This paper describes how to detect Honeypots / Honeywalls by using hping to send an ICMP packet containing shellcode and analyzing the response.
You can download it from the following link: https://packetstormsecurity.com/files/download/45179/Honeywalldetection.pdf
Source: https://packetstormsecurity.com/files/45179/Detect-Honeypots-Honeywalls-Using-Hping-Whitepaper.html