Industry

Internet Service Provision
 Tuesday, June 11, 2002

Smart networks are a Layer 8 problem.

6:29:45 PM #
categories: Industry, Layer 8

Concentrating on the Red Herring

On Saturday Boingo Boingo pointed out an article called "Delivering Differentiated Services through Deep Content Inspection" that describes a method for implementing content-based billing. The author correctly notes that "[t]his can only be achieved in a network equipped with a classification processor that performs layer 7 content inspection and classification." However, this inspection depends on being able to read the packet. TLS/SSL, and, more importantly, ssh and IPsec, thoroughly defeat inspection of the packets except by the end-points.

Encryption is not widely deployed as it is, mostly because of usability issues. I would expect that if a telco were to adopt content-based billing, that encrypted traffic would be billed at the highest cost, because it would be impossible to distinguish between it and other traffic — thus leading to even slower adoption of encryption.

But more importantly, content-based billing is a red herring. While it may seem to offer the telco the ability to extract rents from network traffic it will act instead to reduce the amount of traffic, in addition to increasing the deployment and equipment costs.

For more detailed information on inspecting content, see snort.org or any number of network analysis sites. The exact method describes in the article is used now by firewalls and intrusion detection devices to filter out malevolent traffic.

6:20:38 PM # Google It!
categories: Industry