Tecknow Magazine

Services and protocols are distinct concepts although they are frequently  confused. The distinction  is so imprortant however that I emphasize it again  in this article.
A  service is a set of primitive operations that  a layer provides to the layer above it .The service defines  what  operations  the layer is prepared to perform  on behalf of its users , but it says nothing  at all  about how these operations  are implemented A service relates to an interface between two layer, with the lower layer  being the service  user.
A protocol in contrast is a set …

Cosmology studies of the universe at large and its size, its shape and its evolution. Seeking to grasp the universe the mind of the cosmologist has  to wander often at distances as great as 10 billion light years  and over time  as long as 10 billion years or  longer.
Until the early part of this century  astronomers thought the universe to be much smaller.
They thought that the in the universe the furthest stars at the edge of our galaxy were about 30,000 light years away and that there  was nothing but …

No matter what version of Linux you use,the piece of code common to all is the Linux kernel. Although the  kernel can be modified  to include support for the features you want. Every  linux kernel  can offer the following features.
1) Multiuser
Not only can you have many user accounts available on a linux system, you  can also have multiple  users  logged in and working on the system at the same time. Users can have  their own environment arranged  the way they want :
their own home directory for storing files and their …