What Is Deep Packet Inspection (DPI)?

 

Deep packet inspection (DPI) enables network operators and service providers to go well beyond standard network monitoring and error reporting, based on just the header portion of a packet. As traffic passes an inspection point in the network, DPI can monitor the actual content of those network traffic packets: headers, data protocol structures, as well as the actual payload of the message. This allows finer visibility and control than that based only on header information.

 

Current Uses of DPI

 

DPI is currently being used by the enterprise, service providers and governments in a wide range of applications. Some of the primary uses include:

Traffic Monitoring DPI evolved from earlier methods of traffic monitoring and is still used to help network managers know which applications are using bandwidth on their networks.

Traffic Management and QoS DPI enables traffic throttling, blocking at a flow or application level. This has become especially important as bandwidth-hungry, priority-packet multimedia usage has skyrocketed, mainly in the form of Voice over IP (VoIP) and video/audio over IP. DPI is now used to assure the quality of service (QoS) for different applications on an application, service, or customer basis.

Security and Encryption DPI is playing a growing role in security applications. It is being used to fight spam, phishing, distributed denial of service (DDoS) attacks, botnets, viruses, and other threats.

Lawful intercept DPI enables operators to meet the requirements of the Communications Assistance for Law Enforcement Act (CALEA) and it international equivalents to ensure that security services can use equipment for surveillance, in particular for VoIP traffic.

Revenue Generating Applications The next logical step for DPI, once a service provider has it in place, is to use the investment to generate income. This packet-level knowledge can enable tiered QoS offerings, customized pricing and billing, reliable event-based billing, targeted advertising, ad tracking, parental control or enterprise content blocking, and digital rights management. Some of these applications raise public concern with privacy, censorship, and a reduction in the openness of the public Internet; vendors and service providers acknowledge this and are aware that development of services must occur in a proper, legal manner.

 

Packet Processing Demands of DPI

 

DPI applications are required to access packets, review them, and make a decision on what to do with that data, all at a speed that does not interrupt or delay the data flow of legitimate data traffic. This is especially crucial with voice and video traffic. In order to accomplish this, it requires advanced packet processing. The industry has turned to multicore processors such as those from Cavium and RMI. Multicore network processors are ideal for handling DPI data processing demands:

• Optimized for packet handling
• Reduced instruction set
• Real Time or Linux operating system
• Hardware accelerators

 

How Interphase Fits in the DPI Solution

 

Interphase offers a family of wire-speed packet processing cards for the delivery of broadband services in the 3G Wireless, Voice Over IP, and IMS network infrastructure. These iSPAN cards are extremely versatile and provide the processing power necessary for migrating to next-generation infrastructures and converged networks. These iSPAN cards are ideal to spec into DPI applications:

• Based on Cavium Networks high-performance OCTEON Plus packet processors that provide per-core hardware acceleration for packet processing and security
• Integrated co-processors for packet I/O, compression/decompression, encryption/decryption, IDS, and anti-virus
• Support choice of 4 to 16 cores with NSP or SCP options
• Offer a range of network interfaces
• Available in both AdvancedMC (AMC), full- and mid-size, and PCI-x form factors
• Available off-the-shelf or customized to exact specifications

 

Extensive third-party packet processing software toolkits are available for these multicore iSPAN cards so they can be easily integrated into DPI solution platforms for these uses and many more:

• TCP/IP off load
• Wire-speed IPSE acceleration
• Policy Management and Routing
• SRTP Off-load
• On board RTP/RTCP processing
• GTP-u protocol support for Wireless network applications

For more information on specific standard or customized iSPAN multicore cards:

• Download the summary multicore packet processor product sheet
• Contact Interphase Global Sales for answers to your more detailed questions
• Further reading: AdvancedTCA: The Perfect Fit for Deep Packet Inspection (DPI)