It's a Zero Config IP address. Most likely a host with zero config enabled, pretty much all Windows by default, was unable to get an IP from DHCP.
On 10/28/2015 9:04 AM, Timothy Murphy wrote:
Why does "arp -a" show IP address 169.254.192.123 on my 192.168.2.0 home network? I recall seeing this IP address somewhere, but don't remember where.