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).
Getting Properly Diagnosed. Mega Cisterna Magna and Arachnoid cysts look similar on MRI read outs so in order to correctly diagnosis a ventriculogram should be performed with the injection of dye into the blood or with a catheter into the heart.ith Mega cisterna magna the area has become enlarged but communication between the cerebellar vermis and fourth ventricle is intact. There may be no symptoms with mega cisterna magna and there will be no mass effect. This can be treated with cisternotomy.