Archive News

April, 2003

FEATURE ARTICLE: (COMMSDESIGN) The 7 Faces of The OSI Networking Model – Part 2

The Seven Faces of the OSI Network Model: Part 2

John Drabik, Arcturus Networks

The Open System Interconnect (OSI) network model, referred to by many as simply a stack, is in fact a well-designed, layered architecture for efficient intersystem and intrasystem communications. In this two-part series, we provide a new view of the stack, showing how the layers are interconnected, and protocol services available at each level.

In Part 1 of this article, we provided an overview of the stack and delved into details on Layers 5 to 7, general concepts of abstraction, syntax, translation, programming interfaces, and functions associated with the model. Now, we’ll further the discussion by looking at Layers 1 to 4 as well as at some non-layer layer items that are important for designers. Let’s start our discussion by looking at Layer 4.

Read the whole article at Commsdesign

FEATURE ARTICLE: (COMMSDESIGN) The 7 Faces of The OSI Networking Model – Part 1

The Seven Faces of the OSI Network Model: Part 1

By John Drabik, Arcturus Networks

For many in the communication industry, the open system interconnect (OSI) network model is a simply a stack. But, designers shouldn’t be so quick to diminish the value that the OSI model provides to the networking sector. While appearing to be simply a stack on the surface, this model is a well-designed, layered architecture for efficient intersystem and intrasystem communication.

In this two-part series, we’ll provide a different view of the OSI model, showing how the layers are interconnected and what protocol services are available at each level. In Part 1, we’ll provide a general overview of OSI and then examine Layers 5 to 7 of the stack. In Part 2, we’ll examine Layers 4 to 1 as well as some non-layer items such as network-aware bootloaders.

Read the whole article at Commsdesign

FEATURE ARTICLE: (HOMETOYS) Creating an Effective VPN Implementation on Embedded Linux

Creating an Effective VPN Implementation on Embedded Linux

an Arcturus Networks White Paper by John Drabik

Anybody who spends time trying to build networking devices, realizes that there are significant development challenges to overcome. Linux-based devices are no exception. Without proper care, projects might have inappropriate code sizes (and are thus not cost effective), poor performance, or interoperability issues.

Nowhere is this more true than in low cost VPNs, which demand strong cryptography support. In this market, price is everything. Users want all of the new features and robustness of Linux, but they want it cheap. Since price is everything, the cost of a second Flash memory can make the difference between product success or failure; adding a hardware crypto engine is even worse. Vendors can be tempted to cut corners: stability, standards compliance, processor independence, and overall code quality can suffer as a result.

Read the whole article at Home Toys