NetworkService/DeviceInfo.cs

using System.Net;
using System.Text;

namespace NWService
{
    public class DeviceInfo
    {
        private IPAddress ipAddr;
        private byte[] macAddr;

        public DeviceInfo(IPAddress iPAddress, byte[] macAddressBytes)
        {
            this.ipAddr = iPAddress;
            this.macAddr = macAddressBytes;
        }

        public IPAddress GetIPAddress()
        {
            return ipAddr;
        }

        public string GetMacAddress(char separate = ':')
        {
            StringBuilder sb = new StringBuilder(18);
            foreach (byte b in this.macAddr) {
                if (sb.Length > 0)
                {
                    sb.Append(separate);
                }
                sb.Append(string.Format("{0:X2}", b));
            }

            return sb.ToString();
        }
    }
}