Application based routing has previously been restricted to use only the IP header fields to classify a flow into a user defined application.  A deep packet inspection module is now available and extends application identification for traffic destined for the WAN network.

The ICMP protocol has a type of messages used to handle problematic situations in a network, like for example destination unreachable, packet's Time To Live exceeded, and others. They all contain the "original datagram" field which represents the leading octets of the datagram to which the ICMP message is a response. The original datagram consists of the IP header + at least 64 bits of the data.