hostname = hostname;
            this.Message = message;
        }

        public IPEndPoint EndPoint { get; }

        public int Facility { get; }

        public int Severity { get; }

        public DateTime Timestamp { get; }

        public string Hostname { get; }

        public string Message { get; }

        public override string ToString()
        {
            return
                $"Facility: {Facility} Severity: {Severity} Timestamp: {Timestamp} Hostname:  {Hostname} Message: {Message}";
        }
    }
}