The PPP and OSI protocols share the same physical layer, but PPP distributes the functions of LCP and NCP differently. PPP operates across any DTE/DCE interface. The only requirement imposed by PPP is a duplex circuit, either dedicated or switched, that can operate in either
From Wikipedia, the free encyclopedia. The cisterna magna (or cerebellomedullary cistern) is one of three principal openings in the subarachnoid space between the arachnoid and pia mater layers of the meninges surrounding the brain. The openings are collectively referred to as cisterns.he two other principal cisterns are the pontine cistern located between the pons and the medulla, and the interpeduncular cistern located between the cerebral peduncles. Cerebral spinal fluid can also be obtained by puncture of the cisterna magna (cistern puncture).
Cysts of Giardia are present in the feces of infected persons. Thus, the infection is spread from person to person by contamination of food with feces, or by direct fecal-oral contamination.Cysts also survive in water, for example in fresh water lakes and streams.iardia lamblia exists in two forms, an active form called a trophozoite, and an inactive form called a cyst. The active trophozoite attaches to the lining of the small intestine with a sucker and is responsible for causing the signs and symptoms of giardiasis.